postgresql/src/backend/parser/parse_utilcmd.c

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/*-------------------------------------------------------------------------
*
* parse_utilcmd.c
* Perform parse analysis work for various utility commands
*
* Formerly we did this work during parse_analyze_*() in analyze.c. However
* that is fairly unsafe in the presence of querytree caching, since any
* database state that we depend on in making the transformations might be
* obsolete by the time the utility command is executed; and utility commands
* have no infrastructure for holding locks or rechecking plan validity.
* Hence these functions are now called at the start of execution of their
* respective utility commands.
*
*
* Portions Copyright (c) 1996-2023, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
2010-09-20 22:08:53 +02:00
* src/backend/parser/parse_utilcmd.c
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include "access/amapi.h"
#include "access/htup_details.h"
#include "access/relation.h"
#include "access/reloptions.h"
#include "access/table.h"
Allow configurable LZ4 TOAST compression. There is now a per-column COMPRESSION option which can be set to pglz (the default, and the only option in up until now) or lz4. Or, if you like, you can set the new default_toast_compression GUC to lz4, and then that will be the default for new table columns for which no value is specified. We don't have lz4 support in the PostgreSQL code, so to use lz4 compression, PostgreSQL must be built --with-lz4. In general, TOAST compression means compression of individual column values, not the whole tuple, and those values can either be compressed inline within the tuple or compressed and then stored externally in the TOAST table, so those properties also apply to this feature. Prior to this commit, a TOAST pointer has two unused bits as part of the va_extsize field, and a compessed datum has two unused bits as part of the va_rawsize field. These bits are unused because the length of a varlena is limited to 1GB; we now use them to indicate the compression type that was used. This means we only have bit space for 2 more built-in compresison types, but we could work around that problem, if necessary, by introducing a new vartag_external value for any further types we end up wanting to add. Hopefully, it won't be too important to offer a wide selection of algorithms here, since each one we add not only takes more coding but also adds a build dependency for every packager. Nevertheless, it seems worth doing at least this much, because LZ4 gets better compression than PGLZ with less CPU usage. It's possible for LZ4-compressed datums to leak into composite type values stored on disk, just as it is for PGLZ. It's also possible for LZ4-compressed attributes to be copied into a different table via SQL commands such as CREATE TABLE AS or INSERT .. SELECT. It would be expensive to force such values to be decompressed, so PostgreSQL has never done so. For the same reasons, we also don't force recompression of already-compressed values even if the target table prefers a different compression method than was used for the source data. These architectural decisions are perhaps arguable but revisiting them is well beyond the scope of what seemed possible to do as part of this project. However, it's relatively cheap to recompress as part of VACUUM FULL or CLUSTER, so this commit adjusts those commands to do so, if the configured compression method of the table happens not to match what was used for some column value stored therein. Dilip Kumar. The original patches on which this work was based were written by Ildus Kurbangaliev, and those were patches were based on even earlier work by Nikita Glukhov, but the design has since changed very substantially, since allow a potentially large number of compression methods that could be added and dropped on a running system proved too problematic given some of the architectural issues mentioned above; the choice of which specific compression method to add first is now different; and a lot of the code has been heavily refactored. More recently, Justin Przyby helped quite a bit with testing and reviewing and this version also includes some code contributions from him. Other design input and review from Tomas Vondra, Álvaro Herrera, Andres Freund, Oleg Bartunov, Alexander Korotkov, and me. Discussion: http://postgr.es/m/20170907194236.4cefce96%40wp.localdomain Discussion: http://postgr.es/m/CAFiTN-uUpX3ck%3DK0mLEk-G_kUQY%3DSNOTeqdaNRR9FMdQrHKebw%40mail.gmail.com
2021-03-19 20:10:38 +01:00
#include "access/toast_compression.h"
#include "catalog/dependency.h"
#include "catalog/heap.h"
#include "catalog/index.h"
#include "catalog/namespace.h"
#include "catalog/pg_am.h"
#include "catalog/pg_collation.h"
#include "catalog/pg_constraint.h"
#include "catalog/pg_opclass.h"
#include "catalog/pg_operator.h"
#include "catalog/pg_statistic_ext.h"
#include "catalog/pg_type.h"
#include "commands/comment.h"
#include "commands/defrem.h"
#include "commands/sequence.h"
#include "commands/tablecmds.h"
#include "commands/tablespace.h"
#include "miscadmin.h"
#include "nodes/makefuncs.h"
#include "nodes/nodeFuncs.h"
#include "optimizer/optimizer.h"
#include "parser/analyze.h"
#include "parser/parse_clause.h"
Implement table partitioning. Table partitioning is like table inheritance and reuses much of the existing infrastructure, but there are some important differences. The parent is called a partitioned table and is always empty; it may not have indexes or non-inherited constraints, since those make no sense for a relation with no data of its own. The children are called partitions and contain all of the actual data. Each partition has an implicit partitioning constraint. Multiple inheritance is not allowed, and partitioning and inheritance can't be mixed. Partitions can't have extra columns and may not allow nulls unless the parent does. Tuples inserted into the parent are automatically routed to the correct partition, so tuple-routing ON INSERT triggers are not needed. Tuple routing isn't yet supported for partitions which are foreign tables, and it doesn't handle updates that cross partition boundaries. Currently, tables can be range-partitioned or list-partitioned. List partitioning is limited to a single column, but range partitioning can involve multiple columns. A partitioning "column" can be an expression. Because table partitioning is less general than table inheritance, it is hoped that it will be easier to reason about properties of partitions, and therefore that this will serve as a better foundation for a variety of possible optimizations, including query planner optimizations. The tuple routing based which this patch does based on the implicit partitioning constraints is an example of this, but it seems likely that many other useful optimizations are also possible. Amit Langote, reviewed and tested by Robert Haas, Ashutosh Bapat, Amit Kapila, Rajkumar Raghuwanshi, Corey Huinker, Jaime Casanova, Rushabh Lathia, Erik Rijkers, among others. Minor revisions by me.
2016-12-07 19:17:43 +01:00
#include "parser/parse_coerce.h"
#include "parser/parse_collate.h"
#include "parser/parse_expr.h"
#include "parser/parse_relation.h"
#include "parser/parse_target.h"
#include "parser/parse_type.h"
#include "parser/parse_utilcmd.h"
#include "parser/parser.h"
#include "rewrite/rewriteManip.h"
#include "utils/acl.h"
#include "utils/builtins.h"
#include "utils/lsyscache.h"
#include "utils/partcache.h"
#include "utils/rel.h"
Implement table partitioning. Table partitioning is like table inheritance and reuses much of the existing infrastructure, but there are some important differences. The parent is called a partitioned table and is always empty; it may not have indexes or non-inherited constraints, since those make no sense for a relation with no data of its own. The children are called partitions and contain all of the actual data. Each partition has an implicit partitioning constraint. Multiple inheritance is not allowed, and partitioning and inheritance can't be mixed. Partitions can't have extra columns and may not allow nulls unless the parent does. Tuples inserted into the parent are automatically routed to the correct partition, so tuple-routing ON INSERT triggers are not needed. Tuple routing isn't yet supported for partitions which are foreign tables, and it doesn't handle updates that cross partition boundaries. Currently, tables can be range-partitioned or list-partitioned. List partitioning is limited to a single column, but range partitioning can involve multiple columns. A partitioning "column" can be an expression. Because table partitioning is less general than table inheritance, it is hoped that it will be easier to reason about properties of partitions, and therefore that this will serve as a better foundation for a variety of possible optimizations, including query planner optimizations. The tuple routing based which this patch does based on the implicit partitioning constraints is an example of this, but it seems likely that many other useful optimizations are also possible. Amit Langote, reviewed and tested by Robert Haas, Ashutosh Bapat, Amit Kapila, Rajkumar Raghuwanshi, Corey Huinker, Jaime Casanova, Rushabh Lathia, Erik Rijkers, among others. Minor revisions by me.
2016-12-07 19:17:43 +01:00
#include "utils/ruleutils.h"
#include "utils/syscache.h"
#include "utils/typcache.h"
/* State shared by transformCreateStmt and its subroutines */
typedef struct
{
ParseState *pstate; /* overall parser state */
const char *stmtType; /* "CREATE [FOREIGN] TABLE" or "ALTER TABLE" */
RangeVar *relation; /* relation to create */
Relation rel; /* opened/locked rel, if ALTER */
List *inhRelations; /* relations to inherit from */
bool isforeign; /* true if CREATE/ALTER FOREIGN TABLE */
bool isalter; /* true if altering existing table */
List *columns; /* ColumnDef items */
List *ckconstraints; /* CHECK constraints */
List *fkconstraints; /* FOREIGN KEY constraints */
List *ixconstraints; /* index-creating constraints */
List *likeclauses; /* LIKE clauses that need post-processing */
List *extstats; /* cloned extended statistics */
List *blist; /* "before list" of things to do before
* creating the table */
List *alist; /* "after list" of things to do after creating
* the table */
IndexStmt *pkey; /* PRIMARY KEY index, if any */
Implement table partitioning. Table partitioning is like table inheritance and reuses much of the existing infrastructure, but there are some important differences. The parent is called a partitioned table and is always empty; it may not have indexes or non-inherited constraints, since those make no sense for a relation with no data of its own. The children are called partitions and contain all of the actual data. Each partition has an implicit partitioning constraint. Multiple inheritance is not allowed, and partitioning and inheritance can't be mixed. Partitions can't have extra columns and may not allow nulls unless the parent does. Tuples inserted into the parent are automatically routed to the correct partition, so tuple-routing ON INSERT triggers are not needed. Tuple routing isn't yet supported for partitions which are foreign tables, and it doesn't handle updates that cross partition boundaries. Currently, tables can be range-partitioned or list-partitioned. List partitioning is limited to a single column, but range partitioning can involve multiple columns. A partitioning "column" can be an expression. Because table partitioning is less general than table inheritance, it is hoped that it will be easier to reason about properties of partitions, and therefore that this will serve as a better foundation for a variety of possible optimizations, including query planner optimizations. The tuple routing based which this patch does based on the implicit partitioning constraints is an example of this, but it seems likely that many other useful optimizations are also possible. Amit Langote, reviewed and tested by Robert Haas, Ashutosh Bapat, Amit Kapila, Rajkumar Raghuwanshi, Corey Huinker, Jaime Casanova, Rushabh Lathia, Erik Rijkers, among others. Minor revisions by me.
2016-12-07 19:17:43 +01:00
bool ispartitioned; /* true if table is partitioned */
Code review focused on new node types added by partitioning support. Fix failure to check that we got a plain Const from const-simplification of a coercion request. This is the cause of bug #14666 from Tian Bing: there is an int4 to money cast, but it's only stable not immutable (because of dependence on lc_monetary), resulting in a FuncExpr that the code was miserably unequipped to deal with, or indeed even to notice that it was failing to deal with. Add test cases around this coercion behavior. In view of the above, sprinkle the code liberally with castNode() macros, in hope of catching the next such bug a bit sooner. Also, change some functions that were randomly declared to take Node* to take more specific pointer types. And change some struct fields that were declared Node* but could be given more specific types, allowing removal of assorted explicit casts. Place PARTITION_MAX_KEYS check a bit closer to the code it's protecting. Likewise check only-one-key-for-list-partitioning restriction in a less random place. Avoid not-per-project-style usages like !strcmp(...). Fix assorted failures to avoid scribbling on the input of parse transformation. I'm not sure how necessary this is, but it's entirely silly for these functions to be expending cycles to avoid that and not getting it right. Add guards against partitioning on system columns. Put backend/nodes/ support code into an order that matches handling of these node types elsewhere. Annotate the fact that somebody added location fields to PartitionBoundSpec and PartitionRangeDatum but forgot to handle them in outfuncs.c/readfuncs.c. This is fairly harmless for production purposes (since readfuncs.c would just substitute -1 anyway) but it's still bogus. It's not worth forcing a post-beta1 initdb just to fix this, but if we have another reason to force initdb before 10.0, we should go back and clean this up. Contrariwise, somebody added location fields to PartitionElem and PartitionSpec but forgot to teach exprLocation() about them. Consolidate duplicative code in transformPartitionBound(). Improve a couple of error messages. Improve assorted commentary. Re-pgindent the files touched by this patch; this affects a few comment blocks that must have been added quite recently. Report: https://postgr.es/m/20170524024550.29935.14396@wrigleys.postgresql.org
2017-05-29 05:20:28 +02:00
PartitionBoundSpec *partbound; /* transformed FOR VALUES */
bool ofType; /* true if statement contains OF typename */
} CreateStmtContext;
Fix crashes with CREATE SCHEMA AUTHORIZATION and schema elements CREATE SCHEMA AUTHORIZATION with appended schema elements can lead to crashes when comparing the schema name of the query with the schemas used in the qualification of some clauses in the elements' queries. The origin of the problem is that the transformation routine for the elements listed in a CREATE SCHEMA query uses as new, expected, schema name the one listed in CreateSchemaStmt itself. However, depending on the query, CreateSchemaStmt.schemaname may be NULL, being computed instead from the role specification of the query given by the AUTHORIZATION clause, that could be either: - A user name string, with the new schema name being set to the same value as the role given. - Guessed from CURRENT_ROLE, SESSION_ROLE or CURRENT_ROLE, with a new schema name computed from the security context where CREATE SCHEMA is running. Regression tests are added for CREATE SCHEMA with some appended elements (some of them with schema qualifications), covering also some role specification patterns. While on it, this simplifies the context structure used during the transformation of the elements listed in a CREATE SCHEMA query by removing the fields for the role specification and the role type. They were not used, and for the role specification this could be confusing as the schema name may by extracted from that at the beginning of CreateSchemaCommand(). This issue exists for a long time, so backpatch down to all the versions supported. Reported-by: Song Hongyu Author: Michael Paquier Reviewed-by: Richard Guo Discussion: https://postgr.es/m/17909-f65c12dfc5f0451d@postgresql.org Backpatch-through: 11
2023-04-28 12:29:12 +02:00
/* State shared by transformCreateSchemaStmtElements and its subroutines */
typedef struct
{
Fix crashes with CREATE SCHEMA AUTHORIZATION and schema elements CREATE SCHEMA AUTHORIZATION with appended schema elements can lead to crashes when comparing the schema name of the query with the schemas used in the qualification of some clauses in the elements' queries. The origin of the problem is that the transformation routine for the elements listed in a CREATE SCHEMA query uses as new, expected, schema name the one listed in CreateSchemaStmt itself. However, depending on the query, CreateSchemaStmt.schemaname may be NULL, being computed instead from the role specification of the query given by the AUTHORIZATION clause, that could be either: - A user name string, with the new schema name being set to the same value as the role given. - Guessed from CURRENT_ROLE, SESSION_ROLE or CURRENT_ROLE, with a new schema name computed from the security context where CREATE SCHEMA is running. Regression tests are added for CREATE SCHEMA with some appended elements (some of them with schema qualifications), covering also some role specification patterns. While on it, this simplifies the context structure used during the transformation of the elements listed in a CREATE SCHEMA query by removing the fields for the role specification and the role type. They were not used, and for the role specification this could be confusing as the schema name may by extracted from that at the beginning of CreateSchemaCommand(). This issue exists for a long time, so backpatch down to all the versions supported. Reported-by: Song Hongyu Author: Michael Paquier Reviewed-by: Richard Guo Discussion: https://postgr.es/m/17909-f65c12dfc5f0451d@postgresql.org Backpatch-through: 11
2023-04-28 12:29:12 +02:00
const char *schemaname; /* name of schema */
List *sequences; /* CREATE SEQUENCE items */
List *tables; /* CREATE TABLE items */
List *views; /* CREATE VIEW items */
List *indexes; /* CREATE INDEX items */
List *triggers; /* CREATE TRIGGER items */
List *grants; /* GRANT items */
} CreateSchemaStmtContext;
static void transformColumnDefinition(CreateStmtContext *cxt,
ColumnDef *column);
static void transformTableConstraint(CreateStmtContext *cxt,
Constraint *constraint);
static void transformTableLikeClause(CreateStmtContext *cxt,
TableLikeClause *table_like_clause);
static void transformOfType(CreateStmtContext *cxt,
TypeName *ofTypename);
static CreateStatsStmt *generateClonedExtStatsStmt(RangeVar *heapRel,
Oid heapRelid, Oid source_statsid);
static List *get_collation(Oid collation, Oid actual_datatype);
static List *get_opclass(Oid opclass, Oid actual_datatype);
static void transformIndexConstraints(CreateStmtContext *cxt);
static IndexStmt *transformIndexConstraint(Constraint *constraint,
CreateStmtContext *cxt);
static void transformExtendedStatistics(CreateStmtContext *cxt);
static void transformFKConstraints(CreateStmtContext *cxt,
bool skipValidation,
bool isAddConstraint);
static void transformCheckConstraints(CreateStmtContext *cxt,
bool skipValidation);
static void transformConstraintAttrs(CreateStmtContext *cxt,
List *constraintList);
static void transformColumnType(CreateStmtContext *cxt, ColumnDef *column);
Fix crashes with CREATE SCHEMA AUTHORIZATION and schema elements CREATE SCHEMA AUTHORIZATION with appended schema elements can lead to crashes when comparing the schema name of the query with the schemas used in the qualification of some clauses in the elements' queries. The origin of the problem is that the transformation routine for the elements listed in a CREATE SCHEMA query uses as new, expected, schema name the one listed in CreateSchemaStmt itself. However, depending on the query, CreateSchemaStmt.schemaname may be NULL, being computed instead from the role specification of the query given by the AUTHORIZATION clause, that could be either: - A user name string, with the new schema name being set to the same value as the role given. - Guessed from CURRENT_ROLE, SESSION_ROLE or CURRENT_ROLE, with a new schema name computed from the security context where CREATE SCHEMA is running. Regression tests are added for CREATE SCHEMA with some appended elements (some of them with schema qualifications), covering also some role specification patterns. While on it, this simplifies the context structure used during the transformation of the elements listed in a CREATE SCHEMA query by removing the fields for the role specification and the role type. They were not used, and for the role specification this could be confusing as the schema name may by extracted from that at the beginning of CreateSchemaCommand(). This issue exists for a long time, so backpatch down to all the versions supported. Reported-by: Song Hongyu Author: Michael Paquier Reviewed-by: Richard Guo Discussion: https://postgr.es/m/17909-f65c12dfc5f0451d@postgresql.org Backpatch-through: 11
2023-04-28 12:29:12 +02:00
static void setSchemaName(const char *context_schema, char **stmt_schema_name);
static void transformPartitionCmd(CreateStmtContext *cxt, PartitionCmd *cmd);
static List *transformPartitionRangeBounds(ParseState *pstate, List *blist,
Relation parent);
static void validateInfiniteBounds(ParseState *pstate, List *blist);
static Const *transformPartitionBoundValue(ParseState *pstate, Node *val,
const char *colName, Oid colType, int32 colTypmod,
Oid partCollation);
/*
* transformCreateStmt -
* parse analysis for CREATE TABLE
*
* Returns a List of utility commands to be done in sequence. One of these
* will be the transformed CreateStmt, but there may be additional actions
* to be done before and after the actual DefineRelation() call.
* In addition to normal utility commands such as AlterTableStmt and
* IndexStmt, the result list may contain TableLikeClause(s), representing
* the need to perform additional parse analysis after DefineRelation().
*
* SQL allows constraints to be scattered all over, so thumb through
* the columns and collect all constraints into one place.
* If there are any implied indices (e.g. UNIQUE or PRIMARY KEY)
* then expand those into multiple IndexStmt blocks.
* - thomas 1997-12-02
*/
List *
transformCreateStmt(CreateStmt *stmt, const char *queryString)
{
ParseState *pstate;
CreateStmtContext cxt;
List *result;
List *save_alist;
ListCell *elements;
Oid namespaceid;
Oid existing_relid;
ParseCallbackState pcbstate;
/* Set up pstate */
pstate = make_parsestate(NULL);
pstate->p_sourcetext = queryString;
/*
* Look up the creation namespace. This also checks permissions on the
* target namespace, locks it against concurrent drops, checks for a
* preexisting relation in that namespace with the same name, and updates
2015-02-03 08:48:45 +01:00
* stmt->relation->relpersistence if the selected namespace is temporary.
*/
setup_parser_errposition_callback(&pcbstate, pstate,
stmt->relation->location);
namespaceid =
RangeVarGetAndCheckCreationNamespace(stmt->relation, NoLock,
&existing_relid);
cancel_parser_errposition_callback(&pcbstate);
/*
* If the relation already exists and the user specified "IF NOT EXISTS",
* bail out with a NOTICE.
*/
if (stmt->if_not_exists && OidIsValid(existing_relid))
{
/*
* If we are in an extension script, insist that the pre-existing
* object be a member of the extension, to avoid security risks.
*/
ObjectAddress address;
ObjectAddressSet(address, RelationRelationId, existing_relid);
checkMembershipInCurrentExtension(&address);
/* OK to skip */
ereport(NOTICE,
(errcode(ERRCODE_DUPLICATE_TABLE),
errmsg("relation \"%s\" already exists, skipping",
stmt->relation->relname)));
return NIL;
}
Fix a couple of misbehaviors rooted in the fact that the default creation namespace isn't necessarily first in the search path (there could be implicit schemas ahead of it). Examples are test=# set search_path TO s1; test=# create view pg_timezone_names as select * from pg_timezone_names(); ERROR: "pg_timezone_names" is already a view test=# create table pg_class (f1 int primary key); ERROR: permission denied: "pg_class" is a system catalog You'd expect these commands to create the requested objects in s1, since names beginning with pg_ aren't supposed to be reserved anymore. What is happening is that we create the requested base table and then execute additional commands (here, CREATE RULE or CREATE INDEX), and that code is passed the same RangeVar that was in the original command. Since that RangeVar has schemaname = NULL, the secondary commands think they should do a path search, and that means they find system catalogs that are implicitly in front of s1 in the search path. This is perilously close to being a security hole: if the secondary command failed to apply a permission check then it'd be possible for unprivileged users to make schema modifications to system catalogs. But as far as I can find, there is no code path in which a check doesn't occur. Which makes it just a weird corner-case bug for people who are silly enough to want to name their tables the same as a system catalog. The relevant code has changed quite a bit since 8.2, which means this patch wouldn't work as-is in the back branches. Since it's a corner case no one has reported from the field, I'm not going to bother trying to back-patch.
2007-08-27 05:36:08 +02:00
/*
* If the target relation name isn't schema-qualified, make it so. This
* prevents some corner cases in which added-on rewritten commands might
* think they should apply to other relations that have the same name and
* are earlier in the search path. But a local temp table is effectively
* specified to be in pg_temp, so no need for anything extra in that case.
Fix a couple of misbehaviors rooted in the fact that the default creation namespace isn't necessarily first in the search path (there could be implicit schemas ahead of it). Examples are test=# set search_path TO s1; test=# create view pg_timezone_names as select * from pg_timezone_names(); ERROR: "pg_timezone_names" is already a view test=# create table pg_class (f1 int primary key); ERROR: permission denied: "pg_class" is a system catalog You'd expect these commands to create the requested objects in s1, since names beginning with pg_ aren't supposed to be reserved anymore. What is happening is that we create the requested base table and then execute additional commands (here, CREATE RULE or CREATE INDEX), and that code is passed the same RangeVar that was in the original command. Since that RangeVar has schemaname = NULL, the secondary commands think they should do a path search, and that means they find system catalogs that are implicitly in front of s1 in the search path. This is perilously close to being a security hole: if the secondary command failed to apply a permission check then it'd be possible for unprivileged users to make schema modifications to system catalogs. But as far as I can find, there is no code path in which a check doesn't occur. Which makes it just a weird corner-case bug for people who are silly enough to want to name their tables the same as a system catalog. The relevant code has changed quite a bit since 8.2, which means this patch wouldn't work as-is in the back branches. Since it's a corner case no one has reported from the field, I'm not going to bother trying to back-patch.
2007-08-27 05:36:08 +02:00
*/
if (stmt->relation->schemaname == NULL
&& stmt->relation->relpersistence != RELPERSISTENCE_TEMP)
Fix a couple of misbehaviors rooted in the fact that the default creation namespace isn't necessarily first in the search path (there could be implicit schemas ahead of it). Examples are test=# set search_path TO s1; test=# create view pg_timezone_names as select * from pg_timezone_names(); ERROR: "pg_timezone_names" is already a view test=# create table pg_class (f1 int primary key); ERROR: permission denied: "pg_class" is a system catalog You'd expect these commands to create the requested objects in s1, since names beginning with pg_ aren't supposed to be reserved anymore. What is happening is that we create the requested base table and then execute additional commands (here, CREATE RULE or CREATE INDEX), and that code is passed the same RangeVar that was in the original command. Since that RangeVar has schemaname = NULL, the secondary commands think they should do a path search, and that means they find system catalogs that are implicitly in front of s1 in the search path. This is perilously close to being a security hole: if the secondary command failed to apply a permission check then it'd be possible for unprivileged users to make schema modifications to system catalogs. But as far as I can find, there is no code path in which a check doesn't occur. Which makes it just a weird corner-case bug for people who are silly enough to want to name their tables the same as a system catalog. The relevant code has changed quite a bit since 8.2, which means this patch wouldn't work as-is in the back branches. Since it's a corner case no one has reported from the field, I'm not going to bother trying to back-patch.
2007-08-27 05:36:08 +02:00
stmt->relation->schemaname = get_namespace_name(namespaceid);
/* Set up CreateStmtContext */
cxt.pstate = pstate;
if (IsA(stmt, CreateForeignTableStmt))
{
cxt.stmtType = "CREATE FOREIGN TABLE";
cxt.isforeign = true;
}
else
{
cxt.stmtType = "CREATE TABLE";
cxt.isforeign = false;
}
cxt.relation = stmt->relation;
cxt.rel = NULL;
cxt.inhRelations = stmt->inhRelations;
cxt.isalter = false;
cxt.columns = NIL;
cxt.ckconstraints = NIL;
cxt.fkconstraints = NIL;
cxt.ixconstraints = NIL;
cxt.likeclauses = NIL;
cxt.extstats = NIL;
cxt.blist = NIL;
cxt.alist = NIL;
cxt.pkey = NULL;
Implement table partitioning. Table partitioning is like table inheritance and reuses much of the existing infrastructure, but there are some important differences. The parent is called a partitioned table and is always empty; it may not have indexes or non-inherited constraints, since those make no sense for a relation with no data of its own. The children are called partitions and contain all of the actual data. Each partition has an implicit partitioning constraint. Multiple inheritance is not allowed, and partitioning and inheritance can't be mixed. Partitions can't have extra columns and may not allow nulls unless the parent does. Tuples inserted into the parent are automatically routed to the correct partition, so tuple-routing ON INSERT triggers are not needed. Tuple routing isn't yet supported for partitions which are foreign tables, and it doesn't handle updates that cross partition boundaries. Currently, tables can be range-partitioned or list-partitioned. List partitioning is limited to a single column, but range partitioning can involve multiple columns. A partitioning "column" can be an expression. Because table partitioning is less general than table inheritance, it is hoped that it will be easier to reason about properties of partitions, and therefore that this will serve as a better foundation for a variety of possible optimizations, including query planner optimizations. The tuple routing based which this patch does based on the implicit partitioning constraints is an example of this, but it seems likely that many other useful optimizations are also possible. Amit Langote, reviewed and tested by Robert Haas, Ashutosh Bapat, Amit Kapila, Rajkumar Raghuwanshi, Corey Huinker, Jaime Casanova, Rushabh Lathia, Erik Rijkers, among others. Minor revisions by me.
2016-12-07 19:17:43 +01:00
cxt.ispartitioned = stmt->partspec != NULL;
cxt.partbound = stmt->partbound;
cxt.ofType = (stmt->ofTypename != NULL);
Assert(!stmt->ofTypename || !stmt->inhRelations); /* grammar enforces */
if (stmt->ofTypename)
transformOfType(&cxt, stmt->ofTypename);
Implement table partitioning. Table partitioning is like table inheritance and reuses much of the existing infrastructure, but there are some important differences. The parent is called a partitioned table and is always empty; it may not have indexes or non-inherited constraints, since those make no sense for a relation with no data of its own. The children are called partitions and contain all of the actual data. Each partition has an implicit partitioning constraint. Multiple inheritance is not allowed, and partitioning and inheritance can't be mixed. Partitions can't have extra columns and may not allow nulls unless the parent does. Tuples inserted into the parent are automatically routed to the correct partition, so tuple-routing ON INSERT triggers are not needed. Tuple routing isn't yet supported for partitions which are foreign tables, and it doesn't handle updates that cross partition boundaries. Currently, tables can be range-partitioned or list-partitioned. List partitioning is limited to a single column, but range partitioning can involve multiple columns. A partitioning "column" can be an expression. Because table partitioning is less general than table inheritance, it is hoped that it will be easier to reason about properties of partitions, and therefore that this will serve as a better foundation for a variety of possible optimizations, including query planner optimizations. The tuple routing based which this patch does based on the implicit partitioning constraints is an example of this, but it seems likely that many other useful optimizations are also possible. Amit Langote, reviewed and tested by Robert Haas, Ashutosh Bapat, Amit Kapila, Rajkumar Raghuwanshi, Corey Huinker, Jaime Casanova, Rushabh Lathia, Erik Rijkers, among others. Minor revisions by me.
2016-12-07 19:17:43 +01:00
if (stmt->partspec)
{
if (stmt->inhRelations && !stmt->partbound)
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("cannot create partitioned table as inheritance child")));
}
/*
* Run through each primary element in the table creation clause. Separate
* column defs from constraints, and do preliminary analysis.
*/
foreach(elements, stmt->tableElts)
{
Node *element = lfirst(elements);
switch (nodeTag(element))
{
case T_ColumnDef:
transformColumnDefinition(&cxt, (ColumnDef *) element);
break;
case T_Constraint:
transformTableConstraint(&cxt, (Constraint *) element);
break;
case T_TableLikeClause:
transformTableLikeClause(&cxt, (TableLikeClause *) element);
break;
default:
elog(ERROR, "unrecognized node type: %d",
(int) nodeTag(element));
break;
}
}
/*
Avoid order-of-execution problems with ALTER TABLE ADD PRIMARY KEY. Up to now, DefineIndex() was responsible for adding attnotnull constraints to the columns of a primary key, in any case where it hadn't been convenient for transformIndexConstraint() to mark those columns as is_not_null. It (or rather its minion index_check_primary_key) did this by executing an ALTER TABLE SET NOT NULL command for the target table. The trouble with this solution is that if we're creating the index due to ALTER TABLE ADD PRIMARY KEY, and the outer ALTER TABLE has additional sub-commands, the inner ALTER TABLE's operations executed at the wrong time with respect to the outer ALTER TABLE's operations. In particular, the inner ALTER would perform a validation scan at a point where the table's storage might be inconsistent with its catalog entries. (This is on the hairy edge of being a security problem, but AFAICS it isn't one because the inner scan would only be interested in the tuples' null bitmaps.) This can result in unexpected failures, such as the one seen in bug #15580 from Allison Kaptur. To fix, let's remove the attempt to do SET NOT NULL from DefineIndex(), reducing index_check_primary_key's role to verifying that the columns are already not null. (It shouldn't ever see such a case, but it seems wise to keep the check for safety.) Instead, make transformIndexConstraint() generate ALTER TABLE SET NOT NULL subcommands to be executed ahead of the ADD PRIMARY KEY operation in every case where it can't force the column to be created already-not-null. This requires only minor surgery in parse_utilcmd.c, and it makes for a much more satisfying spec for transformIndexConstraint(): it's no longer having to take it on faith that someone else will handle addition of NOT NULL constraints. To make that work, we have to move the execution of AT_SetNotNull into an ALTER pass that executes ahead of AT_PASS_ADD_INDEX. I moved it to AT_PASS_COL_ATTRS, and put that after AT_PASS_ADD_COL to avoid failure when the column is being added in the same command. This incidentally fixes a bug in the only previous usage of AT_PASS_COL_ATTRS, for AT_SetIdentity: it didn't work either for a newly-added column. Playing around with this exposed a separate bug in ALTER TABLE ONLY ... ADD PRIMARY KEY for partitioned tables. The intent of the ONLY modifier in that context is to prevent doing anything that would require holding lock for a long time --- but the implied SET NOT NULL would recurse to the child partitions, and do an expensive validation scan for any child where the column(s) were not already NOT NULL. To fix that, invent a new ALTER subcommand AT_CheckNotNull that just insists that a child column be already NOT NULL, and apply that, not AT_SetNotNull, when recursing to children in this scenario. This results in a slightly laxer definition of ALTER TABLE ONLY ... SET NOT NULL for partitioned tables, too: that command will now work as long as all children are already NOT NULL, whereas before it just threw up its hands if there were any partitions. In passing, clean up the API of generateClonedIndexStmt(): remove a useless argument, ensure that the output argument is not left undefined, update the header comment. A small side effect of this change is that no-such-column errors in ALTER TABLE ADD PRIMARY KEY now produce a different message that includes the table name, because they are now detected by the SET NOT NULL step which has historically worded its error that way. That seems fine to me, so I didn't make any effort to avoid the wording change. The basic bug #15580 is of very long standing, and these other bugs aren't new in v12 either. However, this is a pretty significant change in the way ALTER TABLE ADD PRIMARY KEY works. On balance it seems best not to back-patch, at least not till we get some more confidence that this patch has no new bugs. Patch by me, but thanks to Jie Zhang for a preliminary version. Discussion: https://postgr.es/m/15580-d1a6de5a3d65da51@postgresql.org Discussion: https://postgr.es/m/1396E95157071C4EBBA51892C5368521017F2E6E63@G08CNEXMBPEKD02.g08.fujitsu.local
2019-04-23 18:25:27 +02:00
* Transfer anything we already have in cxt.alist into save_alist, to keep
* it separate from the output of transformIndexConstraints. (This may
* not be necessary anymore, but we'll keep doing it to preserve the
* historical order of execution of the alist commands.)
*/
save_alist = cxt.alist;
cxt.alist = NIL;
Assert(stmt->constraints == NIL);
/*
* Postprocess constraints that give rise to index definitions.
*/
transformIndexConstraints(&cxt);
/*
* Re-consideration of LIKE clauses should happen after creation of
* indexes, but before creation of foreign keys. This order is critical
* because a LIKE clause may attempt to create a primary key. If there's
* also a pkey in the main CREATE TABLE list, creation of that will not
* check for a duplicate at runtime (since index_check_primary_key()
* expects that we rejected dups here). Creation of the LIKE-generated
* pkey behaves like ALTER TABLE ADD, so it will check, but obviously that
* only works if it happens second. On the other hand, we want to make
* pkeys before foreign key constraints, in case the user tries to make a
* self-referential FK.
*/
cxt.alist = list_concat(cxt.alist, cxt.likeclauses);
/*
* Postprocess foreign-key constraints.
*/
transformFKConstraints(&cxt, true, false);
/*
* Postprocess check constraints.
*
* For regular tables all constraints can be marked valid immediately,
* because the table is new therefore empty. Not so for foreign tables.
*/
transformCheckConstraints(&cxt, !cxt.isforeign);
/*
* Postprocess extended statistics.
*/
transformExtendedStatistics(&cxt);
/*
* Output results.
*/
stmt->tableElts = cxt.columns;
stmt->constraints = cxt.ckconstraints;
result = lappend(cxt.blist, stmt);
result = list_concat(result, cxt.alist);
result = list_concat(result, save_alist);
return result;
}
/*
* generateSerialExtraStmts
* Generate CREATE SEQUENCE and ALTER SEQUENCE ... OWNED BY statements
* to create the sequence for a serial or identity column.
*
* This includes determining the name the sequence will have. The caller
* can ask to get back the name components by passing non-null pointers
* for snamespace_p and sname_p.
*/
static void
generateSerialExtraStmts(CreateStmtContext *cxt, ColumnDef *column,
Restructure ALTER TABLE execution to fix assorted bugs. We've had numerous bug reports about how (1) IF NOT EXISTS clauses in ALTER TABLE don't behave as-expected, and (2) combining certain actions into one ALTER TABLE doesn't work, though executing the same actions as separate statements does. This patch cleans up all of the cases so far reported from the field, though there are still some oddities associated with identity columns. The core problem behind all of these bugs is that we do parse analysis of ALTER TABLE subcommands too soon, before starting execution of the statement. The root of the bugs in group (1) is that parse analysis schedules derived commands (such as a CREATE SEQUENCE for a serial column) before it's known whether the IF NOT EXISTS clause should cause a subcommand to be skipped. The root of the bugs in group (2) is that earlier subcommands may change the catalog state that later subcommands need to be parsed against. Hence, postpone parse analysis of ALTER TABLE's subcommands, and do that one subcommand at a time, during "phase 2" of ALTER TABLE which is the phase that does catalog rewrites. Thus the catalog effects of earlier subcommands are already visible when we analyze later ones. (The sole exception is that we do parse analysis for ALTER COLUMN TYPE subcommands during phase 1, so that their USING expressions can be parsed against the table's original state, which is what we need. Arguably, these bugs stem from falsely concluding that because ALTER COLUMN TYPE must do early parse analysis, every other command subtype can too.) This means that ALTER TABLE itself must deal with execution of any non-ALTER-TABLE derived statements that are generated by parse analysis. Add a suitable entry point to utility.c to accept those recursive calls, and create a struct to pass through the information needed by the recursive call, rather than making the argument lists of AlterTable() and friends even longer. Getting this to work correctly required a little bit of fiddling with the subcommand pass structure, in particular breaking up AT_PASS_ADD_CONSTR into multiple passes. But otherwise it's mostly a pretty straightforward application of the above ideas. Fixing the residual issues for identity columns requires refactoring of where the dependency link from an identity column to its sequence gets set up. So that seems like suitable material for a separate patch, especially since this one is pretty big already. Discussion: https://postgr.es/m/10365.1558909428@sss.pgh.pa.us
2020-01-16 00:49:24 +01:00
Oid seqtypid, List *seqoptions,
bool for_identity, bool col_exists,
char **snamespace_p, char **sname_p)
{
ListCell *option;
DefElem *nameEl = NULL;
Oid snamespaceid;
char *snamespace;
char *sname;
CreateSeqStmt *seqstmt;
AlterSeqStmt *altseqstmt;
List *attnamelist;
int nameEl_idx = -1;
/* Make a copy of this as we may end up modifying it in the code below */
seqoptions = list_copy(seqoptions);
/*
* Determine namespace and name to use for the sequence.
*
* First, check if a sequence name was passed in as an option. This is
* used by pg_dump. Else, generate a name.
*
* Although we use ChooseRelationName, it's not guaranteed that the
* selected sequence name won't conflict; given sufficiently long field
* names, two different serial columns in the same table could be assigned
* the same sequence name, and we'd not notice since we aren't creating
* the sequence quite yet. In practice this seems quite unlikely to be a
* problem, especially since few people would need two serial columns in
* one table.
*/
foreach(option, seqoptions)
{
DefElem *defel = lfirst_node(DefElem, option);
if (strcmp(defel->defname, "sequence_name") == 0)
{
if (nameEl)
errorConflictingDefElem(defel, cxt->pstate);
nameEl = defel;
nameEl_idx = foreach_current_index(option);
}
}
if (nameEl)
{
RangeVar *rv = makeRangeVarFromNameList(castNode(List, nameEl->arg));
snamespace = rv->schemaname;
if (!snamespace)
{
/* Given unqualified SEQUENCE NAME, select namespace */
if (cxt->rel)
snamespaceid = RelationGetNamespace(cxt->rel);
else
snamespaceid = RangeVarGetCreationNamespace(cxt->relation);
snamespace = get_namespace_name(snamespaceid);
}
sname = rv->relname;
/* Remove the SEQUENCE NAME item from seqoptions */
seqoptions = list_delete_nth_cell(seqoptions, nameEl_idx);
}
else
{
if (cxt->rel)
snamespaceid = RelationGetNamespace(cxt->rel);
else
{
snamespaceid = RangeVarGetCreationNamespace(cxt->relation);
RangeVarAdjustRelationPersistence(cxt->relation, snamespaceid);
}
snamespace = get_namespace_name(snamespaceid);
sname = ChooseRelationName(cxt->relation->relname,
column->colname,
"seq",
Fully enforce uniqueness of constraint names. It's been true for a long time that we expect names of table and domain constraints to be unique among the constraints of that table or domain. However, the enforcement of that has been pretty haphazard, and it missed some corner cases such as creating a CHECK constraint and then an index constraint of the same name (as per recent report from André Hänsel). Also, due to the lack of an actual unique index enforcing this, duplicates could be created through race conditions. Moreover, the code that searches pg_constraint has been quite inconsistent about how to handle duplicate names if one did occur: some places checked and threw errors if there was more than one match, while others just processed the first match they came to. To fix, create a unique index on (conrelid, contypid, conname). Since either conrelid or contypid is zero, this will separately enforce uniqueness of constraint names among constraints of any one table and any one domain. (If we ever implement SQL assertions, and put them into this catalog, more thought might be needed. But it'd be at least as reasonable to put them into a new catalog; having overloaded this one catalog with two kinds of constraints was a mistake already IMO.) This index can replace the existing non-unique index on conrelid, though we need to keep the one on contypid for query performance reasons. Having done that, we can simplify the logic in various places that either coped with duplicates or neglected to, as well as potentially improve lookup performance when searching for a constraint by name. Also, as per our usual practice, install a preliminary check so that you get something more friendly than a unique-index violation report in the case complained of by André. And teach ChooseIndexName to avoid choosing autogenerated names that would draw such a failure. While it's not possible to make such a change in the back branches, it doesn't seem quite too late to put this into v11, so do so. Discussion: https://postgr.es/m/0c1001d4428f$0942b430$1bc81c90$@webkr.de
2018-09-04 19:45:35 +02:00
snamespaceid,
false);
}
ereport(DEBUG1,
(errmsg_internal("%s will create implicit sequence \"%s\" for serial column \"%s.%s\"",
cxt->stmtType, sname,
cxt->relation->relname, column->colname)));
/*
* Build a CREATE SEQUENCE command to create the sequence object, and add
* it to the list of things to be done before this CREATE/ALTER TABLE.
*/
seqstmt = makeNode(CreateSeqStmt);
seqstmt->for_identity = for_identity;
seqstmt->sequence = makeRangeVar(snamespace, sname, -1);
seqstmt->sequence->relpersistence = cxt->relation->relpersistence;
seqstmt->options = seqoptions;
/*
* If a sequence data type was specified, add it to the options. Prepend
* to the list rather than append; in case a user supplied their own AS
* clause, the "redundant options" error will point to their occurrence,
* not our synthetic one.
*/
if (seqtypid)
seqstmt->options = lcons(makeDefElem("as",
(Node *) makeTypeNameFromOid(seqtypid, -1),
-1),
seqstmt->options);
/*
* If this is ALTER ADD COLUMN, make sure the sequence will be owned by
* the table's owner. The current user might be someone else (perhaps a
* superuser, or someone who's only a member of the owning role), but the
* SEQUENCE OWNED BY mechanisms will bleat unless table and sequence have
* exactly the same owning role.
*/
if (cxt->rel)
seqstmt->ownerId = cxt->rel->rd_rel->relowner;
else
seqstmt->ownerId = InvalidOid;
cxt->blist = lappend(cxt->blist, seqstmt);
/*
* Store the identity sequence name that we decided on. ALTER TABLE ...
* ADD COLUMN ... IDENTITY needs this so that it can fill the new column
* with values from the sequence, while the association of the sequence
* with the table is not set until after the ALTER TABLE.
*/
column->identitySequence = seqstmt->sequence;
/*
* Build an ALTER SEQUENCE ... OWNED BY command to mark the sequence as
Restructure ALTER TABLE execution to fix assorted bugs. We've had numerous bug reports about how (1) IF NOT EXISTS clauses in ALTER TABLE don't behave as-expected, and (2) combining certain actions into one ALTER TABLE doesn't work, though executing the same actions as separate statements does. This patch cleans up all of the cases so far reported from the field, though there are still some oddities associated with identity columns. The core problem behind all of these bugs is that we do parse analysis of ALTER TABLE subcommands too soon, before starting execution of the statement. The root of the bugs in group (1) is that parse analysis schedules derived commands (such as a CREATE SEQUENCE for a serial column) before it's known whether the IF NOT EXISTS clause should cause a subcommand to be skipped. The root of the bugs in group (2) is that earlier subcommands may change the catalog state that later subcommands need to be parsed against. Hence, postpone parse analysis of ALTER TABLE's subcommands, and do that one subcommand at a time, during "phase 2" of ALTER TABLE which is the phase that does catalog rewrites. Thus the catalog effects of earlier subcommands are already visible when we analyze later ones. (The sole exception is that we do parse analysis for ALTER COLUMN TYPE subcommands during phase 1, so that their USING expressions can be parsed against the table's original state, which is what we need. Arguably, these bugs stem from falsely concluding that because ALTER COLUMN TYPE must do early parse analysis, every other command subtype can too.) This means that ALTER TABLE itself must deal with execution of any non-ALTER-TABLE derived statements that are generated by parse analysis. Add a suitable entry point to utility.c to accept those recursive calls, and create a struct to pass through the information needed by the recursive call, rather than making the argument lists of AlterTable() and friends even longer. Getting this to work correctly required a little bit of fiddling with the subcommand pass structure, in particular breaking up AT_PASS_ADD_CONSTR into multiple passes. But otherwise it's mostly a pretty straightforward application of the above ideas. Fixing the residual issues for identity columns requires refactoring of where the dependency link from an identity column to its sequence gets set up. So that seems like suitable material for a separate patch, especially since this one is pretty big already. Discussion: https://postgr.es/m/10365.1558909428@sss.pgh.pa.us
2020-01-16 00:49:24 +01:00
* owned by this column, and add it to the appropriate list of things to
* be done along with this CREATE/ALTER TABLE. In a CREATE or ALTER ADD
* COLUMN, it must be done after the statement because we don't know the
* column's attnum yet. But if we do have the attnum (in AT_AddIdentity),
* we can do the marking immediately, which improves some ALTER TABLE
* behaviors.
*/
altseqstmt = makeNode(AlterSeqStmt);
altseqstmt->sequence = makeRangeVar(snamespace, sname, -1);
attnamelist = list_make3(makeString(snamespace),
makeString(cxt->relation->relname),
makeString(column->colname));
altseqstmt->options = list_make1(makeDefElem("owned_by",
(Node *) attnamelist, -1));
altseqstmt->for_identity = for_identity;
Restructure ALTER TABLE execution to fix assorted bugs. We've had numerous bug reports about how (1) IF NOT EXISTS clauses in ALTER TABLE don't behave as-expected, and (2) combining certain actions into one ALTER TABLE doesn't work, though executing the same actions as separate statements does. This patch cleans up all of the cases so far reported from the field, though there are still some oddities associated with identity columns. The core problem behind all of these bugs is that we do parse analysis of ALTER TABLE subcommands too soon, before starting execution of the statement. The root of the bugs in group (1) is that parse analysis schedules derived commands (such as a CREATE SEQUENCE for a serial column) before it's known whether the IF NOT EXISTS clause should cause a subcommand to be skipped. The root of the bugs in group (2) is that earlier subcommands may change the catalog state that later subcommands need to be parsed against. Hence, postpone parse analysis of ALTER TABLE's subcommands, and do that one subcommand at a time, during "phase 2" of ALTER TABLE which is the phase that does catalog rewrites. Thus the catalog effects of earlier subcommands are already visible when we analyze later ones. (The sole exception is that we do parse analysis for ALTER COLUMN TYPE subcommands during phase 1, so that their USING expressions can be parsed against the table's original state, which is what we need. Arguably, these bugs stem from falsely concluding that because ALTER COLUMN TYPE must do early parse analysis, every other command subtype can too.) This means that ALTER TABLE itself must deal with execution of any non-ALTER-TABLE derived statements that are generated by parse analysis. Add a suitable entry point to utility.c to accept those recursive calls, and create a struct to pass through the information needed by the recursive call, rather than making the argument lists of AlterTable() and friends even longer. Getting this to work correctly required a little bit of fiddling with the subcommand pass structure, in particular breaking up AT_PASS_ADD_CONSTR into multiple passes. But otherwise it's mostly a pretty straightforward application of the above ideas. Fixing the residual issues for identity columns requires refactoring of where the dependency link from an identity column to its sequence gets set up. So that seems like suitable material for a separate patch, especially since this one is pretty big already. Discussion: https://postgr.es/m/10365.1558909428@sss.pgh.pa.us
2020-01-16 00:49:24 +01:00
if (col_exists)
cxt->blist = lappend(cxt->blist, altseqstmt);
else
cxt->alist = lappend(cxt->alist, altseqstmt);
if (snamespace_p)
*snamespace_p = snamespace;
if (sname_p)
*sname_p = sname;
}
/*
* transformColumnDefinition -
* transform a single ColumnDef within CREATE TABLE
* Also used in ALTER TABLE ADD COLUMN
*/
static void
transformColumnDefinition(CreateStmtContext *cxt, ColumnDef *column)
{
bool is_serial;
bool saw_nullable;
bool saw_default;
bool saw_identity;
bool saw_generated;
ListCell *clist;
cxt->columns = lappend(cxt->columns, column);
/* Check for SERIAL pseudo-types */
is_serial = false;
if (column->typeName
&& list_length(column->typeName->names) == 1
&& !column->typeName->pct_type)
{
char *typname = strVal(linitial(column->typeName->names));
if (strcmp(typname, "smallserial") == 0 ||
strcmp(typname, "serial2") == 0)
{
is_serial = true;
column->typeName->names = NIL;
column->typeName->typeOid = INT2OID;
}
else if (strcmp(typname, "serial") == 0 ||
strcmp(typname, "serial4") == 0)
{
is_serial = true;
column->typeName->names = NIL;
column->typeName->typeOid = INT4OID;
}
else if (strcmp(typname, "bigserial") == 0 ||
strcmp(typname, "serial8") == 0)
{
is_serial = true;
column->typeName->names = NIL;
column->typeName->typeOid = INT8OID;
}
/*
* We have to reject "serial[]" explicitly, because once we've set
* typeid, LookupTypeName won't notice arrayBounds. We don't need any
* special coding for serial(typmod) though.
*/
if (is_serial && column->typeName->arrayBounds != NIL)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("array of serial is not implemented"),
parser_errposition(cxt->pstate,
column->typeName->location)));
}
/* Do necessary work on the column type declaration */
if (column->typeName)
transformColumnType(cxt, column);
/* Special actions for SERIAL pseudo-types */
if (is_serial)
{
char *snamespace;
char *sname;
char *qstring;
A_Const *snamenode;
TypeCast *castnode;
FuncCall *funccallnode;
Constraint *constraint;
generateSerialExtraStmts(cxt, column,
Restructure ALTER TABLE execution to fix assorted bugs. We've had numerous bug reports about how (1) IF NOT EXISTS clauses in ALTER TABLE don't behave as-expected, and (2) combining certain actions into one ALTER TABLE doesn't work, though executing the same actions as separate statements does. This patch cleans up all of the cases so far reported from the field, though there are still some oddities associated with identity columns. The core problem behind all of these bugs is that we do parse analysis of ALTER TABLE subcommands too soon, before starting execution of the statement. The root of the bugs in group (1) is that parse analysis schedules derived commands (such as a CREATE SEQUENCE for a serial column) before it's known whether the IF NOT EXISTS clause should cause a subcommand to be skipped. The root of the bugs in group (2) is that earlier subcommands may change the catalog state that later subcommands need to be parsed against. Hence, postpone parse analysis of ALTER TABLE's subcommands, and do that one subcommand at a time, during "phase 2" of ALTER TABLE which is the phase that does catalog rewrites. Thus the catalog effects of earlier subcommands are already visible when we analyze later ones. (The sole exception is that we do parse analysis for ALTER COLUMN TYPE subcommands during phase 1, so that their USING expressions can be parsed against the table's original state, which is what we need. Arguably, these bugs stem from falsely concluding that because ALTER COLUMN TYPE must do early parse analysis, every other command subtype can too.) This means that ALTER TABLE itself must deal with execution of any non-ALTER-TABLE derived statements that are generated by parse analysis. Add a suitable entry point to utility.c to accept those recursive calls, and create a struct to pass through the information needed by the recursive call, rather than making the argument lists of AlterTable() and friends even longer. Getting this to work correctly required a little bit of fiddling with the subcommand pass structure, in particular breaking up AT_PASS_ADD_CONSTR into multiple passes. But otherwise it's mostly a pretty straightforward application of the above ideas. Fixing the residual issues for identity columns requires refactoring of where the dependency link from an identity column to its sequence gets set up. So that seems like suitable material for a separate patch, especially since this one is pretty big already. Discussion: https://postgr.es/m/10365.1558909428@sss.pgh.pa.us
2020-01-16 00:49:24 +01:00
column->typeName->typeOid, NIL,
false, false,
&snamespace, &sname);
/*
* Create appropriate constraints for SERIAL. We do this in full,
* rather than shortcutting, so that we will detect any conflicting
* constraints the user wrote (like a different DEFAULT).
*
* Create an expression tree representing the function call
* nextval('sequencename'). We cannot reduce the raw tree to cooked
* form until after the sequence is created, but there's no need to do
* so.
*/
qstring = quote_qualified_identifier(snamespace, sname);
snamenode = makeNode(A_Const);
snamenode->val.node.type = T_String;
snamenode->val.sval.sval = qstring;
snamenode->location = -1;
castnode = makeNode(TypeCast);
castnode->typeName = SystemTypeName("regclass");
castnode->arg = (Node *) snamenode;
castnode->location = -1;
funccallnode = makeFuncCall(SystemFuncName("nextval"),
list_make1(castnode),
Improve our ability to regurgitate SQL-syntax function calls. The SQL spec calls out nonstandard syntax for certain function calls, for example substring() with numeric position info is supposed to be spelled "SUBSTRING(string FROM start FOR count)". We accept many of these things, but up to now would not print them in the same format, instead simplifying down to "substring"(string, start, count). That's long annoyed me because it creates an interoperability problem: we're gratuitously injecting Postgres-specific syntax into what might otherwise be a perfectly spec-compliant view definition. However, the real reason for addressing it right now is to support a planned change in the semantics of EXTRACT() a/k/a date_part(). When we switch that to returning numeric, we'll have the parser translate EXTRACT() to some new function name (might as well be "extract" if you ask me) and then teach ruleutils.c to reverse-list that per SQL spec. In this way existing calls to date_part() will continue to have the old semantics. To implement this, invent a new CoercionForm value COERCE_SQL_SYNTAX, and make the parser insert that rather than COERCE_EXPLICIT_CALL when the input has SQL-spec decoration. (But if the input has the form of a plain function call, continue to mark it COERCE_EXPLICIT_CALL, even if it's calling one of these functions.) Then ruleutils.c recognizes COERCE_SQL_SYNTAX as a cue to emit SQL call syntax. It can know which decoration to emit using hard-wired knowledge about the functions that could be called this way. (While this solution isn't extensible without manual additions, neither is the grammar, so this doesn't seem unmaintainable.) Notice that this solution will reverse-list a function call with SQL decoration only if it was entered that way; so dump-and-reload will not by itself produce any changes in the appearance of views. This requires adding a CoercionForm field to struct FuncCall. (I couldn't resist the temptation to rearrange that struct's field order a tad while I was at it.) FuncCall doesn't appear in stored rules, so that change isn't a reason for a catversion bump, but I did one anyway because the new enum value for CoercionForm fields could confuse old backend code. Possible future work: * Perhaps CoercionForm should now be renamed to DisplayForm, or something like that, to reflect its more general meaning. This'd require touching a couple hundred places, so it's not clear it's worth the code churn. * The SQLValueFunction node type, which was invented partly for the same goal of improving SQL-compatibility of view output, could perhaps be replaced with regular function calls marked with COERCE_SQL_SYNTAX. It's unclear if this would be a net code savings, however. Discussion: https://postgr.es/m/42b73d2d-da12-ba9f-570a-420e0cce19d9@phystech.edu
2020-11-04 18:34:50 +01:00
COERCE_EXPLICIT_CALL,
-1);
constraint = makeNode(Constraint);
constraint->contype = CONSTR_DEFAULT;
constraint->location = -1;
constraint->raw_expr = (Node *) funccallnode;
constraint->cooked_expr = NULL;
column->constraints = lappend(column->constraints, constraint);
constraint = makeNode(Constraint);
constraint->contype = CONSTR_NOTNULL;
constraint->location = -1;
column->constraints = lappend(column->constraints, constraint);
}
/* Process column constraints, if any... */
transformConstraintAttrs(cxt, column->constraints);
saw_nullable = false;
saw_default = false;
saw_identity = false;
saw_generated = false;
foreach(clist, column->constraints)
{
Constraint *constraint = lfirst_node(Constraint, clist);
switch (constraint->contype)
{
case CONSTR_NULL:
if (saw_nullable && column->is_not_null)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("conflicting NULL/NOT NULL declarations for column \"%s\" of table \"%s\"",
column->colname, cxt->relation->relname),
parser_errposition(cxt->pstate,
constraint->location)));
column->is_not_null = false;
saw_nullable = true;
break;
case CONSTR_NOTNULL:
if (saw_nullable && !column->is_not_null)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("conflicting NULL/NOT NULL declarations for column \"%s\" of table \"%s\"",
column->colname, cxt->relation->relname),
parser_errposition(cxt->pstate,
constraint->location)));
column->is_not_null = true;
saw_nullable = true;
break;
case CONSTR_DEFAULT:
if (saw_default)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("multiple default values specified for column \"%s\" of table \"%s\"",
column->colname, cxt->relation->relname),
parser_errposition(cxt->pstate,
constraint->location)));
column->raw_default = constraint->raw_expr;
Assert(constraint->cooked_expr == NULL);
saw_default = true;
break;
case CONSTR_IDENTITY:
{
Type ctype;
Oid typeOid;
if (cxt->ofType)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("identity columns are not supported on typed tables")));
if (cxt->partbound)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
2017-12-09 11:40:31 +01:00
errmsg("identity columns are not supported on partitions")));
ctype = typenameType(cxt->pstate, column->typeName, NULL);
Remove WITH OIDS support, change oid catalog column visibility. Previously tables declared WITH OIDS, including a significant fraction of the catalog tables, stored the oid column not as a normal column, but as part of the tuple header. This special column was not shown by default, which was somewhat odd, as it's often (consider e.g. pg_class.oid) one of the more important parts of a row. Neither pg_dump nor COPY included the contents of the oid column by default. The fact that the oid column was not an ordinary column necessitated a significant amount of special case code to support oid columns. That already was painful for the existing, but upcoming work aiming to make table storage pluggable, would have required expanding and duplicating that "specialness" significantly. WITH OIDS has been deprecated since 2005 (commit ff02d0a05280e0). Remove it. Removing includes: - CREATE TABLE and ALTER TABLE syntax for declaring the table to be WITH OIDS has been removed (WITH (oids[ = true]) will error out) - pg_dump does not support dumping tables declared WITH OIDS and will issue a warning when dumping one (and ignore the oid column). - restoring an pg_dump archive with pg_restore will warn when restoring a table with oid contents (and ignore the oid column) - COPY will refuse to load binary dump that includes oids. - pg_upgrade will error out when encountering tables declared WITH OIDS, they have to be altered to remove the oid column first. - Functionality to access the oid of the last inserted row (like plpgsql's RESULT_OID, spi's SPI_lastoid, ...) has been removed. The syntax for declaring a table WITHOUT OIDS (or WITH (oids = false) for CREATE TABLE) is still supported. While that requires a bit of support code, it seems unnecessary to break applications / dumps that do not use oids, and are explicit about not using them. The biggest user of WITH OID columns was postgres' catalog. This commit changes all 'magic' oid columns to be columns that are normally declared and stored. To reduce unnecessary query breakage all the newly added columns are still named 'oid', even if a table's column naming scheme would indicate 'reloid' or such. This obviously requires adapting a lot code, mostly replacing oid access via HeapTupleGetOid() with access to the underlying Form_pg_*->oid column. The bootstrap process now assigns oids for all oid columns in genbki.pl that do not have an explicit value (starting at the largest oid previously used), only oids assigned later by oids will be above FirstBootstrapObjectId. As the oid column now is a normal column the special bootstrap syntax for oids has been removed. Oids are not automatically assigned during insertion anymore, all backend code explicitly assigns oids with GetNewOidWithIndex(). For the rare case that insertions into the catalog via SQL are called for the new pg_nextoid() function can be used (which only works on catalog tables). The fact that oid columns on system tables are now normal columns means that they will be included in the set of columns expanded by * (i.e. SELECT * FROM pg_class will now include the table's oid, previously it did not). It'd not technically be hard to hide oid column by default, but that'd mean confusing behavior would either have to be carried forward forever, or it'd cause breakage down the line. While it's not unlikely that further adjustments are needed, the scope/invasiveness of the patch makes it worthwhile to get merge this now. It's painful to maintain externally, too complicated to commit after the code code freeze, and a dependency of a number of other patches. Catversion bump, for obvious reasons. Author: Andres Freund, with contributions by John Naylor Discussion: https://postgr.es/m/20180930034810.ywp2c7awz7opzcfr@alap3.anarazel.de
2018-11-21 00:36:57 +01:00
typeOid = ((Form_pg_type) GETSTRUCT(ctype))->oid;
ReleaseSysCache(ctype);
if (saw_identity)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("multiple identity specifications for column \"%s\" of table \"%s\"",
column->colname, cxt->relation->relname),
parser_errposition(cxt->pstate,
constraint->location)));
generateSerialExtraStmts(cxt, column,
Restructure ALTER TABLE execution to fix assorted bugs. We've had numerous bug reports about how (1) IF NOT EXISTS clauses in ALTER TABLE don't behave as-expected, and (2) combining certain actions into one ALTER TABLE doesn't work, though executing the same actions as separate statements does. This patch cleans up all of the cases so far reported from the field, though there are still some oddities associated with identity columns. The core problem behind all of these bugs is that we do parse analysis of ALTER TABLE subcommands too soon, before starting execution of the statement. The root of the bugs in group (1) is that parse analysis schedules derived commands (such as a CREATE SEQUENCE for a serial column) before it's known whether the IF NOT EXISTS clause should cause a subcommand to be skipped. The root of the bugs in group (2) is that earlier subcommands may change the catalog state that later subcommands need to be parsed against. Hence, postpone parse analysis of ALTER TABLE's subcommands, and do that one subcommand at a time, during "phase 2" of ALTER TABLE which is the phase that does catalog rewrites. Thus the catalog effects of earlier subcommands are already visible when we analyze later ones. (The sole exception is that we do parse analysis for ALTER COLUMN TYPE subcommands during phase 1, so that their USING expressions can be parsed against the table's original state, which is what we need. Arguably, these bugs stem from falsely concluding that because ALTER COLUMN TYPE must do early parse analysis, every other command subtype can too.) This means that ALTER TABLE itself must deal with execution of any non-ALTER-TABLE derived statements that are generated by parse analysis. Add a suitable entry point to utility.c to accept those recursive calls, and create a struct to pass through the information needed by the recursive call, rather than making the argument lists of AlterTable() and friends even longer. Getting this to work correctly required a little bit of fiddling with the subcommand pass structure, in particular breaking up AT_PASS_ADD_CONSTR into multiple passes. But otherwise it's mostly a pretty straightforward application of the above ideas. Fixing the residual issues for identity columns requires refactoring of where the dependency link from an identity column to its sequence gets set up. So that seems like suitable material for a separate patch, especially since this one is pretty big already. Discussion: https://postgr.es/m/10365.1558909428@sss.pgh.pa.us
2020-01-16 00:49:24 +01:00
typeOid, constraint->options,
true, false,
NULL, NULL);
column->identity = constraint->generated_when;
saw_identity = true;
/* An identity column is implicitly NOT NULL */
if (saw_nullable && !column->is_not_null)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("conflicting NULL/NOT NULL declarations for column \"%s\" of table \"%s\"",
column->colname, cxt->relation->relname),
parser_errposition(cxt->pstate,
constraint->location)));
column->is_not_null = true;
saw_nullable = true;
break;
}
case CONSTR_GENERATED:
if (cxt->ofType)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("generated columns are not supported on typed tables")));
if (saw_generated)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("multiple generation clauses specified for column \"%s\" of table \"%s\"",
column->colname, cxt->relation->relname),
parser_errposition(cxt->pstate,
constraint->location)));
column->generated = ATTRIBUTE_GENERATED_STORED;
column->raw_default = constraint->raw_expr;
Assert(constraint->cooked_expr == NULL);
saw_generated = true;
break;
case CONSTR_CHECK:
cxt->ckconstraints = lappend(cxt->ckconstraints, constraint);
break;
case CONSTR_PRIMARY:
if (cxt->isforeign)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("primary key constraints are not supported on foreign tables"),
parser_errposition(cxt->pstate,
constraint->location)));
/* FALL THRU */
case CONSTR_UNIQUE:
if (cxt->isforeign)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("unique constraints are not supported on foreign tables"),
parser_errposition(cxt->pstate,
constraint->location)));
if (constraint->keys == NIL)
constraint->keys = list_make1(makeString(column->colname));
cxt->ixconstraints = lappend(cxt->ixconstraints, constraint);
break;
case CONSTR_EXCLUSION:
/* grammar does not allow EXCLUDE as a column constraint */
elog(ERROR, "column exclusion constraints are not supported");
break;
case CONSTR_FOREIGN:
if (cxt->isforeign)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("foreign key constraints are not supported on foreign tables"),
parser_errposition(cxt->pstate,
constraint->location)));
/*
* Fill in the current attribute's name and throw it into the
* list of FK constraints to be processed later.
*/
constraint->fk_attrs = list_make1(makeString(column->colname));
cxt->fkconstraints = lappend(cxt->fkconstraints, constraint);
break;
case CONSTR_ATTR_DEFERRABLE:
case CONSTR_ATTR_NOT_DEFERRABLE:
case CONSTR_ATTR_DEFERRED:
case CONSTR_ATTR_IMMEDIATE:
/* transformConstraintAttrs took care of these */
break;
default:
elog(ERROR, "unrecognized constraint type: %d",
constraint->contype);
break;
}
if (saw_default && saw_identity)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("both default and identity specified for column \"%s\" of table \"%s\"",
column->colname, cxt->relation->relname),
parser_errposition(cxt->pstate,
constraint->location)));
if (saw_default && saw_generated)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("both default and generation expression specified for column \"%s\" of table \"%s\"",
column->colname, cxt->relation->relname),
parser_errposition(cxt->pstate,
constraint->location)));
if (saw_identity && saw_generated)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("both identity and generation expression specified for column \"%s\" of table \"%s\"",
column->colname, cxt->relation->relname),
parser_errposition(cxt->pstate,
constraint->location)));
}
/*
* If needed, generate ALTER FOREIGN TABLE ALTER COLUMN statement to add
* per-column foreign data wrapper options to this column after creation.
*/
if (column->fdwoptions != NIL)
{
AlterTableStmt *stmt;
AlterTableCmd *cmd;
cmd = makeNode(AlterTableCmd);
cmd->subtype = AT_AlterColumnGenericOptions;
cmd->name = column->colname;
cmd->def = (Node *) column->fdwoptions;
cmd->behavior = DROP_RESTRICT;
cmd->missing_ok = false;
stmt = makeNode(AlterTableStmt);
stmt->relation = cxt->relation;
stmt->cmds = NIL;
stmt->objtype = OBJECT_FOREIGN_TABLE;
stmt->cmds = lappend(stmt->cmds, cmd);
cxt->alist = lappend(cxt->alist, stmt);
}
}
/*
* transformTableConstraint
* transform a Constraint node within CREATE TABLE or ALTER TABLE
*/
static void
transformTableConstraint(CreateStmtContext *cxt, Constraint *constraint)
{
switch (constraint->contype)
{
case CONSTR_PRIMARY:
if (cxt->isforeign)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("primary key constraints are not supported on foreign tables"),
parser_errposition(cxt->pstate,
constraint->location)));
cxt->ixconstraints = lappend(cxt->ixconstraints, constraint);
break;
case CONSTR_UNIQUE:
if (cxt->isforeign)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("unique constraints are not supported on foreign tables"),
parser_errposition(cxt->pstate,
constraint->location)));
cxt->ixconstraints = lappend(cxt->ixconstraints, constraint);
break;
case CONSTR_EXCLUSION:
if (cxt->isforeign)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("exclusion constraints are not supported on foreign tables"),
parser_errposition(cxt->pstate,
constraint->location)));
Implement table partitioning. Table partitioning is like table inheritance and reuses much of the existing infrastructure, but there are some important differences. The parent is called a partitioned table and is always empty; it may not have indexes or non-inherited constraints, since those make no sense for a relation with no data of its own. The children are called partitions and contain all of the actual data. Each partition has an implicit partitioning constraint. Multiple inheritance is not allowed, and partitioning and inheritance can't be mixed. Partitions can't have extra columns and may not allow nulls unless the parent does. Tuples inserted into the parent are automatically routed to the correct partition, so tuple-routing ON INSERT triggers are not needed. Tuple routing isn't yet supported for partitions which are foreign tables, and it doesn't handle updates that cross partition boundaries. Currently, tables can be range-partitioned or list-partitioned. List partitioning is limited to a single column, but range partitioning can involve multiple columns. A partitioning "column" can be an expression. Because table partitioning is less general than table inheritance, it is hoped that it will be easier to reason about properties of partitions, and therefore that this will serve as a better foundation for a variety of possible optimizations, including query planner optimizations. The tuple routing based which this patch does based on the implicit partitioning constraints is an example of this, but it seems likely that many other useful optimizations are also possible. Amit Langote, reviewed and tested by Robert Haas, Ashutosh Bapat, Amit Kapila, Rajkumar Raghuwanshi, Corey Huinker, Jaime Casanova, Rushabh Lathia, Erik Rijkers, among others. Minor revisions by me.
2016-12-07 19:17:43 +01:00
if (cxt->ispartitioned)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("exclusion constraints are not supported on partitioned tables"),
parser_errposition(cxt->pstate,
constraint->location)));
cxt->ixconstraints = lappend(cxt->ixconstraints, constraint);
break;
case CONSTR_CHECK:
cxt->ckconstraints = lappend(cxt->ckconstraints, constraint);
break;
case CONSTR_FOREIGN:
if (cxt->isforeign)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("foreign key constraints are not supported on foreign tables"),
parser_errposition(cxt->pstate,
constraint->location)));
cxt->fkconstraints = lappend(cxt->fkconstraints, constraint);
break;
case CONSTR_NULL:
case CONSTR_NOTNULL:
case CONSTR_DEFAULT:
case CONSTR_ATTR_DEFERRABLE:
case CONSTR_ATTR_NOT_DEFERRABLE:
case CONSTR_ATTR_DEFERRED:
case CONSTR_ATTR_IMMEDIATE:
elog(ERROR, "invalid context for constraint type %d",
constraint->contype);
break;
default:
elog(ERROR, "unrecognized constraint type: %d",
constraint->contype);
break;
}
}
/*
* transformTableLikeClause
*
* Change the LIKE <srctable> portion of a CREATE TABLE statement into
* column definitions that recreate the user defined column portions of
* <srctable>. Also, if there are any LIKE options that we can't fully
* process at this point, add the TableLikeClause to cxt->likeclauses, which
* will cause utility.c to call expandTableLikeClause() after the new
* table has been created.
*/
static void
transformTableLikeClause(CreateStmtContext *cxt, TableLikeClause *table_like_clause)
{
AttrNumber parent_attno;
Relation relation;
TupleDesc tupleDesc;
AclResult aclresult;
char *comment;
ParseCallbackState pcbstate;
setup_parser_errposition_callback(&pcbstate, cxt->pstate,
table_like_clause->relation->location);
/* we could support LIKE in many cases, but worry about it another day */
if (cxt->isforeign)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
2013-08-08 04:48:40 +02:00
errmsg("LIKE is not supported for creating foreign tables")));
/* Open the relation referenced by the LIKE clause */
relation = relation_openrv(table_like_clause->relation, AccessShareLock);
Prevent CREATE TABLE LIKE/INHERITS from (mis) copying whole-row Vars. If a CHECK constraint or index definition contained a whole-row Var (that is, "table.*"), an attempt to copy that definition via CREATE TABLE LIKE or table inheritance produced incorrect results: the copied Var still claimed to have the rowtype of the source table, rather than the created table. For the LIKE case, it seems reasonable to just throw error for this situation, since the point of LIKE is that the new table is not permanently coupled to the old, so there's no reason to assume its rowtype will stay compatible. In the inheritance case, we should ideally allow such constraints, but doing so will require nontrivial refactoring of CREATE TABLE processing (because we'd need to know the OID of the new table's rowtype before we adjust inherited CHECK constraints). In view of the lack of previous complaints, that doesn't seem worth the risk in a back-patched bug fix, so just make it throw error for the inheritance case as well. Along the way, replace change_varattnos_of_a_node() with a more robust function map_variable_attnos(), which is capable of being extended to handle insertion of ConvertRowtypeExpr whenever we get around to fixing the inheritance case nicely, and in the meantime it returns a failure indication to the caller so that a helpful message with some context can be thrown. Also, this code will do the right thing with subselects (if we ever allow them in CHECK or indexes), and it range-checks varattnos before using them to index into the map array. Per report from Sergey Konoplev. Back-patch to all supported branches.
2012-06-30 22:43:50 +02:00
if (relation->rd_rel->relkind != RELKIND_RELATION &&
relation->rd_rel->relkind != RELKIND_VIEW &&
relation->rd_rel->relkind != RELKIND_MATVIEW &&
Prevent CREATE TABLE LIKE/INHERITS from (mis) copying whole-row Vars. If a CHECK constraint or index definition contained a whole-row Var (that is, "table.*"), an attempt to copy that definition via CREATE TABLE LIKE or table inheritance produced incorrect results: the copied Var still claimed to have the rowtype of the source table, rather than the created table. For the LIKE case, it seems reasonable to just throw error for this situation, since the point of LIKE is that the new table is not permanently coupled to the old, so there's no reason to assume its rowtype will stay compatible. In the inheritance case, we should ideally allow such constraints, but doing so will require nontrivial refactoring of CREATE TABLE processing (because we'd need to know the OID of the new table's rowtype before we adjust inherited CHECK constraints). In view of the lack of previous complaints, that doesn't seem worth the risk in a back-patched bug fix, so just make it throw error for the inheritance case as well. Along the way, replace change_varattnos_of_a_node() with a more robust function map_variable_attnos(), which is capable of being extended to handle insertion of ConvertRowtypeExpr whenever we get around to fixing the inheritance case nicely, and in the meantime it returns a failure indication to the caller so that a helpful message with some context can be thrown. Also, this code will do the right thing with subselects (if we ever allow them in CHECK or indexes), and it range-checks varattnos before using them to index into the map array. Per report from Sergey Konoplev. Back-patch to all supported branches.
2012-06-30 22:43:50 +02:00
relation->rd_rel->relkind != RELKIND_COMPOSITE_TYPE &&
Implement table partitioning. Table partitioning is like table inheritance and reuses much of the existing infrastructure, but there are some important differences. The parent is called a partitioned table and is always empty; it may not have indexes or non-inherited constraints, since those make no sense for a relation with no data of its own. The children are called partitions and contain all of the actual data. Each partition has an implicit partitioning constraint. Multiple inheritance is not allowed, and partitioning and inheritance can't be mixed. Partitions can't have extra columns and may not allow nulls unless the parent does. Tuples inserted into the parent are automatically routed to the correct partition, so tuple-routing ON INSERT triggers are not needed. Tuple routing isn't yet supported for partitions which are foreign tables, and it doesn't handle updates that cross partition boundaries. Currently, tables can be range-partitioned or list-partitioned. List partitioning is limited to a single column, but range partitioning can involve multiple columns. A partitioning "column" can be an expression. Because table partitioning is less general than table inheritance, it is hoped that it will be easier to reason about properties of partitions, and therefore that this will serve as a better foundation for a variety of possible optimizations, including query planner optimizations. The tuple routing based which this patch does based on the implicit partitioning constraints is an example of this, but it seems likely that many other useful optimizations are also possible. Amit Langote, reviewed and tested by Robert Haas, Ashutosh Bapat, Amit Kapila, Rajkumar Raghuwanshi, Corey Huinker, Jaime Casanova, Rushabh Lathia, Erik Rijkers, among others. Minor revisions by me.
2016-12-07 19:17:43 +01:00
relation->rd_rel->relkind != RELKIND_FOREIGN_TABLE &&
relation->rd_rel->relkind != RELKIND_PARTITIONED_TABLE)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("relation \"%s\" is invalid in LIKE clause",
RelationGetRelationName(relation)),
errdetail_relkind_not_supported(relation->rd_rel->relkind)));
cancel_parser_errposition_callback(&pcbstate);
/*
* Check for privileges
*/
if (relation->rd_rel->relkind == RELKIND_COMPOSITE_TYPE)
{
aclresult = object_aclcheck(TypeRelationId, relation->rd_rel->reltype, GetUserId(),
ACL_USAGE);
if (aclresult != ACLCHECK_OK)
aclcheck_error(aclresult, OBJECT_TYPE,
RelationGetRelationName(relation));
}
else
{
aclresult = pg_class_aclcheck(RelationGetRelid(relation), GetUserId(),
ACL_SELECT);
if (aclresult != ACLCHECK_OK)
aclcheck_error(aclresult, get_relkind_objtype(relation->rd_rel->relkind),
RelationGetRelationName(relation));
}
tupleDesc = RelationGetDescr(relation);
/*
* Insert the copied attributes into the cxt for the new table definition.
* We must do this now so that they appear in the table in the relative
* position where the LIKE clause is, as required by SQL99.
*/
for (parent_attno = 1; parent_attno <= tupleDesc->natts;
parent_attno++)
{
Form_pg_attribute attribute = TupleDescAttr(tupleDesc,
parent_attno - 1);
char *attributeName = NameStr(attribute->attname);
ColumnDef *def;
/*
* Ignore dropped columns in the parent.
*/
if (attribute->attisdropped)
continue;
/*
* Create a new column, which is marked as NOT inherited.
*
* For constraints, ONLY the NOT NULL constraint is inherited by the
* new column definition per SQL99.
*/
def = makeNode(ColumnDef);
def->colname = pstrdup(attributeName);
def->typeName = makeTypeNameFromOid(attribute->atttypid,
Remove collation information from TypeName, where it does not belong. The initial collations patch treated a COLLATE spec as part of a TypeName, following what can only be described as brain fade on the part of the SQL committee. It's a lot more reasonable to treat COLLATE as a syntactically separate object, so that it can be added in only the productions where it actually belongs, rather than needing to reject it in a boatload of places where it doesn't belong (something the original patch mostly failed to do). In addition this change lets us meet the spec's requirement to allow COLLATE anywhere in the clauses of a ColumnDef, and it avoids unfriendly behavior for constructs such as "foo::type COLLATE collation". To do this, pull collation information out of TypeName and put it in ColumnDef instead, thus reverting most of the collation-related changes in parse_type.c's API. I made one additional structural change, which was to use a ColumnDef as an intermediate node in AT_AlterColumnType AlterTableCmd nodes. This provides enough room to get rid of the "transform" wart in AlterTableCmd too, since the ColumnDef can carry the USING expression easily enough. Also fix some other minor bugs that have crept in in the same areas, like failure to copy recently-added fields of ColumnDef in copyfuncs.c. While at it, document the formerly secret ability to specify a collation in ALTER TABLE ALTER COLUMN TYPE, ALTER TYPE ADD ATTRIBUTE, and ALTER TYPE ALTER ATTRIBUTE TYPE; and correct some misstatements about what the default collation selection will be when COLLATE is omitted. BTW, the three-parameter form of format_type() should go away too, since it just contributes to the confusion in this area; but I'll do that in a separate patch.
2011-03-10 04:38:52 +01:00
attribute->atttypmod);
def->inhcount = 0;
def->is_local = true;
def->is_not_null = attribute->attnotnull;
Remove collation information from TypeName, where it does not belong. The initial collations patch treated a COLLATE spec as part of a TypeName, following what can only be described as brain fade on the part of the SQL committee. It's a lot more reasonable to treat COLLATE as a syntactically separate object, so that it can be added in only the productions where it actually belongs, rather than needing to reject it in a boatload of places where it doesn't belong (something the original patch mostly failed to do). In addition this change lets us meet the spec's requirement to allow COLLATE anywhere in the clauses of a ColumnDef, and it avoids unfriendly behavior for constructs such as "foo::type COLLATE collation". To do this, pull collation information out of TypeName and put it in ColumnDef instead, thus reverting most of the collation-related changes in parse_type.c's API. I made one additional structural change, which was to use a ColumnDef as an intermediate node in AT_AlterColumnType AlterTableCmd nodes. This provides enough room to get rid of the "transform" wart in AlterTableCmd too, since the ColumnDef can carry the USING expression easily enough. Also fix some other minor bugs that have crept in in the same areas, like failure to copy recently-added fields of ColumnDef in copyfuncs.c. While at it, document the formerly secret ability to specify a collation in ALTER TABLE ALTER COLUMN TYPE, ALTER TYPE ADD ATTRIBUTE, and ALTER TYPE ALTER ATTRIBUTE TYPE; and correct some misstatements about what the default collation selection will be when COLLATE is omitted. BTW, the three-parameter form of format_type() should go away too, since it just contributes to the confusion in this area; but I'll do that in a separate patch.
2011-03-10 04:38:52 +01:00
def->is_from_type = false;
def->storage = 0;
def->raw_default = NULL;
def->cooked_default = NULL;
Remove collation information from TypeName, where it does not belong. The initial collations patch treated a COLLATE spec as part of a TypeName, following what can only be described as brain fade on the part of the SQL committee. It's a lot more reasonable to treat COLLATE as a syntactically separate object, so that it can be added in only the productions where it actually belongs, rather than needing to reject it in a boatload of places where it doesn't belong (something the original patch mostly failed to do). In addition this change lets us meet the spec's requirement to allow COLLATE anywhere in the clauses of a ColumnDef, and it avoids unfriendly behavior for constructs such as "foo::type COLLATE collation". To do this, pull collation information out of TypeName and put it in ColumnDef instead, thus reverting most of the collation-related changes in parse_type.c's API. I made one additional structural change, which was to use a ColumnDef as an intermediate node in AT_AlterColumnType AlterTableCmd nodes. This provides enough room to get rid of the "transform" wart in AlterTableCmd too, since the ColumnDef can carry the USING expression easily enough. Also fix some other minor bugs that have crept in in the same areas, like failure to copy recently-added fields of ColumnDef in copyfuncs.c. While at it, document the formerly secret ability to specify a collation in ALTER TABLE ALTER COLUMN TYPE, ALTER TYPE ADD ATTRIBUTE, and ALTER TYPE ALTER ATTRIBUTE TYPE; and correct some misstatements about what the default collation selection will be when COLLATE is omitted. BTW, the three-parameter form of format_type() should go away too, since it just contributes to the confusion in this area; but I'll do that in a separate patch.
2011-03-10 04:38:52 +01:00
def->collClause = NULL;
def->collOid = attribute->attcollation;
def->constraints = NIL;
def->location = -1;
/*
* Add to column list
*/
cxt->columns = lappend(cxt->columns, def);
/*
* Although we don't transfer the column's default/generation
* expression now, we need to mark it GENERATED if appropriate.
*/
if (attribute->atthasdef && attribute->attgenerated &&
(table_like_clause->options & CREATE_TABLE_LIKE_GENERATED))
def->generated = attribute->attgenerated;
/*
* Copy identity if requested
*/
if (attribute->attidentity &&
(table_like_clause->options & CREATE_TABLE_LIKE_IDENTITY))
{
Oid seq_relid;
List *seq_options;
/*
* find sequence owned by old column; extract sequence parameters;
* build new create sequence command
*/
seq_relid = getIdentitySequence(RelationGetRelid(relation), attribute->attnum, false);
seq_options = sequence_options(seq_relid);
generateSerialExtraStmts(cxt, def,
Restructure ALTER TABLE execution to fix assorted bugs. We've had numerous bug reports about how (1) IF NOT EXISTS clauses in ALTER TABLE don't behave as-expected, and (2) combining certain actions into one ALTER TABLE doesn't work, though executing the same actions as separate statements does. This patch cleans up all of the cases so far reported from the field, though there are still some oddities associated with identity columns. The core problem behind all of these bugs is that we do parse analysis of ALTER TABLE subcommands too soon, before starting execution of the statement. The root of the bugs in group (1) is that parse analysis schedules derived commands (such as a CREATE SEQUENCE for a serial column) before it's known whether the IF NOT EXISTS clause should cause a subcommand to be skipped. The root of the bugs in group (2) is that earlier subcommands may change the catalog state that later subcommands need to be parsed against. Hence, postpone parse analysis of ALTER TABLE's subcommands, and do that one subcommand at a time, during "phase 2" of ALTER TABLE which is the phase that does catalog rewrites. Thus the catalog effects of earlier subcommands are already visible when we analyze later ones. (The sole exception is that we do parse analysis for ALTER COLUMN TYPE subcommands during phase 1, so that their USING expressions can be parsed against the table's original state, which is what we need. Arguably, these bugs stem from falsely concluding that because ALTER COLUMN TYPE must do early parse analysis, every other command subtype can too.) This means that ALTER TABLE itself must deal with execution of any non-ALTER-TABLE derived statements that are generated by parse analysis. Add a suitable entry point to utility.c to accept those recursive calls, and create a struct to pass through the information needed by the recursive call, rather than making the argument lists of AlterTable() and friends even longer. Getting this to work correctly required a little bit of fiddling with the subcommand pass structure, in particular breaking up AT_PASS_ADD_CONSTR into multiple passes. But otherwise it's mostly a pretty straightforward application of the above ideas. Fixing the residual issues for identity columns requires refactoring of where the dependency link from an identity column to its sequence gets set up. So that seems like suitable material for a separate patch, especially since this one is pretty big already. Discussion: https://postgr.es/m/10365.1558909428@sss.pgh.pa.us
2020-01-16 00:49:24 +01:00
InvalidOid, seq_options,
true, false,
NULL, NULL);
def->identity = attribute->attidentity;
}
/* Likewise, copy storage if requested */
if (table_like_clause->options & CREATE_TABLE_LIKE_STORAGE)
def->storage = attribute->attstorage;
else
def->storage = 0;
Allow configurable LZ4 TOAST compression. There is now a per-column COMPRESSION option which can be set to pglz (the default, and the only option in up until now) or lz4. Or, if you like, you can set the new default_toast_compression GUC to lz4, and then that will be the default for new table columns for which no value is specified. We don't have lz4 support in the PostgreSQL code, so to use lz4 compression, PostgreSQL must be built --with-lz4. In general, TOAST compression means compression of individual column values, not the whole tuple, and those values can either be compressed inline within the tuple or compressed and then stored externally in the TOAST table, so those properties also apply to this feature. Prior to this commit, a TOAST pointer has two unused bits as part of the va_extsize field, and a compessed datum has two unused bits as part of the va_rawsize field. These bits are unused because the length of a varlena is limited to 1GB; we now use them to indicate the compression type that was used. This means we only have bit space for 2 more built-in compresison types, but we could work around that problem, if necessary, by introducing a new vartag_external value for any further types we end up wanting to add. Hopefully, it won't be too important to offer a wide selection of algorithms here, since each one we add not only takes more coding but also adds a build dependency for every packager. Nevertheless, it seems worth doing at least this much, because LZ4 gets better compression than PGLZ with less CPU usage. It's possible for LZ4-compressed datums to leak into composite type values stored on disk, just as it is for PGLZ. It's also possible for LZ4-compressed attributes to be copied into a different table via SQL commands such as CREATE TABLE AS or INSERT .. SELECT. It would be expensive to force such values to be decompressed, so PostgreSQL has never done so. For the same reasons, we also don't force recompression of already-compressed values even if the target table prefers a different compression method than was used for the source data. These architectural decisions are perhaps arguable but revisiting them is well beyond the scope of what seemed possible to do as part of this project. However, it's relatively cheap to recompress as part of VACUUM FULL or CLUSTER, so this commit adjusts those commands to do so, if the configured compression method of the table happens not to match what was used for some column value stored therein. Dilip Kumar. The original patches on which this work was based were written by Ildus Kurbangaliev, and those were patches were based on even earlier work by Nikita Glukhov, but the design has since changed very substantially, since allow a potentially large number of compression methods that could be added and dropped on a running system proved too problematic given some of the architectural issues mentioned above; the choice of which specific compression method to add first is now different; and a lot of the code has been heavily refactored. More recently, Justin Przyby helped quite a bit with testing and reviewing and this version also includes some code contributions from him. Other design input and review from Tomas Vondra, Álvaro Herrera, Andres Freund, Oleg Bartunov, Alexander Korotkov, and me. Discussion: http://postgr.es/m/20170907194236.4cefce96%40wp.localdomain Discussion: http://postgr.es/m/CAFiTN-uUpX3ck%3DK0mLEk-G_kUQY%3DSNOTeqdaNRR9FMdQrHKebw%40mail.gmail.com
2021-03-19 20:10:38 +01:00
/* Likewise, copy compression if requested */
if ((table_like_clause->options & CREATE_TABLE_LIKE_COMPRESSION) != 0
&& CompressionMethodIsValid(attribute->attcompression))
def->compression =
pstrdup(GetCompressionMethodName(attribute->attcompression));
else
def->compression = NULL;
/* Likewise, copy comment if requested */
if ((table_like_clause->options & CREATE_TABLE_LIKE_COMMENTS) &&
(comment = GetComment(attribute->attrelid,
RelationRelationId,
attribute->attnum)) != NULL)
{
CommentStmt *stmt = makeNode(CommentStmt);
stmt->objtype = OBJECT_COLUMN;
stmt->object = (Node *) list_make3(makeString(cxt->relation->schemaname),
makeString(cxt->relation->relname),
makeString(def->colname));
stmt->comment = comment;
cxt->alist = lappend(cxt->alist, stmt);
}
}
/*
* We cannot yet deal with defaults, CHECK constraints, or indexes, since
* we don't yet know what column numbers the copied columns will have in
* the finished table. If any of those options are specified, add the
* LIKE clause to cxt->likeclauses so that expandTableLikeClause will be
* called after we do know that. Also, remember the relation OID so that
* expandTableLikeClause is certain to open the same table.
*/
if (table_like_clause->options &
(CREATE_TABLE_LIKE_DEFAULTS |
CREATE_TABLE_LIKE_GENERATED |
CREATE_TABLE_LIKE_CONSTRAINTS |
CREATE_TABLE_LIKE_INDEXES))
{
table_like_clause->relationOid = RelationGetRelid(relation);
cxt->likeclauses = lappend(cxt->likeclauses, table_like_clause);
}
/*
* We may copy extended statistics if requested, since the representation
* of CreateStatsStmt doesn't depend on column numbers.
*/
if (table_like_clause->options & CREATE_TABLE_LIKE_STATISTICS)
{
List *parent_extstats;
ListCell *l;
parent_extstats = RelationGetStatExtList(relation);
foreach(l, parent_extstats)
{
Oid parent_stat_oid = lfirst_oid(l);
CreateStatsStmt *stats_stmt;
stats_stmt = generateClonedExtStatsStmt(cxt->relation,
RelationGetRelid(relation),
parent_stat_oid);
/* Copy comment on statistics object, if requested */
if (table_like_clause->options & CREATE_TABLE_LIKE_COMMENTS)
{
comment = GetComment(parent_stat_oid, StatisticExtRelationId, 0);
/*
* We make use of CreateStatsStmt's stxcomment option, so as
* not to need to know now what name the statistics will have.
*/
stats_stmt->stxcomment = comment;
}
cxt->extstats = lappend(cxt->extstats, stats_stmt);
}
list_free(parent_extstats);
}
/*
* Close the parent rel, but keep our AccessShareLock on it until xact
* commit. That will prevent someone else from deleting or ALTERing the
* parent before we can run expandTableLikeClause.
*/
table_close(relation, NoLock);
}
/*
* expandTableLikeClause
*
* Process LIKE options that require knowing the final column numbers
* assigned to the new table's columns. This executes after we have
* run DefineRelation for the new table. It returns a list of utility
* commands that should be run to generate indexes etc.
*/
List *
expandTableLikeClause(RangeVar *heapRel, TableLikeClause *table_like_clause)
{
List *result = NIL;
List *atsubcmds = NIL;
AttrNumber parent_attno;
Relation relation;
Relation childrel;
TupleDesc tupleDesc;
TupleConstr *constr;
AttrMap *attmap;
char *comment;
/*
* Open the relation referenced by the LIKE clause. We should still have
* the table lock obtained by transformTableLikeClause (and this'll throw
* an assertion failure if not). Hence, no need to recheck privileges
* etc. We must open the rel by OID not name, to be sure we get the same
* table.
*/
if (!OidIsValid(table_like_clause->relationOid))
elog(ERROR, "expandTableLikeClause called on untransformed LIKE clause");
relation = relation_open(table_like_clause->relationOid, NoLock);
tupleDesc = RelationGetDescr(relation);
constr = tupleDesc->constr;
/*
* Open the newly-created child relation; we have lock on that too.
*/
childrel = relation_openrv(heapRel, NoLock);
/*
* Construct a map from the LIKE relation's attnos to the child rel's.
* This re-checks type match etc, although it shouldn't be possible to
* have a failure since both tables are locked.
*/
attmap = build_attrmap_by_name(RelationGetDescr(childrel),
tupleDesc,
false);
/*
* Process defaults, if required.
*/
if ((table_like_clause->options &
(CREATE_TABLE_LIKE_DEFAULTS | CREATE_TABLE_LIKE_GENERATED)) &&
constr != NULL)
{
for (parent_attno = 1; parent_attno <= tupleDesc->natts;
parent_attno++)
{
Form_pg_attribute attribute = TupleDescAttr(tupleDesc,
parent_attno - 1);
/*
* Ignore dropped columns in the parent.
*/
if (attribute->attisdropped)
continue;
/*
* Copy default, if present and it should be copied. We have
* separate options for plain default expressions and GENERATED
* defaults.
*/
if (attribute->atthasdef &&
(attribute->attgenerated ?
(table_like_clause->options & CREATE_TABLE_LIKE_GENERATED) :
(table_like_clause->options & CREATE_TABLE_LIKE_DEFAULTS)))
{
Node *this_default = NULL;
Clean up treatment of missing default and CHECK-constraint records. Andrew Gierth reported that it's possible to crash the backend if no pg_attrdef record is found to match an attribute that has atthasdef set. AttrDefaultFetch warns about this situation, but then leaves behind a relation tupdesc that has null "adbin" pointer(s), which most places don't guard against. We considered promoting the warning to an error, but throwing errors during relcache load is pretty drastic: it effectively locks one out of using the relation at all. What seems better is to leave the load-time behavior as a warning, but then throw an error in any code path that wants to use a default and can't find it. This confines the error to a subset of INSERT/UPDATE operations on the table, and in particular will at least allow a pg_dump to succeed. Also, we should fix AttrDefaultFetch to not leave any null pointers in the tupdesc, because that just creates an untested bug hazard. While at it, apply the same philosophy of "warn at load, throw error only upon use of the known-missing info" to CHECK constraints. CheckConstraintFetch is very nearly the same logic as AttrDefaultFetch, but for reasons lost in the mists of time, it was throwing ERROR for the same cases that AttrDefaultFetch treats as WARNING. Make the two functions more nearly alike. In passing, get rid of potentially-O(N^2) loops in equalTupleDesc by making AttrDefaultFetch sort the entries after fetching them, so that equalTupleDesc can assume that entries in two equal tupdescs must be in matching order. (CheckConstraintFetch already was sorting CHECK constraints, but equalTupleDesc hadn't been told about it.) There's some argument for back-patching this, but with such a small number of field reports, I'm content to fix it in HEAD. Discussion: https://postgr.es/m/87pmzaq4gx.fsf@news-spur.riddles.org.uk
2021-04-06 16:34:37 +02:00
AttrDefault *attrdef = constr->defval;
AlterTableCmd *atsubcmd;
bool found_whole_row;
/* Find default in constraint structure */
for (int i = 0; i < constr->num_defval; i++)
{
if (attrdef[i].adnum == parent_attno)
{
this_default = stringToNode(attrdef[i].adbin);
break;
}
}
Clean up treatment of missing default and CHECK-constraint records. Andrew Gierth reported that it's possible to crash the backend if no pg_attrdef record is found to match an attribute that has atthasdef set. AttrDefaultFetch warns about this situation, but then leaves behind a relation tupdesc that has null "adbin" pointer(s), which most places don't guard against. We considered promoting the warning to an error, but throwing errors during relcache load is pretty drastic: it effectively locks one out of using the relation at all. What seems better is to leave the load-time behavior as a warning, but then throw an error in any code path that wants to use a default and can't find it. This confines the error to a subset of INSERT/UPDATE operations on the table, and in particular will at least allow a pg_dump to succeed. Also, we should fix AttrDefaultFetch to not leave any null pointers in the tupdesc, because that just creates an untested bug hazard. While at it, apply the same philosophy of "warn at load, throw error only upon use of the known-missing info" to CHECK constraints. CheckConstraintFetch is very nearly the same logic as AttrDefaultFetch, but for reasons lost in the mists of time, it was throwing ERROR for the same cases that AttrDefaultFetch treats as WARNING. Make the two functions more nearly alike. In passing, get rid of potentially-O(N^2) loops in equalTupleDesc by making AttrDefaultFetch sort the entries after fetching them, so that equalTupleDesc can assume that entries in two equal tupdescs must be in matching order. (CheckConstraintFetch already was sorting CHECK constraints, but equalTupleDesc hadn't been told about it.) There's some argument for back-patching this, but with such a small number of field reports, I'm content to fix it in HEAD. Discussion: https://postgr.es/m/87pmzaq4gx.fsf@news-spur.riddles.org.uk
2021-04-06 16:34:37 +02:00
if (this_default == NULL)
elog(ERROR, "default expression not found for attribute %d of relation \"%s\"",
parent_attno, RelationGetRelationName(relation));
atsubcmd = makeNode(AlterTableCmd);
atsubcmd->subtype = AT_CookedColumnDefault;
atsubcmd->num = attmap->attnums[parent_attno - 1];
atsubcmd->def = map_variable_attnos(this_default,
1, 0,
attmap,
InvalidOid,
&found_whole_row);
/*
* Prevent this for the same reason as for constraints below.
* Note that defaults cannot contain any vars, so it's OK that
* the error message refers to generated columns.
*/
if (found_whole_row)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot convert whole-row table reference"),
errdetail("Generation expression for column \"%s\" contains a whole-row reference to table \"%s\".",
NameStr(attribute->attname),
RelationGetRelationName(relation))));
atsubcmds = lappend(atsubcmds, atsubcmd);
}
}
}
/*
* Copy CHECK constraints if requested, being careful to adjust attribute
Prevent CREATE TABLE LIKE/INHERITS from (mis) copying whole-row Vars. If a CHECK constraint or index definition contained a whole-row Var (that is, "table.*"), an attempt to copy that definition via CREATE TABLE LIKE or table inheritance produced incorrect results: the copied Var still claimed to have the rowtype of the source table, rather than the created table. For the LIKE case, it seems reasonable to just throw error for this situation, since the point of LIKE is that the new table is not permanently coupled to the old, so there's no reason to assume its rowtype will stay compatible. In the inheritance case, we should ideally allow such constraints, but doing so will require nontrivial refactoring of CREATE TABLE processing (because we'd need to know the OID of the new table's rowtype before we adjust inherited CHECK constraints). In view of the lack of previous complaints, that doesn't seem worth the risk in a back-patched bug fix, so just make it throw error for the inheritance case as well. Along the way, replace change_varattnos_of_a_node() with a more robust function map_variable_attnos(), which is capable of being extended to handle insertion of ConvertRowtypeExpr whenever we get around to fixing the inheritance case nicely, and in the meantime it returns a failure indication to the caller so that a helpful message with some context can be thrown. Also, this code will do the right thing with subselects (if we ever allow them in CHECK or indexes), and it range-checks varattnos before using them to index into the map array. Per report from Sergey Konoplev. Back-patch to all supported branches.
2012-06-30 22:43:50 +02:00
* numbers so they match the child.
*/
if ((table_like_clause->options & CREATE_TABLE_LIKE_CONSTRAINTS) &&
constr != NULL)
{
int ccnum;
for (ccnum = 0; ccnum < constr->num_check; ccnum++)
{
char *ccname = constr->check[ccnum].ccname;
char *ccbin = constr->check[ccnum].ccbin;
bool ccnoinherit = constr->check[ccnum].ccnoinherit;
Prevent CREATE TABLE LIKE/INHERITS from (mis) copying whole-row Vars. If a CHECK constraint or index definition contained a whole-row Var (that is, "table.*"), an attempt to copy that definition via CREATE TABLE LIKE or table inheritance produced incorrect results: the copied Var still claimed to have the rowtype of the source table, rather than the created table. For the LIKE case, it seems reasonable to just throw error for this situation, since the point of LIKE is that the new table is not permanently coupled to the old, so there's no reason to assume its rowtype will stay compatible. In the inheritance case, we should ideally allow such constraints, but doing so will require nontrivial refactoring of CREATE TABLE processing (because we'd need to know the OID of the new table's rowtype before we adjust inherited CHECK constraints). In view of the lack of previous complaints, that doesn't seem worth the risk in a back-patched bug fix, so just make it throw error for the inheritance case as well. Along the way, replace change_varattnos_of_a_node() with a more robust function map_variable_attnos(), which is capable of being extended to handle insertion of ConvertRowtypeExpr whenever we get around to fixing the inheritance case nicely, and in the meantime it returns a failure indication to the caller so that a helpful message with some context can be thrown. Also, this code will do the right thing with subselects (if we ever allow them in CHECK or indexes), and it range-checks varattnos before using them to index into the map array. Per report from Sergey Konoplev. Back-patch to all supported branches.
2012-06-30 22:43:50 +02:00
Node *ccbin_node;
bool found_whole_row;
Constraint *n;
AlterTableCmd *atsubcmd;
Prevent CREATE TABLE LIKE/INHERITS from (mis) copying whole-row Vars. If a CHECK constraint or index definition contained a whole-row Var (that is, "table.*"), an attempt to copy that definition via CREATE TABLE LIKE or table inheritance produced incorrect results: the copied Var still claimed to have the rowtype of the source table, rather than the created table. For the LIKE case, it seems reasonable to just throw error for this situation, since the point of LIKE is that the new table is not permanently coupled to the old, so there's no reason to assume its rowtype will stay compatible. In the inheritance case, we should ideally allow such constraints, but doing so will require nontrivial refactoring of CREATE TABLE processing (because we'd need to know the OID of the new table's rowtype before we adjust inherited CHECK constraints). In view of the lack of previous complaints, that doesn't seem worth the risk in a back-patched bug fix, so just make it throw error for the inheritance case as well. Along the way, replace change_varattnos_of_a_node() with a more robust function map_variable_attnos(), which is capable of being extended to handle insertion of ConvertRowtypeExpr whenever we get around to fixing the inheritance case nicely, and in the meantime it returns a failure indication to the caller so that a helpful message with some context can be thrown. Also, this code will do the right thing with subselects (if we ever allow them in CHECK or indexes), and it range-checks varattnos before using them to index into the map array. Per report from Sergey Konoplev. Back-patch to all supported branches.
2012-06-30 22:43:50 +02:00
ccbin_node = map_variable_attnos(stringToNode(ccbin),
1, 0,
attmap,
InvalidOid, &found_whole_row);
Prevent CREATE TABLE LIKE/INHERITS from (mis) copying whole-row Vars. If a CHECK constraint or index definition contained a whole-row Var (that is, "table.*"), an attempt to copy that definition via CREATE TABLE LIKE or table inheritance produced incorrect results: the copied Var still claimed to have the rowtype of the source table, rather than the created table. For the LIKE case, it seems reasonable to just throw error for this situation, since the point of LIKE is that the new table is not permanently coupled to the old, so there's no reason to assume its rowtype will stay compatible. In the inheritance case, we should ideally allow such constraints, but doing so will require nontrivial refactoring of CREATE TABLE processing (because we'd need to know the OID of the new table's rowtype before we adjust inherited CHECK constraints). In view of the lack of previous complaints, that doesn't seem worth the risk in a back-patched bug fix, so just make it throw error for the inheritance case as well. Along the way, replace change_varattnos_of_a_node() with a more robust function map_variable_attnos(), which is capable of being extended to handle insertion of ConvertRowtypeExpr whenever we get around to fixing the inheritance case nicely, and in the meantime it returns a failure indication to the caller so that a helpful message with some context can be thrown. Also, this code will do the right thing with subselects (if we ever allow them in CHECK or indexes), and it range-checks varattnos before using them to index into the map array. Per report from Sergey Konoplev. Back-patch to all supported branches.
2012-06-30 22:43:50 +02:00
/*
* We reject whole-row variables because the whole point of LIKE
* is that the new table's rowtype might later diverge from the
* parent's. So, while translation might be possible right now,
* it wouldn't be possible to guarantee it would work in future.
*/
if (found_whole_row)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot convert whole-row table reference"),
errdetail("Constraint \"%s\" contains a whole-row reference to table \"%s\".",
ccname,
RelationGetRelationName(relation))));
n = makeNode(Constraint);
n->contype = CONSTR_CHECK;
n->conname = pstrdup(ccname);
n->location = -1;
n->is_no_inherit = ccnoinherit;
n->raw_expr = NULL;
n->cooked_expr = nodeToString(ccbin_node);
/* We can skip validation, since the new table should be empty. */
n->skip_validation = true;
n->initially_valid = true;
atsubcmd = makeNode(AlterTableCmd);
atsubcmd->subtype = AT_AddConstraint;
atsubcmd->def = (Node *) n;
atsubcmds = lappend(atsubcmds, atsubcmd);
/* Copy comment on constraint */
if ((table_like_clause->options & CREATE_TABLE_LIKE_COMMENTS) &&
(comment = GetComment(get_relation_constraint_oid(RelationGetRelid(relation),
n->conname, false),
ConstraintRelationId,
0)) != NULL)
{
CommentStmt *stmt = makeNode(CommentStmt);
stmt->objtype = OBJECT_TABCONSTRAINT;
stmt->object = (Node *) list_make3(makeString(heapRel->schemaname),
makeString(heapRel->relname),
makeString(n->conname));
stmt->comment = comment;
result = lappend(result, stmt);
}
}
}
/*
* If we generated any ALTER TABLE actions above, wrap them into a single
* ALTER TABLE command. Stick it at the front of the result, so it runs
* before any CommentStmts we made above.
*/
if (atsubcmds)
{
AlterTableStmt *atcmd = makeNode(AlterTableStmt);
atcmd->relation = copyObject(heapRel);
atcmd->cmds = atsubcmds;
atcmd->objtype = OBJECT_TABLE;
atcmd->missing_ok = false;
result = lcons(atcmd, result);
}
/*
* Process indexes if required.
*/
if ((table_like_clause->options & CREATE_TABLE_LIKE_INDEXES) &&
relation->rd_rel->relhasindex)
{
List *parent_indexes;
ListCell *l;
parent_indexes = RelationGetIndexList(relation);
foreach(l, parent_indexes)
{
Oid parent_index_oid = lfirst_oid(l);
Relation parent_index;
IndexStmt *index_stmt;
parent_index = index_open(parent_index_oid, AccessShareLock);
/* Build CREATE INDEX statement to recreate the parent_index */
index_stmt = generateClonedIndexStmt(heapRel,
parent_index,
attmap,
Avoid order-of-execution problems with ALTER TABLE ADD PRIMARY KEY. Up to now, DefineIndex() was responsible for adding attnotnull constraints to the columns of a primary key, in any case where it hadn't been convenient for transformIndexConstraint() to mark those columns as is_not_null. It (or rather its minion index_check_primary_key) did this by executing an ALTER TABLE SET NOT NULL command for the target table. The trouble with this solution is that if we're creating the index due to ALTER TABLE ADD PRIMARY KEY, and the outer ALTER TABLE has additional sub-commands, the inner ALTER TABLE's operations executed at the wrong time with respect to the outer ALTER TABLE's operations. In particular, the inner ALTER would perform a validation scan at a point where the table's storage might be inconsistent with its catalog entries. (This is on the hairy edge of being a security problem, but AFAICS it isn't one because the inner scan would only be interested in the tuples' null bitmaps.) This can result in unexpected failures, such as the one seen in bug #15580 from Allison Kaptur. To fix, let's remove the attempt to do SET NOT NULL from DefineIndex(), reducing index_check_primary_key's role to verifying that the columns are already not null. (It shouldn't ever see such a case, but it seems wise to keep the check for safety.) Instead, make transformIndexConstraint() generate ALTER TABLE SET NOT NULL subcommands to be executed ahead of the ADD PRIMARY KEY operation in every case where it can't force the column to be created already-not-null. This requires only minor surgery in parse_utilcmd.c, and it makes for a much more satisfying spec for transformIndexConstraint(): it's no longer having to take it on faith that someone else will handle addition of NOT NULL constraints. To make that work, we have to move the execution of AT_SetNotNull into an ALTER pass that executes ahead of AT_PASS_ADD_INDEX. I moved it to AT_PASS_COL_ATTRS, and put that after AT_PASS_ADD_COL to avoid failure when the column is being added in the same command. This incidentally fixes a bug in the only previous usage of AT_PASS_COL_ATTRS, for AT_SetIdentity: it didn't work either for a newly-added column. Playing around with this exposed a separate bug in ALTER TABLE ONLY ... ADD PRIMARY KEY for partitioned tables. The intent of the ONLY modifier in that context is to prevent doing anything that would require holding lock for a long time --- but the implied SET NOT NULL would recurse to the child partitions, and do an expensive validation scan for any child where the column(s) were not already NOT NULL. To fix that, invent a new ALTER subcommand AT_CheckNotNull that just insists that a child column be already NOT NULL, and apply that, not AT_SetNotNull, when recursing to children in this scenario. This results in a slightly laxer definition of ALTER TABLE ONLY ... SET NOT NULL for partitioned tables, too: that command will now work as long as all children are already NOT NULL, whereas before it just threw up its hands if there were any partitions. In passing, clean up the API of generateClonedIndexStmt(): remove a useless argument, ensure that the output argument is not left undefined, update the header comment. A small side effect of this change is that no-such-column errors in ALTER TABLE ADD PRIMARY KEY now produce a different message that includes the table name, because they are now detected by the SET NOT NULL step which has historically worded its error that way. That seems fine to me, so I didn't make any effort to avoid the wording change. The basic bug #15580 is of very long standing, and these other bugs aren't new in v12 either. However, this is a pretty significant change in the way ALTER TABLE ADD PRIMARY KEY works. On balance it seems best not to back-patch, at least not till we get some more confidence that this patch has no new bugs. Patch by me, but thanks to Jie Zhang for a preliminary version. Discussion: https://postgr.es/m/15580-d1a6de5a3d65da51@postgresql.org Discussion: https://postgr.es/m/1396E95157071C4EBBA51892C5368521017F2E6E63@G08CNEXMBPEKD02.g08.fujitsu.local
2019-04-23 18:25:27 +02:00
NULL);
/* Copy comment on index, if requested */
if (table_like_clause->options & CREATE_TABLE_LIKE_COMMENTS)
{
comment = GetComment(parent_index_oid, RelationRelationId, 0);
/*
* We make use of IndexStmt's idxcomment option, so as not to
* need to know now what name the index will have.
*/
index_stmt->idxcomment = comment;
}
result = lappend(result, index_stmt);
index_close(parent_index, AccessShareLock);
}
}
/* Done with child rel */
table_close(childrel, NoLock);
/*
* Close the parent rel, but keep our AccessShareLock on it until xact
* commit. That will prevent someone else from deleting or ALTERing the
* parent before the child is committed.
*/
table_close(relation, NoLock);
return result;
}
static void
transformOfType(CreateStmtContext *cxt, TypeName *ofTypename)
{
HeapTuple tuple;
TupleDesc tupdesc;
int i;
Oid ofTypeId;
Assert(ofTypename);
Remove collation information from TypeName, where it does not belong. The initial collations patch treated a COLLATE spec as part of a TypeName, following what can only be described as brain fade on the part of the SQL committee. It's a lot more reasonable to treat COLLATE as a syntactically separate object, so that it can be added in only the productions where it actually belongs, rather than needing to reject it in a boatload of places where it doesn't belong (something the original patch mostly failed to do). In addition this change lets us meet the spec's requirement to allow COLLATE anywhere in the clauses of a ColumnDef, and it avoids unfriendly behavior for constructs such as "foo::type COLLATE collation". To do this, pull collation information out of TypeName and put it in ColumnDef instead, thus reverting most of the collation-related changes in parse_type.c's API. I made one additional structural change, which was to use a ColumnDef as an intermediate node in AT_AlterColumnType AlterTableCmd nodes. This provides enough room to get rid of the "transform" wart in AlterTableCmd too, since the ColumnDef can carry the USING expression easily enough. Also fix some other minor bugs that have crept in in the same areas, like failure to copy recently-added fields of ColumnDef in copyfuncs.c. While at it, document the formerly secret ability to specify a collation in ALTER TABLE ALTER COLUMN TYPE, ALTER TYPE ADD ATTRIBUTE, and ALTER TYPE ALTER ATTRIBUTE TYPE; and correct some misstatements about what the default collation selection will be when COLLATE is omitted. BTW, the three-parameter form of format_type() should go away too, since it just contributes to the confusion in this area; but I'll do that in a separate patch.
2011-03-10 04:38:52 +01:00
tuple = typenameType(NULL, ofTypename, NULL);
check_of_type(tuple);
Remove WITH OIDS support, change oid catalog column visibility. Previously tables declared WITH OIDS, including a significant fraction of the catalog tables, stored the oid column not as a normal column, but as part of the tuple header. This special column was not shown by default, which was somewhat odd, as it's often (consider e.g. pg_class.oid) one of the more important parts of a row. Neither pg_dump nor COPY included the contents of the oid column by default. The fact that the oid column was not an ordinary column necessitated a significant amount of special case code to support oid columns. That already was painful for the existing, but upcoming work aiming to make table storage pluggable, would have required expanding and duplicating that "specialness" significantly. WITH OIDS has been deprecated since 2005 (commit ff02d0a05280e0). Remove it. Removing includes: - CREATE TABLE and ALTER TABLE syntax for declaring the table to be WITH OIDS has been removed (WITH (oids[ = true]) will error out) - pg_dump does not support dumping tables declared WITH OIDS and will issue a warning when dumping one (and ignore the oid column). - restoring an pg_dump archive with pg_restore will warn when restoring a table with oid contents (and ignore the oid column) - COPY will refuse to load binary dump that includes oids. - pg_upgrade will error out when encountering tables declared WITH OIDS, they have to be altered to remove the oid column first. - Functionality to access the oid of the last inserted row (like plpgsql's RESULT_OID, spi's SPI_lastoid, ...) has been removed. The syntax for declaring a table WITHOUT OIDS (or WITH (oids = false) for CREATE TABLE) is still supported. While that requires a bit of support code, it seems unnecessary to break applications / dumps that do not use oids, and are explicit about not using them. The biggest user of WITH OID columns was postgres' catalog. This commit changes all 'magic' oid columns to be columns that are normally declared and stored. To reduce unnecessary query breakage all the newly added columns are still named 'oid', even if a table's column naming scheme would indicate 'reloid' or such. This obviously requires adapting a lot code, mostly replacing oid access via HeapTupleGetOid() with access to the underlying Form_pg_*->oid column. The bootstrap process now assigns oids for all oid columns in genbki.pl that do not have an explicit value (starting at the largest oid previously used), only oids assigned later by oids will be above FirstBootstrapObjectId. As the oid column now is a normal column the special bootstrap syntax for oids has been removed. Oids are not automatically assigned during insertion anymore, all backend code explicitly assigns oids with GetNewOidWithIndex(). For the rare case that insertions into the catalog via SQL are called for the new pg_nextoid() function can be used (which only works on catalog tables). The fact that oid columns on system tables are now normal columns means that they will be included in the set of columns expanded by * (i.e. SELECT * FROM pg_class will now include the table's oid, previously it did not). It'd not technically be hard to hide oid column by default, but that'd mean confusing behavior would either have to be carried forward forever, or it'd cause breakage down the line. While it's not unlikely that further adjustments are needed, the scope/invasiveness of the patch makes it worthwhile to get merge this now. It's painful to maintain externally, too complicated to commit after the code code freeze, and a dependency of a number of other patches. Catversion bump, for obvious reasons. Author: Andres Freund, with contributions by John Naylor Discussion: https://postgr.es/m/20180930034810.ywp2c7awz7opzcfr@alap3.anarazel.de
2018-11-21 00:36:57 +01:00
ofTypeId = ((Form_pg_type) GETSTRUCT(tuple))->oid;
ofTypename->typeOid = ofTypeId; /* cached for later */
tupdesc = lookup_rowtype_tupdesc(ofTypeId, -1);
for (i = 0; i < tupdesc->natts; i++)
{
Form_pg_attribute attr = TupleDescAttr(tupdesc, i);
Remove collation information from TypeName, where it does not belong. The initial collations patch treated a COLLATE spec as part of a TypeName, following what can only be described as brain fade on the part of the SQL committee. It's a lot more reasonable to treat COLLATE as a syntactically separate object, so that it can be added in only the productions where it actually belongs, rather than needing to reject it in a boatload of places where it doesn't belong (something the original patch mostly failed to do). In addition this change lets us meet the spec's requirement to allow COLLATE anywhere in the clauses of a ColumnDef, and it avoids unfriendly behavior for constructs such as "foo::type COLLATE collation". To do this, pull collation information out of TypeName and put it in ColumnDef instead, thus reverting most of the collation-related changes in parse_type.c's API. I made one additional structural change, which was to use a ColumnDef as an intermediate node in AT_AlterColumnType AlterTableCmd nodes. This provides enough room to get rid of the "transform" wart in AlterTableCmd too, since the ColumnDef can carry the USING expression easily enough. Also fix some other minor bugs that have crept in in the same areas, like failure to copy recently-added fields of ColumnDef in copyfuncs.c. While at it, document the formerly secret ability to specify a collation in ALTER TABLE ALTER COLUMN TYPE, ALTER TYPE ADD ATTRIBUTE, and ALTER TYPE ALTER ATTRIBUTE TYPE; and correct some misstatements about what the default collation selection will be when COLLATE is omitted. BTW, the three-parameter form of format_type() should go away too, since it just contributes to the confusion in this area; but I'll do that in a separate patch.
2011-03-10 04:38:52 +01:00
ColumnDef *n;
if (attr->attisdropped)
continue;
Remove collation information from TypeName, where it does not belong. The initial collations patch treated a COLLATE spec as part of a TypeName, following what can only be described as brain fade on the part of the SQL committee. It's a lot more reasonable to treat COLLATE as a syntactically separate object, so that it can be added in only the productions where it actually belongs, rather than needing to reject it in a boatload of places where it doesn't belong (something the original patch mostly failed to do). In addition this change lets us meet the spec's requirement to allow COLLATE anywhere in the clauses of a ColumnDef, and it avoids unfriendly behavior for constructs such as "foo::type COLLATE collation". To do this, pull collation information out of TypeName and put it in ColumnDef instead, thus reverting most of the collation-related changes in parse_type.c's API. I made one additional structural change, which was to use a ColumnDef as an intermediate node in AT_AlterColumnType AlterTableCmd nodes. This provides enough room to get rid of the "transform" wart in AlterTableCmd too, since the ColumnDef can carry the USING expression easily enough. Also fix some other minor bugs that have crept in in the same areas, like failure to copy recently-added fields of ColumnDef in copyfuncs.c. While at it, document the formerly secret ability to specify a collation in ALTER TABLE ALTER COLUMN TYPE, ALTER TYPE ADD ATTRIBUTE, and ALTER TYPE ALTER ATTRIBUTE TYPE; and correct some misstatements about what the default collation selection will be when COLLATE is omitted. BTW, the three-parameter form of format_type() should go away too, since it just contributes to the confusion in this area; but I'll do that in a separate patch.
2011-03-10 04:38:52 +01:00
n = makeNode(ColumnDef);
n->colname = pstrdup(NameStr(attr->attname));
Remove collation information from TypeName, where it does not belong. The initial collations patch treated a COLLATE spec as part of a TypeName, following what can only be described as brain fade on the part of the SQL committee. It's a lot more reasonable to treat COLLATE as a syntactically separate object, so that it can be added in only the productions where it actually belongs, rather than needing to reject it in a boatload of places where it doesn't belong (something the original patch mostly failed to do). In addition this change lets us meet the spec's requirement to allow COLLATE anywhere in the clauses of a ColumnDef, and it avoids unfriendly behavior for constructs such as "foo::type COLLATE collation". To do this, pull collation information out of TypeName and put it in ColumnDef instead, thus reverting most of the collation-related changes in parse_type.c's API. I made one additional structural change, which was to use a ColumnDef as an intermediate node in AT_AlterColumnType AlterTableCmd nodes. This provides enough room to get rid of the "transform" wart in AlterTableCmd too, since the ColumnDef can carry the USING expression easily enough. Also fix some other minor bugs that have crept in in the same areas, like failure to copy recently-added fields of ColumnDef in copyfuncs.c. While at it, document the formerly secret ability to specify a collation in ALTER TABLE ALTER COLUMN TYPE, ALTER TYPE ADD ATTRIBUTE, and ALTER TYPE ALTER ATTRIBUTE TYPE; and correct some misstatements about what the default collation selection will be when COLLATE is omitted. BTW, the three-parameter form of format_type() should go away too, since it just contributes to the confusion in this area; but I'll do that in a separate patch.
2011-03-10 04:38:52 +01:00
n->typeName = makeTypeNameFromOid(attr->atttypid, attr->atttypmod);
n->inhcount = 0;
n->is_local = true;
Remove collation information from TypeName, where it does not belong. The initial collations patch treated a COLLATE spec as part of a TypeName, following what can only be described as brain fade on the part of the SQL committee. It's a lot more reasonable to treat COLLATE as a syntactically separate object, so that it can be added in only the productions where it actually belongs, rather than needing to reject it in a boatload of places where it doesn't belong (something the original patch mostly failed to do). In addition this change lets us meet the spec's requirement to allow COLLATE anywhere in the clauses of a ColumnDef, and it avoids unfriendly behavior for constructs such as "foo::type COLLATE collation". To do this, pull collation information out of TypeName and put it in ColumnDef instead, thus reverting most of the collation-related changes in parse_type.c's API. I made one additional structural change, which was to use a ColumnDef as an intermediate node in AT_AlterColumnType AlterTableCmd nodes. This provides enough room to get rid of the "transform" wart in AlterTableCmd too, since the ColumnDef can carry the USING expression easily enough. Also fix some other minor bugs that have crept in in the same areas, like failure to copy recently-added fields of ColumnDef in copyfuncs.c. While at it, document the formerly secret ability to specify a collation in ALTER TABLE ALTER COLUMN TYPE, ALTER TYPE ADD ATTRIBUTE, and ALTER TYPE ALTER ATTRIBUTE TYPE; and correct some misstatements about what the default collation selection will be when COLLATE is omitted. BTW, the three-parameter form of format_type() should go away too, since it just contributes to the confusion in this area; but I'll do that in a separate patch.
2011-03-10 04:38:52 +01:00
n->is_not_null = false;
n->is_from_type = true;
Remove collation information from TypeName, where it does not belong. The initial collations patch treated a COLLATE spec as part of a TypeName, following what can only be described as brain fade on the part of the SQL committee. It's a lot more reasonable to treat COLLATE as a syntactically separate object, so that it can be added in only the productions where it actually belongs, rather than needing to reject it in a boatload of places where it doesn't belong (something the original patch mostly failed to do). In addition this change lets us meet the spec's requirement to allow COLLATE anywhere in the clauses of a ColumnDef, and it avoids unfriendly behavior for constructs such as "foo::type COLLATE collation". To do this, pull collation information out of TypeName and put it in ColumnDef instead, thus reverting most of the collation-related changes in parse_type.c's API. I made one additional structural change, which was to use a ColumnDef as an intermediate node in AT_AlterColumnType AlterTableCmd nodes. This provides enough room to get rid of the "transform" wart in AlterTableCmd too, since the ColumnDef can carry the USING expression easily enough. Also fix some other minor bugs that have crept in in the same areas, like failure to copy recently-added fields of ColumnDef in copyfuncs.c. While at it, document the formerly secret ability to specify a collation in ALTER TABLE ALTER COLUMN TYPE, ALTER TYPE ADD ATTRIBUTE, and ALTER TYPE ALTER ATTRIBUTE TYPE; and correct some misstatements about what the default collation selection will be when COLLATE is omitted. BTW, the three-parameter form of format_type() should go away too, since it just contributes to the confusion in this area; but I'll do that in a separate patch.
2011-03-10 04:38:52 +01:00
n->storage = 0;
n->raw_default = NULL;
n->cooked_default = NULL;
n->collClause = NULL;
n->collOid = attr->attcollation;
n->constraints = NIL;
n->location = -1;
cxt->columns = lappend(cxt->columns, n);
}
ReleaseTupleDesc(tupdesc);
ReleaseSysCache(tuple);
}
/*
* Generate an IndexStmt node using information from an already existing index
Avoid order-of-execution problems with ALTER TABLE ADD PRIMARY KEY. Up to now, DefineIndex() was responsible for adding attnotnull constraints to the columns of a primary key, in any case where it hadn't been convenient for transformIndexConstraint() to mark those columns as is_not_null. It (or rather its minion index_check_primary_key) did this by executing an ALTER TABLE SET NOT NULL command for the target table. The trouble with this solution is that if we're creating the index due to ALTER TABLE ADD PRIMARY KEY, and the outer ALTER TABLE has additional sub-commands, the inner ALTER TABLE's operations executed at the wrong time with respect to the outer ALTER TABLE's operations. In particular, the inner ALTER would perform a validation scan at a point where the table's storage might be inconsistent with its catalog entries. (This is on the hairy edge of being a security problem, but AFAICS it isn't one because the inner scan would only be interested in the tuples' null bitmaps.) This can result in unexpected failures, such as the one seen in bug #15580 from Allison Kaptur. To fix, let's remove the attempt to do SET NOT NULL from DefineIndex(), reducing index_check_primary_key's role to verifying that the columns are already not null. (It shouldn't ever see such a case, but it seems wise to keep the check for safety.) Instead, make transformIndexConstraint() generate ALTER TABLE SET NOT NULL subcommands to be executed ahead of the ADD PRIMARY KEY operation in every case where it can't force the column to be created already-not-null. This requires only minor surgery in parse_utilcmd.c, and it makes for a much more satisfying spec for transformIndexConstraint(): it's no longer having to take it on faith that someone else will handle addition of NOT NULL constraints. To make that work, we have to move the execution of AT_SetNotNull into an ALTER pass that executes ahead of AT_PASS_ADD_INDEX. I moved it to AT_PASS_COL_ATTRS, and put that after AT_PASS_ADD_COL to avoid failure when the column is being added in the same command. This incidentally fixes a bug in the only previous usage of AT_PASS_COL_ATTRS, for AT_SetIdentity: it didn't work either for a newly-added column. Playing around with this exposed a separate bug in ALTER TABLE ONLY ... ADD PRIMARY KEY for partitioned tables. The intent of the ONLY modifier in that context is to prevent doing anything that would require holding lock for a long time --- but the implied SET NOT NULL would recurse to the child partitions, and do an expensive validation scan for any child where the column(s) were not already NOT NULL. To fix that, invent a new ALTER subcommand AT_CheckNotNull that just insists that a child column be already NOT NULL, and apply that, not AT_SetNotNull, when recursing to children in this scenario. This results in a slightly laxer definition of ALTER TABLE ONLY ... SET NOT NULL for partitioned tables, too: that command will now work as long as all children are already NOT NULL, whereas before it just threw up its hands if there were any partitions. In passing, clean up the API of generateClonedIndexStmt(): remove a useless argument, ensure that the output argument is not left undefined, update the header comment. A small side effect of this change is that no-such-column errors in ALTER TABLE ADD PRIMARY KEY now produce a different message that includes the table name, because they are now detected by the SET NOT NULL step which has historically worded its error that way. That seems fine to me, so I didn't make any effort to avoid the wording change. The basic bug #15580 is of very long standing, and these other bugs aren't new in v12 either. However, this is a pretty significant change in the way ALTER TABLE ADD PRIMARY KEY works. On balance it seems best not to back-patch, at least not till we get some more confidence that this patch has no new bugs. Patch by me, but thanks to Jie Zhang for a preliminary version. Discussion: https://postgr.es/m/15580-d1a6de5a3d65da51@postgresql.org Discussion: https://postgr.es/m/1396E95157071C4EBBA51892C5368521017F2E6E63@G08CNEXMBPEKD02.g08.fujitsu.local
2019-04-23 18:25:27 +02:00
* "source_idx".
*
Avoid order-of-execution problems with ALTER TABLE ADD PRIMARY KEY. Up to now, DefineIndex() was responsible for adding attnotnull constraints to the columns of a primary key, in any case where it hadn't been convenient for transformIndexConstraint() to mark those columns as is_not_null. It (or rather its minion index_check_primary_key) did this by executing an ALTER TABLE SET NOT NULL command for the target table. The trouble with this solution is that if we're creating the index due to ALTER TABLE ADD PRIMARY KEY, and the outer ALTER TABLE has additional sub-commands, the inner ALTER TABLE's operations executed at the wrong time with respect to the outer ALTER TABLE's operations. In particular, the inner ALTER would perform a validation scan at a point where the table's storage might be inconsistent with its catalog entries. (This is on the hairy edge of being a security problem, but AFAICS it isn't one because the inner scan would only be interested in the tuples' null bitmaps.) This can result in unexpected failures, such as the one seen in bug #15580 from Allison Kaptur. To fix, let's remove the attempt to do SET NOT NULL from DefineIndex(), reducing index_check_primary_key's role to verifying that the columns are already not null. (It shouldn't ever see such a case, but it seems wise to keep the check for safety.) Instead, make transformIndexConstraint() generate ALTER TABLE SET NOT NULL subcommands to be executed ahead of the ADD PRIMARY KEY operation in every case where it can't force the column to be created already-not-null. This requires only minor surgery in parse_utilcmd.c, and it makes for a much more satisfying spec for transformIndexConstraint(): it's no longer having to take it on faith that someone else will handle addition of NOT NULL constraints. To make that work, we have to move the execution of AT_SetNotNull into an ALTER pass that executes ahead of AT_PASS_ADD_INDEX. I moved it to AT_PASS_COL_ATTRS, and put that after AT_PASS_ADD_COL to avoid failure when the column is being added in the same command. This incidentally fixes a bug in the only previous usage of AT_PASS_COL_ATTRS, for AT_SetIdentity: it didn't work either for a newly-added column. Playing around with this exposed a separate bug in ALTER TABLE ONLY ... ADD PRIMARY KEY for partitioned tables. The intent of the ONLY modifier in that context is to prevent doing anything that would require holding lock for a long time --- but the implied SET NOT NULL would recurse to the child partitions, and do an expensive validation scan for any child where the column(s) were not already NOT NULL. To fix that, invent a new ALTER subcommand AT_CheckNotNull that just insists that a child column be already NOT NULL, and apply that, not AT_SetNotNull, when recursing to children in this scenario. This results in a slightly laxer definition of ALTER TABLE ONLY ... SET NOT NULL for partitioned tables, too: that command will now work as long as all children are already NOT NULL, whereas before it just threw up its hands if there were any partitions. In passing, clean up the API of generateClonedIndexStmt(): remove a useless argument, ensure that the output argument is not left undefined, update the header comment. A small side effect of this change is that no-such-column errors in ALTER TABLE ADD PRIMARY KEY now produce a different message that includes the table name, because they are now detected by the SET NOT NULL step which has historically worded its error that way. That seems fine to me, so I didn't make any effort to avoid the wording change. The basic bug #15580 is of very long standing, and these other bugs aren't new in v12 either. However, this is a pretty significant change in the way ALTER TABLE ADD PRIMARY KEY works. On balance it seems best not to back-patch, at least not till we get some more confidence that this patch has no new bugs. Patch by me, but thanks to Jie Zhang for a preliminary version. Discussion: https://postgr.es/m/15580-d1a6de5a3d65da51@postgresql.org Discussion: https://postgr.es/m/1396E95157071C4EBBA51892C5368521017F2E6E63@G08CNEXMBPEKD02.g08.fujitsu.local
2019-04-23 18:25:27 +02:00
* heapRel is stored into the IndexStmt's relation field, but we don't use it
* otherwise; some callers pass NULL, if they don't need it to be valid.
* (The target relation might not exist yet, so we mustn't try to access it.)
*
* Attribute numbers in expression Vars are adjusted according to attmap.
*
* If constraintOid isn't NULL, we store the OID of any constraint associated
* with the index there.
*
* Unlike transformIndexConstraint, we don't make any effort to force primary
* key columns to be NOT NULL. The larger cloning process this is part of
* should have cloned their NOT NULL status separately (and DefineIndex will
* complain if that fails to happen).
*/
IndexStmt *
Avoid order-of-execution problems with ALTER TABLE ADD PRIMARY KEY. Up to now, DefineIndex() was responsible for adding attnotnull constraints to the columns of a primary key, in any case where it hadn't been convenient for transformIndexConstraint() to mark those columns as is_not_null. It (or rather its minion index_check_primary_key) did this by executing an ALTER TABLE SET NOT NULL command for the target table. The trouble with this solution is that if we're creating the index due to ALTER TABLE ADD PRIMARY KEY, and the outer ALTER TABLE has additional sub-commands, the inner ALTER TABLE's operations executed at the wrong time with respect to the outer ALTER TABLE's operations. In particular, the inner ALTER would perform a validation scan at a point where the table's storage might be inconsistent with its catalog entries. (This is on the hairy edge of being a security problem, but AFAICS it isn't one because the inner scan would only be interested in the tuples' null bitmaps.) This can result in unexpected failures, such as the one seen in bug #15580 from Allison Kaptur. To fix, let's remove the attempt to do SET NOT NULL from DefineIndex(), reducing index_check_primary_key's role to verifying that the columns are already not null. (It shouldn't ever see such a case, but it seems wise to keep the check for safety.) Instead, make transformIndexConstraint() generate ALTER TABLE SET NOT NULL subcommands to be executed ahead of the ADD PRIMARY KEY operation in every case where it can't force the column to be created already-not-null. This requires only minor surgery in parse_utilcmd.c, and it makes for a much more satisfying spec for transformIndexConstraint(): it's no longer having to take it on faith that someone else will handle addition of NOT NULL constraints. To make that work, we have to move the execution of AT_SetNotNull into an ALTER pass that executes ahead of AT_PASS_ADD_INDEX. I moved it to AT_PASS_COL_ATTRS, and put that after AT_PASS_ADD_COL to avoid failure when the column is being added in the same command. This incidentally fixes a bug in the only previous usage of AT_PASS_COL_ATTRS, for AT_SetIdentity: it didn't work either for a newly-added column. Playing around with this exposed a separate bug in ALTER TABLE ONLY ... ADD PRIMARY KEY for partitioned tables. The intent of the ONLY modifier in that context is to prevent doing anything that would require holding lock for a long time --- but the implied SET NOT NULL would recurse to the child partitions, and do an expensive validation scan for any child where the column(s) were not already NOT NULL. To fix that, invent a new ALTER subcommand AT_CheckNotNull that just insists that a child column be already NOT NULL, and apply that, not AT_SetNotNull, when recursing to children in this scenario. This results in a slightly laxer definition of ALTER TABLE ONLY ... SET NOT NULL for partitioned tables, too: that command will now work as long as all children are already NOT NULL, whereas before it just threw up its hands if there were any partitions. In passing, clean up the API of generateClonedIndexStmt(): remove a useless argument, ensure that the output argument is not left undefined, update the header comment. A small side effect of this change is that no-such-column errors in ALTER TABLE ADD PRIMARY KEY now produce a different message that includes the table name, because they are now detected by the SET NOT NULL step which has historically worded its error that way. That seems fine to me, so I didn't make any effort to avoid the wording change. The basic bug #15580 is of very long standing, and these other bugs aren't new in v12 either. However, this is a pretty significant change in the way ALTER TABLE ADD PRIMARY KEY works. On balance it seems best not to back-patch, at least not till we get some more confidence that this patch has no new bugs. Patch by me, but thanks to Jie Zhang for a preliminary version. Discussion: https://postgr.es/m/15580-d1a6de5a3d65da51@postgresql.org Discussion: https://postgr.es/m/1396E95157071C4EBBA51892C5368521017F2E6E63@G08CNEXMBPEKD02.g08.fujitsu.local
2019-04-23 18:25:27 +02:00
generateClonedIndexStmt(RangeVar *heapRel, Relation source_idx,
const AttrMap *attmap,
Avoid order-of-execution problems with ALTER TABLE ADD PRIMARY KEY. Up to now, DefineIndex() was responsible for adding attnotnull constraints to the columns of a primary key, in any case where it hadn't been convenient for transformIndexConstraint() to mark those columns as is_not_null. It (or rather its minion index_check_primary_key) did this by executing an ALTER TABLE SET NOT NULL command for the target table. The trouble with this solution is that if we're creating the index due to ALTER TABLE ADD PRIMARY KEY, and the outer ALTER TABLE has additional sub-commands, the inner ALTER TABLE's operations executed at the wrong time with respect to the outer ALTER TABLE's operations. In particular, the inner ALTER would perform a validation scan at a point where the table's storage might be inconsistent with its catalog entries. (This is on the hairy edge of being a security problem, but AFAICS it isn't one because the inner scan would only be interested in the tuples' null bitmaps.) This can result in unexpected failures, such as the one seen in bug #15580 from Allison Kaptur. To fix, let's remove the attempt to do SET NOT NULL from DefineIndex(), reducing index_check_primary_key's role to verifying that the columns are already not null. (It shouldn't ever see such a case, but it seems wise to keep the check for safety.) Instead, make transformIndexConstraint() generate ALTER TABLE SET NOT NULL subcommands to be executed ahead of the ADD PRIMARY KEY operation in every case where it can't force the column to be created already-not-null. This requires only minor surgery in parse_utilcmd.c, and it makes for a much more satisfying spec for transformIndexConstraint(): it's no longer having to take it on faith that someone else will handle addition of NOT NULL constraints. To make that work, we have to move the execution of AT_SetNotNull into an ALTER pass that executes ahead of AT_PASS_ADD_INDEX. I moved it to AT_PASS_COL_ATTRS, and put that after AT_PASS_ADD_COL to avoid failure when the column is being added in the same command. This incidentally fixes a bug in the only previous usage of AT_PASS_COL_ATTRS, for AT_SetIdentity: it didn't work either for a newly-added column. Playing around with this exposed a separate bug in ALTER TABLE ONLY ... ADD PRIMARY KEY for partitioned tables. The intent of the ONLY modifier in that context is to prevent doing anything that would require holding lock for a long time --- but the implied SET NOT NULL would recurse to the child partitions, and do an expensive validation scan for any child where the column(s) were not already NOT NULL. To fix that, invent a new ALTER subcommand AT_CheckNotNull that just insists that a child column be already NOT NULL, and apply that, not AT_SetNotNull, when recursing to children in this scenario. This results in a slightly laxer definition of ALTER TABLE ONLY ... SET NOT NULL for partitioned tables, too: that command will now work as long as all children are already NOT NULL, whereas before it just threw up its hands if there were any partitions. In passing, clean up the API of generateClonedIndexStmt(): remove a useless argument, ensure that the output argument is not left undefined, update the header comment. A small side effect of this change is that no-such-column errors in ALTER TABLE ADD PRIMARY KEY now produce a different message that includes the table name, because they are now detected by the SET NOT NULL step which has historically worded its error that way. That seems fine to me, so I didn't make any effort to avoid the wording change. The basic bug #15580 is of very long standing, and these other bugs aren't new in v12 either. However, this is a pretty significant change in the way ALTER TABLE ADD PRIMARY KEY works. On balance it seems best not to back-patch, at least not till we get some more confidence that this patch has no new bugs. Patch by me, but thanks to Jie Zhang for a preliminary version. Discussion: https://postgr.es/m/15580-d1a6de5a3d65da51@postgresql.org Discussion: https://postgr.es/m/1396E95157071C4EBBA51892C5368521017F2E6E63@G08CNEXMBPEKD02.g08.fujitsu.local
2019-04-23 18:25:27 +02:00
Oid *constraintOid)
{
Oid source_relid = RelationGetRelid(source_idx);
HeapTuple ht_idxrel;
HeapTuple ht_idx;
HeapTuple ht_am;
Form_pg_class idxrelrec;
Form_pg_index idxrec;
Form_pg_am amrec;
oidvector *indcollation;
oidvector *indclass;
IndexStmt *index;
List *indexprs;
ListCell *indexpr_item;
Oid indrelid;
int keyno;
Oid keycoltype;
Datum datum;
bool isnull;
Avoid order-of-execution problems with ALTER TABLE ADD PRIMARY KEY. Up to now, DefineIndex() was responsible for adding attnotnull constraints to the columns of a primary key, in any case where it hadn't been convenient for transformIndexConstraint() to mark those columns as is_not_null. It (or rather its minion index_check_primary_key) did this by executing an ALTER TABLE SET NOT NULL command for the target table. The trouble with this solution is that if we're creating the index due to ALTER TABLE ADD PRIMARY KEY, and the outer ALTER TABLE has additional sub-commands, the inner ALTER TABLE's operations executed at the wrong time with respect to the outer ALTER TABLE's operations. In particular, the inner ALTER would perform a validation scan at a point where the table's storage might be inconsistent with its catalog entries. (This is on the hairy edge of being a security problem, but AFAICS it isn't one because the inner scan would only be interested in the tuples' null bitmaps.) This can result in unexpected failures, such as the one seen in bug #15580 from Allison Kaptur. To fix, let's remove the attempt to do SET NOT NULL from DefineIndex(), reducing index_check_primary_key's role to verifying that the columns are already not null. (It shouldn't ever see such a case, but it seems wise to keep the check for safety.) Instead, make transformIndexConstraint() generate ALTER TABLE SET NOT NULL subcommands to be executed ahead of the ADD PRIMARY KEY operation in every case where it can't force the column to be created already-not-null. This requires only minor surgery in parse_utilcmd.c, and it makes for a much more satisfying spec for transformIndexConstraint(): it's no longer having to take it on faith that someone else will handle addition of NOT NULL constraints. To make that work, we have to move the execution of AT_SetNotNull into an ALTER pass that executes ahead of AT_PASS_ADD_INDEX. I moved it to AT_PASS_COL_ATTRS, and put that after AT_PASS_ADD_COL to avoid failure when the column is being added in the same command. This incidentally fixes a bug in the only previous usage of AT_PASS_COL_ATTRS, for AT_SetIdentity: it didn't work either for a newly-added column. Playing around with this exposed a separate bug in ALTER TABLE ONLY ... ADD PRIMARY KEY for partitioned tables. The intent of the ONLY modifier in that context is to prevent doing anything that would require holding lock for a long time --- but the implied SET NOT NULL would recurse to the child partitions, and do an expensive validation scan for any child where the column(s) were not already NOT NULL. To fix that, invent a new ALTER subcommand AT_CheckNotNull that just insists that a child column be already NOT NULL, and apply that, not AT_SetNotNull, when recursing to children in this scenario. This results in a slightly laxer definition of ALTER TABLE ONLY ... SET NOT NULL for partitioned tables, too: that command will now work as long as all children are already NOT NULL, whereas before it just threw up its hands if there were any partitions. In passing, clean up the API of generateClonedIndexStmt(): remove a useless argument, ensure that the output argument is not left undefined, update the header comment. A small side effect of this change is that no-such-column errors in ALTER TABLE ADD PRIMARY KEY now produce a different message that includes the table name, because they are now detected by the SET NOT NULL step which has historically worded its error that way. That seems fine to me, so I didn't make any effort to avoid the wording change. The basic bug #15580 is of very long standing, and these other bugs aren't new in v12 either. However, this is a pretty significant change in the way ALTER TABLE ADD PRIMARY KEY works. On balance it seems best not to back-patch, at least not till we get some more confidence that this patch has no new bugs. Patch by me, but thanks to Jie Zhang for a preliminary version. Discussion: https://postgr.es/m/15580-d1a6de5a3d65da51@postgresql.org Discussion: https://postgr.es/m/1396E95157071C4EBBA51892C5368521017F2E6E63@G08CNEXMBPEKD02.g08.fujitsu.local
2019-04-23 18:25:27 +02:00
if (constraintOid)
*constraintOid = InvalidOid;
/*
* Fetch pg_class tuple of source index. We can't use the copy in the
* relcache entry because it doesn't include optional fields.
*/
ht_idxrel = SearchSysCache1(RELOID, ObjectIdGetDatum(source_relid));
if (!HeapTupleIsValid(ht_idxrel))
elog(ERROR, "cache lookup failed for relation %u", source_relid);
idxrelrec = (Form_pg_class) GETSTRUCT(ht_idxrel);
/* Fetch pg_index tuple for source index from relcache entry */
ht_idx = source_idx->rd_indextuple;
idxrec = (Form_pg_index) GETSTRUCT(ht_idx);
indrelid = idxrec->indrelid;
/* Fetch the pg_am tuple of the index' access method */
ht_am = SearchSysCache1(AMOID, ObjectIdGetDatum(idxrelrec->relam));
if (!HeapTupleIsValid(ht_am))
elog(ERROR, "cache lookup failed for access method %u",
idxrelrec->relam);
amrec = (Form_pg_am) GETSTRUCT(ht_am);
/* Extract indcollation from the pg_index tuple */
datum = SysCacheGetAttrNotNull(INDEXRELID, ht_idx,
Anum_pg_index_indcollation);
indcollation = (oidvector *) DatumGetPointer(datum);
/* Extract indclass from the pg_index tuple */
datum = SysCacheGetAttrNotNull(INDEXRELID, ht_idx, Anum_pg_index_indclass);
indclass = (oidvector *) DatumGetPointer(datum);
/* Begin building the IndexStmt */
index = makeNode(IndexStmt);
index->relation = heapRel;
index->accessMethod = pstrdup(NameStr(amrec->amname));
if (OidIsValid(idxrelrec->reltablespace))
index->tableSpace = get_tablespace_name(idxrelrec->reltablespace);
else
index->tableSpace = NULL;
index->excludeOpNames = NIL;
index->idxcomment = NULL;
index->indexOid = InvalidOid;
Change internal RelFileNode references to RelFileNumber or RelFileLocator. We have been using the term RelFileNode to refer to either (1) the integer that is used to name the sequence of files for a certain relation within the directory set aside for that tablespace/database combination; or (2) that value plus the OIDs of the tablespace and database; or occasionally (3) the whole series of files created for a relation based on those values. Using the same name for more than one thing is confusing. Replace RelFileNode with RelFileNumber when we're talking about just the single number, i.e. (1) from above, and with RelFileLocator when we're talking about all the things that are needed to locate a relation's files on disk, i.e. (2) from above. In the places where we refer to (3) as a relfilenode, instead refer to "relation storage". Since there is a ton of SQL code in the world that knows about pg_class.relfilenode, don't change the name of that column, or of other SQL-facing things that derive their name from it. On the other hand, do adjust closely-related internal terminology. For example, the structure member names dbNode and spcNode appear to be derived from the fact that the structure itself was called RelFileNode, so change those to dbOid and spcOid. Likewise, various variables with names like rnode and relnode get renamed appropriately, according to how they're being used in context. Hopefully, this is clearer than before. It is also preparation for future patches that intend to widen the relfilenumber fields from its current width of 32 bits. Variables that store a relfilenumber are now declared as type RelFileNumber rather than type Oid; right now, these are the same, but that can now more easily be changed. Dilip Kumar, per an idea from me. Reviewed also by Andres Freund. I fixed some whitespace issues, changed a couple of words in a comment, and made one other minor correction. Discussion: http://postgr.es/m/CA+TgmoamOtXbVAQf9hWFzonUo6bhhjS6toZQd7HZ-pmojtAmag@mail.gmail.com Discussion: http://postgr.es/m/CA+Tgmobp7+7kmi4gkq7Y+4AM9fTvL+O1oQ4-5gFTT+6Ng-dQ=g@mail.gmail.com Discussion: http://postgr.es/m/CAFiTN-vTe79M8uDH1yprOU64MNFE+R3ODRuA+JWf27JbhY4hJw@mail.gmail.com
2022-07-06 17:39:09 +02:00
index->oldNumber = InvalidRelFileNumber;
Skip WAL for new relfilenodes, under wal_level=minimal. Until now, only selected bulk operations (e.g. COPY) did this. If a given relfilenode received both a WAL-skipping COPY and a WAL-logged operation (e.g. INSERT), recovery could lose tuples from the COPY. See src/backend/access/transam/README section "Skipping WAL for New RelFileNode" for the new coding rules. Maintainers of table access methods should examine that section. To maintain data durability, just before commit, we choose between an fsync of the relfilenode and copying its contents to WAL. A new GUC, wal_skip_threshold, guides that choice. If this change slows a workload that creates small, permanent relfilenodes under wal_level=minimal, try adjusting wal_skip_threshold. Users setting a timeout on COMMIT may need to adjust that timeout, and log_min_duration_statement analysis will reflect time consumption moving to COMMIT from commands like COPY. Internally, this requires a reliable determination of whether RollbackAndReleaseCurrentSubTransaction() would unlink a relation's current relfilenode. Introduce rd_firstRelfilenodeSubid. Amend the specification of rd_createSubid such that the field is zero when a new rel has an old rd_node. Make relcache.c retain entries for certain dropped relations until end of transaction. Bump XLOG_PAGE_MAGIC, since this introduces XLOG_GIST_ASSIGN_LSN. Future servers accept older WAL, so this bump is discretionary. Kyotaro Horiguchi, reviewed (in earlier, similar versions) by Robert Haas. Heikki Linnakangas and Michael Paquier implemented earlier designs that materially clarified the problem. Reviewed, in earlier designs, by Andrew Dunstan, Andres Freund, Alvaro Herrera, Tom Lane, Fujii Masao, and Simon Riggs. Reported by Martijn van Oosterhout. Discussion: https://postgr.es/m/20150702220524.GA9392@svana.org
2020-04-04 21:25:34 +02:00
index->oldCreateSubid = InvalidSubTransactionId;
Change internal RelFileNode references to RelFileNumber or RelFileLocator. We have been using the term RelFileNode to refer to either (1) the integer that is used to name the sequence of files for a certain relation within the directory set aside for that tablespace/database combination; or (2) that value plus the OIDs of the tablespace and database; or occasionally (3) the whole series of files created for a relation based on those values. Using the same name for more than one thing is confusing. Replace RelFileNode with RelFileNumber when we're talking about just the single number, i.e. (1) from above, and with RelFileLocator when we're talking about all the things that are needed to locate a relation's files on disk, i.e. (2) from above. In the places where we refer to (3) as a relfilenode, instead refer to "relation storage". Since there is a ton of SQL code in the world that knows about pg_class.relfilenode, don't change the name of that column, or of other SQL-facing things that derive their name from it. On the other hand, do adjust closely-related internal terminology. For example, the structure member names dbNode and spcNode appear to be derived from the fact that the structure itself was called RelFileNode, so change those to dbOid and spcOid. Likewise, various variables with names like rnode and relnode get renamed appropriately, according to how they're being used in context. Hopefully, this is clearer than before. It is also preparation for future patches that intend to widen the relfilenumber fields from its current width of 32 bits. Variables that store a relfilenumber are now declared as type RelFileNumber rather than type Oid; right now, these are the same, but that can now more easily be changed. Dilip Kumar, per an idea from me. Reviewed also by Andres Freund. I fixed some whitespace issues, changed a couple of words in a comment, and made one other minor correction. Discussion: http://postgr.es/m/CA+TgmoamOtXbVAQf9hWFzonUo6bhhjS6toZQd7HZ-pmojtAmag@mail.gmail.com Discussion: http://postgr.es/m/CA+Tgmobp7+7kmi4gkq7Y+4AM9fTvL+O1oQ4-5gFTT+6Ng-dQ=g@mail.gmail.com Discussion: http://postgr.es/m/CAFiTN-vTe79M8uDH1yprOU64MNFE+R3ODRuA+JWf27JbhY4hJw@mail.gmail.com
2022-07-06 17:39:09 +02:00
index->oldFirstRelfilelocatorSubid = InvalidSubTransactionId;
index->unique = idxrec->indisunique;
index->nulls_not_distinct = idxrec->indnullsnotdistinct;
index->primary = idxrec->indisprimary;
Get rid of multiple applications of transformExpr() to the same tree. transformExpr() has for many years had provisions to do nothing when applied to an already-transformed expression tree. However, this was always ugly and of dubious reliability, so we'd be much better off without it. The primary historical reason for it was that gram.y sometimes returned multiple links to the same subexpression, which is no longer true as of my BETWEEN fixes. We'd also grown some lazy hacks in CREATE TABLE LIKE (failing to distinguish between raw and already-transformed index specifications) and one or two other places. This patch removes the need for and support for re-transforming already transformed expressions. The index case is dealt with by adding a flag to struct IndexStmt to indicate that it's already been transformed; which has some benefit anyway in that tablecmds.c can now Assert that transformation has happened rather than just assuming. The other main reason was some rather sloppy code for array type coercion, which can be fixed (and its performance improved too) by refactoring. I did leave transformJoinUsingClause() still constructing expressions containing untransformed operator nodes being applied to Vars, so that transformExpr() still has to allow Var inputs. But that's a much narrower, and safer, special case than before, since Vars will never appear in a raw parse tree, and they don't have any substructure to worry about. In passing fix some oversights in the patch that added CREATE INDEX IF NOT EXISTS (missing processing of IndexStmt.if_not_exists). These appear relatively harmless, but still sloppy coding practice.
2015-02-22 19:59:09 +01:00
index->transformed = true; /* don't need transformIndexStmt */
index->concurrent = false;
Get rid of multiple applications of transformExpr() to the same tree. transformExpr() has for many years had provisions to do nothing when applied to an already-transformed expression tree. However, this was always ugly and of dubious reliability, so we'd be much better off without it. The primary historical reason for it was that gram.y sometimes returned multiple links to the same subexpression, which is no longer true as of my BETWEEN fixes. We'd also grown some lazy hacks in CREATE TABLE LIKE (failing to distinguish between raw and already-transformed index specifications) and one or two other places. This patch removes the need for and support for re-transforming already transformed expressions. The index case is dealt with by adding a flag to struct IndexStmt to indicate that it's already been transformed; which has some benefit anyway in that tablecmds.c can now Assert that transformation has happened rather than just assuming. The other main reason was some rather sloppy code for array type coercion, which can be fixed (and its performance improved too) by refactoring. I did leave transformJoinUsingClause() still constructing expressions containing untransformed operator nodes being applied to Vars, so that transformExpr() still has to allow Var inputs. But that's a much narrower, and safer, special case than before, since Vars will never appear in a raw parse tree, and they don't have any substructure to worry about. In passing fix some oversights in the patch that added CREATE INDEX IF NOT EXISTS (missing processing of IndexStmt.if_not_exists). These appear relatively harmless, but still sloppy coding practice.
2015-02-22 19:59:09 +01:00
index->if_not_exists = false;
index->reset_default_tblspc = false;
/*
* We don't try to preserve the name of the source index; instead, just
* let DefineIndex() choose a reasonable name. (If we tried to preserve
* the name, we'd get duplicate-relation-name failures unless the source
* table was in a different schema.)
*/
index->idxname = NULL;
/*
* If the index is marked PRIMARY or has an exclusion condition, it's
* certainly from a constraint; else, if it's not marked UNIQUE, it
* certainly isn't. If it is or might be from a constraint, we have to
* fetch the pg_constraint record.
*/
if (index->primary || index->unique || idxrec->indisexclusion)
{
Oid constraintId = get_index_constraint(source_relid);
if (OidIsValid(constraintId))
{
HeapTuple ht_constr;
Form_pg_constraint conrec;
if (constraintOid)
*constraintOid = constraintId;
ht_constr = SearchSysCache1(CONSTROID,
ObjectIdGetDatum(constraintId));
if (!HeapTupleIsValid(ht_constr))
elog(ERROR, "cache lookup failed for constraint %u",
constraintId);
conrec = (Form_pg_constraint) GETSTRUCT(ht_constr);
index->isconstraint = true;
index->deferrable = conrec->condeferrable;
index->initdeferred = conrec->condeferred;
/* If it's an exclusion constraint, we need the operator names */
if (idxrec->indisexclusion)
{
Datum *elems;
int nElems;
int i;
Assert(conrec->contype == CONSTRAINT_EXCLUSION);
/* Extract operator OIDs from the pg_constraint tuple */
datum = SysCacheGetAttrNotNull(CONSTROID, ht_constr,
Anum_pg_constraint_conexclop);
deconstruct_array_builtin(DatumGetArrayTypeP(datum), OIDOID, &elems, NULL, &nElems);
for (i = 0; i < nElems; i++)
{
Oid operid = DatumGetObjectId(elems[i]);
HeapTuple opertup;
Form_pg_operator operform;
char *oprname;
char *nspname;
List *namelist;
opertup = SearchSysCache1(OPEROID,
ObjectIdGetDatum(operid));
if (!HeapTupleIsValid(opertup))
elog(ERROR, "cache lookup failed for operator %u",
operid);
operform = (Form_pg_operator) GETSTRUCT(opertup);
oprname = pstrdup(NameStr(operform->oprname));
/* For simplicity we always schema-qualify the op name */
nspname = get_namespace_name(operform->oprnamespace);
namelist = list_make2(makeString(nspname),
makeString(oprname));
index->excludeOpNames = lappend(index->excludeOpNames,
namelist);
ReleaseSysCache(opertup);
}
}
ReleaseSysCache(ht_constr);
}
else
index->isconstraint = false;
}
else
index->isconstraint = false;
/* Get the index expressions, if any */
datum = SysCacheGetAttr(INDEXRELID, ht_idx,
Anum_pg_index_indexprs, &isnull);
if (!isnull)
{
char *exprsString;
exprsString = TextDatumGetCString(datum);
indexprs = (List *) stringToNode(exprsString);
}
else
indexprs = NIL;
/* Build the list of IndexElem */
index->indexParams = NIL;
index->indexIncludingParams = NIL;
indexpr_item = list_head(indexprs);
for (keyno = 0; keyno < idxrec->indnkeyatts; keyno++)
{
IndexElem *iparam;
AttrNumber attnum = idxrec->indkey.values[keyno];
Form_pg_attribute attr = TupleDescAttr(RelationGetDescr(source_idx),
keyno);
int16 opt = source_idx->rd_indoption[keyno];
iparam = makeNode(IndexElem);
if (AttributeNumberIsValid(attnum))
{
/* Simple index column */
char *attname;
attname = get_attname(indrelid, attnum, false);
keycoltype = get_atttype(indrelid, attnum);
iparam->name = attname;
iparam->expr = NULL;
}
else
{
/* Expressional index */
Node *indexkey;
Prevent CREATE TABLE LIKE/INHERITS from (mis) copying whole-row Vars. If a CHECK constraint or index definition contained a whole-row Var (that is, "table.*"), an attempt to copy that definition via CREATE TABLE LIKE or table inheritance produced incorrect results: the copied Var still claimed to have the rowtype of the source table, rather than the created table. For the LIKE case, it seems reasonable to just throw error for this situation, since the point of LIKE is that the new table is not permanently coupled to the old, so there's no reason to assume its rowtype will stay compatible. In the inheritance case, we should ideally allow such constraints, but doing so will require nontrivial refactoring of CREATE TABLE processing (because we'd need to know the OID of the new table's rowtype before we adjust inherited CHECK constraints). In view of the lack of previous complaints, that doesn't seem worth the risk in a back-patched bug fix, so just make it throw error for the inheritance case as well. Along the way, replace change_varattnos_of_a_node() with a more robust function map_variable_attnos(), which is capable of being extended to handle insertion of ConvertRowtypeExpr whenever we get around to fixing the inheritance case nicely, and in the meantime it returns a failure indication to the caller so that a helpful message with some context can be thrown. Also, this code will do the right thing with subselects (if we ever allow them in CHECK or indexes), and it range-checks varattnos before using them to index into the map array. Per report from Sergey Konoplev. Back-patch to all supported branches.
2012-06-30 22:43:50 +02:00
bool found_whole_row;
if (indexpr_item == NULL)
elog(ERROR, "too few entries in indexprs list");
indexkey = (Node *) lfirst(indexpr_item);
Represent Lists as expansible arrays, not chains of cons-cells. Originally, Postgres Lists were a more or less exact reimplementation of Lisp lists, which consist of chains of separately-allocated cons cells, each having a value and a next-cell link. We'd hacked that once before (commit d0b4399d8) to add a separate List header, but the data was still in cons cells. That makes some operations -- notably list_nth() -- O(N), and it's bulky because of the next-cell pointers and per-cell palloc overhead, and it's very cache-unfriendly if the cons cells end up scattered around rather than being adjacent. In this rewrite, we still have List headers, but the data is in a resizable array of values, with no next-cell links. Now we need at most two palloc's per List, and often only one, since we can allocate some values in the same palloc call as the List header. (Of course, extending an existing List may require repalloc's to enlarge the array. But this involves just O(log N) allocations not O(N).) Of course this is not without downsides. The key difficulty is that addition or deletion of a list entry may now cause other entries to move, which it did not before. For example, that breaks foreach() and sister macros, which historically used a pointer to the current cons-cell as loop state. We can repair those macros transparently by making their actual loop state be an integer list index; the exposed "ListCell *" pointer is no longer state carried across loop iterations, but is just a derived value. (In practice, modern compilers can optimize things back to having just one loop state value, at least for simple cases with inline loop bodies.) In principle, this is a semantics change for cases where the loop body inserts or deletes list entries ahead of the current loop index; but I found no such cases in the Postgres code. The change is not at all transparent for code that doesn't use foreach() but chases lists "by hand" using lnext(). The largest share of such code in the backend is in loops that were maintaining "prev" and "next" variables in addition to the current-cell pointer, in order to delete list cells efficiently using list_delete_cell(). However, we no longer need a previous-cell pointer to delete a list cell efficiently. Keeping a next-cell pointer doesn't work, as explained above, but we can improve matters by changing such code to use a regular foreach() loop and then using the new macro foreach_delete_current() to delete the current cell. (This macro knows how to update the associated foreach loop's state so that no cells will be missed in the traversal.) There remains a nontrivial risk of code assuming that a ListCell * pointer will remain good over an operation that could now move the list contents. To help catch such errors, list.c can be compiled with a new define symbol DEBUG_LIST_MEMORY_USAGE that forcibly moves list contents whenever that could possibly happen. This makes list operations significantly more expensive so it's not normally turned on (though it is on by default if USE_VALGRIND is on). There are two notable API differences from the previous code: * lnext() now requires the List's header pointer in addition to the current cell's address. * list_delete_cell() no longer requires a previous-cell argument. These changes are somewhat unfortunate, but on the other hand code using either function needs inspection to see if it is assuming anything it shouldn't, so it's not all bad. Programmers should be aware of these significant performance changes: * list_nth() and related functions are now O(1); so there's no major access-speed difference between a list and an array. * Inserting or deleting a list element now takes time proportional to the distance to the end of the list, due to moving the array elements. (However, it typically *doesn't* require palloc or pfree, so except in long lists it's probably still faster than before.) Notably, lcons() used to be about the same cost as lappend(), but that's no longer true if the list is long. Code that uses lcons() and list_delete_first() to maintain a stack might usefully be rewritten to push and pop at the end of the list rather than the beginning. * There are now list_insert_nth...() and list_delete_nth...() functions that add or remove a list cell identified by index. These have the data-movement penalty explained above, but there's no search penalty. * list_concat() and variants now copy the second list's data into storage belonging to the first list, so there is no longer any sharing of cells between the input lists. The second argument is now declared "const List *" to reflect that it isn't changed. This patch just does the minimum needed to get the new implementation in place and fix bugs exposed by the regression tests. As suggested by the foregoing, there's a fair amount of followup work remaining to do. Also, the ENABLE_LIST_COMPAT macros are finally removed in this commit. Code using those should have been gone a dozen years ago. Patch by me; thanks to David Rowley, Jesper Pedersen, and others for review. Discussion: https://postgr.es/m/11587.1550975080@sss.pgh.pa.us
2019-07-15 19:41:58 +02:00
indexpr_item = lnext(indexprs, indexpr_item);
Prevent CREATE TABLE LIKE/INHERITS from (mis) copying whole-row Vars. If a CHECK constraint or index definition contained a whole-row Var (that is, "table.*"), an attempt to copy that definition via CREATE TABLE LIKE or table inheritance produced incorrect results: the copied Var still claimed to have the rowtype of the source table, rather than the created table. For the LIKE case, it seems reasonable to just throw error for this situation, since the point of LIKE is that the new table is not permanently coupled to the old, so there's no reason to assume its rowtype will stay compatible. In the inheritance case, we should ideally allow such constraints, but doing so will require nontrivial refactoring of CREATE TABLE processing (because we'd need to know the OID of the new table's rowtype before we adjust inherited CHECK constraints). In view of the lack of previous complaints, that doesn't seem worth the risk in a back-patched bug fix, so just make it throw error for the inheritance case as well. Along the way, replace change_varattnos_of_a_node() with a more robust function map_variable_attnos(), which is capable of being extended to handle insertion of ConvertRowtypeExpr whenever we get around to fixing the inheritance case nicely, and in the meantime it returns a failure indication to the caller so that a helpful message with some context can be thrown. Also, this code will do the right thing with subselects (if we ever allow them in CHECK or indexes), and it range-checks varattnos before using them to index into the map array. Per report from Sergey Konoplev. Back-patch to all supported branches.
2012-06-30 22:43:50 +02:00
/* Adjust Vars to match new table's column numbering */
indexkey = map_variable_attnos(indexkey,
1, 0,
attmap,
InvalidOid, &found_whole_row);
Prevent CREATE TABLE LIKE/INHERITS from (mis) copying whole-row Vars. If a CHECK constraint or index definition contained a whole-row Var (that is, "table.*"), an attempt to copy that definition via CREATE TABLE LIKE or table inheritance produced incorrect results: the copied Var still claimed to have the rowtype of the source table, rather than the created table. For the LIKE case, it seems reasonable to just throw error for this situation, since the point of LIKE is that the new table is not permanently coupled to the old, so there's no reason to assume its rowtype will stay compatible. In the inheritance case, we should ideally allow such constraints, but doing so will require nontrivial refactoring of CREATE TABLE processing (because we'd need to know the OID of the new table's rowtype before we adjust inherited CHECK constraints). In view of the lack of previous complaints, that doesn't seem worth the risk in a back-patched bug fix, so just make it throw error for the inheritance case as well. Along the way, replace change_varattnos_of_a_node() with a more robust function map_variable_attnos(), which is capable of being extended to handle insertion of ConvertRowtypeExpr whenever we get around to fixing the inheritance case nicely, and in the meantime it returns a failure indication to the caller so that a helpful message with some context can be thrown. Also, this code will do the right thing with subselects (if we ever allow them in CHECK or indexes), and it range-checks varattnos before using them to index into the map array. Per report from Sergey Konoplev. Back-patch to all supported branches.
2012-06-30 22:43:50 +02:00
/* As in expandTableLikeClause, reject whole-row variables */
Prevent CREATE TABLE LIKE/INHERITS from (mis) copying whole-row Vars. If a CHECK constraint or index definition contained a whole-row Var (that is, "table.*"), an attempt to copy that definition via CREATE TABLE LIKE or table inheritance produced incorrect results: the copied Var still claimed to have the rowtype of the source table, rather than the created table. For the LIKE case, it seems reasonable to just throw error for this situation, since the point of LIKE is that the new table is not permanently coupled to the old, so there's no reason to assume its rowtype will stay compatible. In the inheritance case, we should ideally allow such constraints, but doing so will require nontrivial refactoring of CREATE TABLE processing (because we'd need to know the OID of the new table's rowtype before we adjust inherited CHECK constraints). In view of the lack of previous complaints, that doesn't seem worth the risk in a back-patched bug fix, so just make it throw error for the inheritance case as well. Along the way, replace change_varattnos_of_a_node() with a more robust function map_variable_attnos(), which is capable of being extended to handle insertion of ConvertRowtypeExpr whenever we get around to fixing the inheritance case nicely, and in the meantime it returns a failure indication to the caller so that a helpful message with some context can be thrown. Also, this code will do the right thing with subselects (if we ever allow them in CHECK or indexes), and it range-checks varattnos before using them to index into the map array. Per report from Sergey Konoplev. Back-patch to all supported branches.
2012-06-30 22:43:50 +02:00
if (found_whole_row)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot convert whole-row table reference"),
errdetail("Index \"%s\" contains a whole-row table reference.",
RelationGetRelationName(source_idx))));
iparam->name = NULL;
iparam->expr = indexkey;
keycoltype = exprType(indexkey);
}
/* Copy the original index column name */
iparam->indexcolname = pstrdup(NameStr(attr->attname));
/* Add the collation name, if non-default */
iparam->collation = get_collation(indcollation->values[keyno], keycoltype);
/* Add the operator class name, if non-default */
iparam->opclass = get_opclass(indclass->values[keyno], keycoltype);
Implement operator class parameters PostgreSQL provides set of template index access methods, where opclasses have much freedom in the semantics of indexing. These index AMs are GiST, GIN, SP-GiST and BRIN. There opclasses define representation of keys, operations on them and supported search strategies. So, it's natural that opclasses may be faced some tradeoffs, which require user-side decision. This commit implements opclass parameters allowing users to set some values, which tell opclass how to index the particular dataset. This commit doesn't introduce new storage in system catalog. Instead it uses pg_attribute.attoptions, which is used for table column storage options but unused for index attributes. In order to evade changing signature of each opclass support function, we implement unified way to pass options to opclass support functions. Options are set to fn_expr as the constant bytea expression. It's possible due to the fact that opclass support functions are executed outside of expressions, so fn_expr is unused for them. This commit comes with some examples of opclass options usage. We parametrize signature length in GiST. That applies to multiple opclasses: tsvector_ops, gist__intbig_ops, gist_ltree_ops, gist__ltree_ops, gist_trgm_ops and gist_hstore_ops. Also we parametrize maximum number of integer ranges for gist__int_ops. However, the main future usage of this feature is expected to be json, where users would be able to specify which way to index particular json parts. Catversion is bumped. Discussion: https://postgr.es/m/d22c3a18-31c7-1879-fc11-4c1ce2f5e5af%40postgrespro.ru Author: Nikita Glukhov, revised by me Reviwed-by: Nikolay Shaplov, Robert Haas, Tom Lane, Tomas Vondra, Alvaro Herrera
2020-03-30 18:17:11 +02:00
iparam->opclassopts =
untransformRelOptions(get_attoptions(source_relid, keyno + 1));
iparam->ordering = SORTBY_DEFAULT;
iparam->nulls_ordering = SORTBY_NULLS_DEFAULT;
/* Adjust options if necessary */
if (source_idx->rd_indam->amcanorder)
{
/*
* If it supports sort ordering, copy DESC and NULLS opts. Don't
* set non-default settings unnecessarily, though, so as to
* improve the chance of recognizing equivalence to constraint
* indexes.
*/
if (opt & INDOPTION_DESC)
{
iparam->ordering = SORTBY_DESC;
if ((opt & INDOPTION_NULLS_FIRST) == 0)
iparam->nulls_ordering = SORTBY_NULLS_LAST;
}
else
{
if (opt & INDOPTION_NULLS_FIRST)
iparam->nulls_ordering = SORTBY_NULLS_FIRST;
}
}
index->indexParams = lappend(index->indexParams, iparam);
}
/* Handle included columns separately */
for (keyno = idxrec->indnkeyatts; keyno < idxrec->indnatts; keyno++)
{
IndexElem *iparam;
AttrNumber attnum = idxrec->indkey.values[keyno];
Form_pg_attribute attr = TupleDescAttr(RelationGetDescr(source_idx),
keyno);
iparam = makeNode(IndexElem);
if (AttributeNumberIsValid(attnum))
{
/* Simple index column */
char *attname;
attname = get_attname(indrelid, attnum, false);
iparam->name = attname;
iparam->expr = NULL;
}
else
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("expressions are not supported in included columns")));
/* Copy the original index column name */
iparam->indexcolname = pstrdup(NameStr(attr->attname));
index->indexIncludingParams = lappend(index->indexIncludingParams, iparam);
}
/* Copy reloptions if any */
datum = SysCacheGetAttr(RELOID, ht_idxrel,
Anum_pg_class_reloptions, &isnull);
if (!isnull)
index->options = untransformRelOptions(datum);
/* If it's a partial index, decompile and append the predicate */
datum = SysCacheGetAttr(INDEXRELID, ht_idx,
Anum_pg_index_indpred, &isnull);
if (!isnull)
{
char *pred_str;
Prevent CREATE TABLE LIKE/INHERITS from (mis) copying whole-row Vars. If a CHECK constraint or index definition contained a whole-row Var (that is, "table.*"), an attempt to copy that definition via CREATE TABLE LIKE or table inheritance produced incorrect results: the copied Var still claimed to have the rowtype of the source table, rather than the created table. For the LIKE case, it seems reasonable to just throw error for this situation, since the point of LIKE is that the new table is not permanently coupled to the old, so there's no reason to assume its rowtype will stay compatible. In the inheritance case, we should ideally allow such constraints, but doing so will require nontrivial refactoring of CREATE TABLE processing (because we'd need to know the OID of the new table's rowtype before we adjust inherited CHECK constraints). In view of the lack of previous complaints, that doesn't seem worth the risk in a back-patched bug fix, so just make it throw error for the inheritance case as well. Along the way, replace change_varattnos_of_a_node() with a more robust function map_variable_attnos(), which is capable of being extended to handle insertion of ConvertRowtypeExpr whenever we get around to fixing the inheritance case nicely, and in the meantime it returns a failure indication to the caller so that a helpful message with some context can be thrown. Also, this code will do the right thing with subselects (if we ever allow them in CHECK or indexes), and it range-checks varattnos before using them to index into the map array. Per report from Sergey Konoplev. Back-patch to all supported branches.
2012-06-30 22:43:50 +02:00
Node *pred_tree;
bool found_whole_row;
/* Convert text string to node tree */
pred_str = TextDatumGetCString(datum);
Prevent CREATE TABLE LIKE/INHERITS from (mis) copying whole-row Vars. If a CHECK constraint or index definition contained a whole-row Var (that is, "table.*"), an attempt to copy that definition via CREATE TABLE LIKE or table inheritance produced incorrect results: the copied Var still claimed to have the rowtype of the source table, rather than the created table. For the LIKE case, it seems reasonable to just throw error for this situation, since the point of LIKE is that the new table is not permanently coupled to the old, so there's no reason to assume its rowtype will stay compatible. In the inheritance case, we should ideally allow such constraints, but doing so will require nontrivial refactoring of CREATE TABLE processing (because we'd need to know the OID of the new table's rowtype before we adjust inherited CHECK constraints). In view of the lack of previous complaints, that doesn't seem worth the risk in a back-patched bug fix, so just make it throw error for the inheritance case as well. Along the way, replace change_varattnos_of_a_node() with a more robust function map_variable_attnos(), which is capable of being extended to handle insertion of ConvertRowtypeExpr whenever we get around to fixing the inheritance case nicely, and in the meantime it returns a failure indication to the caller so that a helpful message with some context can be thrown. Also, this code will do the right thing with subselects (if we ever allow them in CHECK or indexes), and it range-checks varattnos before using them to index into the map array. Per report from Sergey Konoplev. Back-patch to all supported branches.
2012-06-30 22:43:50 +02:00
pred_tree = (Node *) stringToNode(pred_str);
/* Adjust Vars to match new table's column numbering */
pred_tree = map_variable_attnos(pred_tree,
1, 0,
attmap,
InvalidOid, &found_whole_row);
Prevent CREATE TABLE LIKE/INHERITS from (mis) copying whole-row Vars. If a CHECK constraint or index definition contained a whole-row Var (that is, "table.*"), an attempt to copy that definition via CREATE TABLE LIKE or table inheritance produced incorrect results: the copied Var still claimed to have the rowtype of the source table, rather than the created table. For the LIKE case, it seems reasonable to just throw error for this situation, since the point of LIKE is that the new table is not permanently coupled to the old, so there's no reason to assume its rowtype will stay compatible. In the inheritance case, we should ideally allow such constraints, but doing so will require nontrivial refactoring of CREATE TABLE processing (because we'd need to know the OID of the new table's rowtype before we adjust inherited CHECK constraints). In view of the lack of previous complaints, that doesn't seem worth the risk in a back-patched bug fix, so just make it throw error for the inheritance case as well. Along the way, replace change_varattnos_of_a_node() with a more robust function map_variable_attnos(), which is capable of being extended to handle insertion of ConvertRowtypeExpr whenever we get around to fixing the inheritance case nicely, and in the meantime it returns a failure indication to the caller so that a helpful message with some context can be thrown. Also, this code will do the right thing with subselects (if we ever allow them in CHECK or indexes), and it range-checks varattnos before using them to index into the map array. Per report from Sergey Konoplev. Back-patch to all supported branches.
2012-06-30 22:43:50 +02:00
/* As in expandTableLikeClause, reject whole-row variables */
Prevent CREATE TABLE LIKE/INHERITS from (mis) copying whole-row Vars. If a CHECK constraint or index definition contained a whole-row Var (that is, "table.*"), an attempt to copy that definition via CREATE TABLE LIKE or table inheritance produced incorrect results: the copied Var still claimed to have the rowtype of the source table, rather than the created table. For the LIKE case, it seems reasonable to just throw error for this situation, since the point of LIKE is that the new table is not permanently coupled to the old, so there's no reason to assume its rowtype will stay compatible. In the inheritance case, we should ideally allow such constraints, but doing so will require nontrivial refactoring of CREATE TABLE processing (because we'd need to know the OID of the new table's rowtype before we adjust inherited CHECK constraints). In view of the lack of previous complaints, that doesn't seem worth the risk in a back-patched bug fix, so just make it throw error for the inheritance case as well. Along the way, replace change_varattnos_of_a_node() with a more robust function map_variable_attnos(), which is capable of being extended to handle insertion of ConvertRowtypeExpr whenever we get around to fixing the inheritance case nicely, and in the meantime it returns a failure indication to the caller so that a helpful message with some context can be thrown. Also, this code will do the right thing with subselects (if we ever allow them in CHECK or indexes), and it range-checks varattnos before using them to index into the map array. Per report from Sergey Konoplev. Back-patch to all supported branches.
2012-06-30 22:43:50 +02:00
if (found_whole_row)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot convert whole-row table reference"),
errdetail("Index \"%s\" contains a whole-row table reference.",
RelationGetRelationName(source_idx))));
index->whereClause = pred_tree;
}
/* Clean up */
ReleaseSysCache(ht_idxrel);
ReleaseSysCache(ht_am);
return index;
}
/*
* Generate a CreateStatsStmt node using information from an already existing
* extended statistic "source_statsid", for the rel identified by heapRel and
* heapRelid.
*/
static CreateStatsStmt *
generateClonedExtStatsStmt(RangeVar *heapRel, Oid heapRelid,
Oid source_statsid)
{
HeapTuple ht_stats;
Form_pg_statistic_ext statsrec;
CreateStatsStmt *stats;
List *stat_types = NIL;
List *def_names = NIL;
bool isnull;
Datum datum;
ArrayType *arr;
char *enabled;
int i;
Assert(OidIsValid(heapRelid));
Assert(heapRel != NULL);
/*
* Fetch pg_statistic_ext tuple of source statistics object.
*/
ht_stats = SearchSysCache1(STATEXTOID, ObjectIdGetDatum(source_statsid));
if (!HeapTupleIsValid(ht_stats))
elog(ERROR, "cache lookup failed for statistics object %u", source_statsid);
statsrec = (Form_pg_statistic_ext) GETSTRUCT(ht_stats);
/* Determine which statistics types exist */
datum = SysCacheGetAttrNotNull(STATEXTOID, ht_stats,
Anum_pg_statistic_ext_stxkind);
arr = DatumGetArrayTypeP(datum);
if (ARR_NDIM(arr) != 1 ||
ARR_HASNULL(arr) ||
ARR_ELEMTYPE(arr) != CHAROID)
elog(ERROR, "stxkind is not a 1-D char array");
enabled = (char *) ARR_DATA_PTR(arr);
for (i = 0; i < ARR_DIMS(arr)[0]; i++)
{
if (enabled[i] == STATS_EXT_NDISTINCT)
stat_types = lappend(stat_types, makeString("ndistinct"));
else if (enabled[i] == STATS_EXT_DEPENDENCIES)
stat_types = lappend(stat_types, makeString("dependencies"));
else if (enabled[i] == STATS_EXT_MCV)
stat_types = lappend(stat_types, makeString("mcv"));
Extended statistics on expressions Allow defining extended statistics on expressions, not just just on simple column references. With this commit, expressions are supported by all existing extended statistics kinds, improving the same types of estimates. A simple example may look like this: CREATE TABLE t (a int); CREATE STATISTICS s ON mod(a,10), mod(a,20) FROM t; ANALYZE t; The collected statistics are useful e.g. to estimate queries with those expressions in WHERE or GROUP BY clauses: SELECT * FROM t WHERE mod(a,10) = 0 AND mod(a,20) = 0; SELECT 1 FROM t GROUP BY mod(a,10), mod(a,20); This introduces new internal statistics kind 'e' (expressions) which is built automatically when the statistics object definition includes any expressions. This represents single-expression statistics, as if there was an expression index (but without the index maintenance overhead). The statistics is stored in pg_statistics_ext_data as an array of composite types, which is possible thanks to 79f6a942bd. CREATE STATISTICS allows building statistics on a single expression, in which case in which case it's not possible to specify statistics kinds. A new system view pg_stats_ext_exprs can be used to display expression statistics, similarly to pg_stats and pg_stats_ext views. ALTER TABLE ... ALTER COLUMN ... TYPE now treats indexes the same way it treats indexes, i.e. it drops and recreates the statistics. This means all statistics are reset, and we no longer try to preserve at least the functional dependencies. This should not be a major issue in practice, as the functional dependencies actually rely on per-column statistics, which were always reset anyway. Author: Tomas Vondra Reviewed-by: Justin Pryzby, Dean Rasheed, Zhihong Yu Discussion: https://postgr.es/m/ad7891d2-e90c-b446-9fe2-7419143847d7%40enterprisedb.com
2021-03-26 23:22:01 +01:00
else if (enabled[i] == STATS_EXT_EXPRESSIONS)
/* expression stats are not exposed to users */
continue;
else
elog(ERROR, "unrecognized statistics kind %c", enabled[i]);
}
/* Determine which columns the statistics are on */
for (i = 0; i < statsrec->stxkeys.dim1; i++)
{
Extended statistics on expressions Allow defining extended statistics on expressions, not just just on simple column references. With this commit, expressions are supported by all existing extended statistics kinds, improving the same types of estimates. A simple example may look like this: CREATE TABLE t (a int); CREATE STATISTICS s ON mod(a,10), mod(a,20) FROM t; ANALYZE t; The collected statistics are useful e.g. to estimate queries with those expressions in WHERE or GROUP BY clauses: SELECT * FROM t WHERE mod(a,10) = 0 AND mod(a,20) = 0; SELECT 1 FROM t GROUP BY mod(a,10), mod(a,20); This introduces new internal statistics kind 'e' (expressions) which is built automatically when the statistics object definition includes any expressions. This represents single-expression statistics, as if there was an expression index (but without the index maintenance overhead). The statistics is stored in pg_statistics_ext_data as an array of composite types, which is possible thanks to 79f6a942bd. CREATE STATISTICS allows building statistics on a single expression, in which case in which case it's not possible to specify statistics kinds. A new system view pg_stats_ext_exprs can be used to display expression statistics, similarly to pg_stats and pg_stats_ext views. ALTER TABLE ... ALTER COLUMN ... TYPE now treats indexes the same way it treats indexes, i.e. it drops and recreates the statistics. This means all statistics are reset, and we no longer try to preserve at least the functional dependencies. This should not be a major issue in practice, as the functional dependencies actually rely on per-column statistics, which were always reset anyway. Author: Tomas Vondra Reviewed-by: Justin Pryzby, Dean Rasheed, Zhihong Yu Discussion: https://postgr.es/m/ad7891d2-e90c-b446-9fe2-7419143847d7%40enterprisedb.com
2021-03-26 23:22:01 +01:00
StatsElem *selem = makeNode(StatsElem);
AttrNumber attnum = statsrec->stxkeys.values[i];
Extended statistics on expressions Allow defining extended statistics on expressions, not just just on simple column references. With this commit, expressions are supported by all existing extended statistics kinds, improving the same types of estimates. A simple example may look like this: CREATE TABLE t (a int); CREATE STATISTICS s ON mod(a,10), mod(a,20) FROM t; ANALYZE t; The collected statistics are useful e.g. to estimate queries with those expressions in WHERE or GROUP BY clauses: SELECT * FROM t WHERE mod(a,10) = 0 AND mod(a,20) = 0; SELECT 1 FROM t GROUP BY mod(a,10), mod(a,20); This introduces new internal statistics kind 'e' (expressions) which is built automatically when the statistics object definition includes any expressions. This represents single-expression statistics, as if there was an expression index (but without the index maintenance overhead). The statistics is stored in pg_statistics_ext_data as an array of composite types, which is possible thanks to 79f6a942bd. CREATE STATISTICS allows building statistics on a single expression, in which case in which case it's not possible to specify statistics kinds. A new system view pg_stats_ext_exprs can be used to display expression statistics, similarly to pg_stats and pg_stats_ext views. ALTER TABLE ... ALTER COLUMN ... TYPE now treats indexes the same way it treats indexes, i.e. it drops and recreates the statistics. This means all statistics are reset, and we no longer try to preserve at least the functional dependencies. This should not be a major issue in practice, as the functional dependencies actually rely on per-column statistics, which were always reset anyway. Author: Tomas Vondra Reviewed-by: Justin Pryzby, Dean Rasheed, Zhihong Yu Discussion: https://postgr.es/m/ad7891d2-e90c-b446-9fe2-7419143847d7%40enterprisedb.com
2021-03-26 23:22:01 +01:00
selem->name = get_attname(heapRelid, attnum, false);
selem->expr = NULL;
Extended statistics on expressions Allow defining extended statistics on expressions, not just just on simple column references. With this commit, expressions are supported by all existing extended statistics kinds, improving the same types of estimates. A simple example may look like this: CREATE TABLE t (a int); CREATE STATISTICS s ON mod(a,10), mod(a,20) FROM t; ANALYZE t; The collected statistics are useful e.g. to estimate queries with those expressions in WHERE or GROUP BY clauses: SELECT * FROM t WHERE mod(a,10) = 0 AND mod(a,20) = 0; SELECT 1 FROM t GROUP BY mod(a,10), mod(a,20); This introduces new internal statistics kind 'e' (expressions) which is built automatically when the statistics object definition includes any expressions. This represents single-expression statistics, as if there was an expression index (but without the index maintenance overhead). The statistics is stored in pg_statistics_ext_data as an array of composite types, which is possible thanks to 79f6a942bd. CREATE STATISTICS allows building statistics on a single expression, in which case in which case it's not possible to specify statistics kinds. A new system view pg_stats_ext_exprs can be used to display expression statistics, similarly to pg_stats and pg_stats_ext views. ALTER TABLE ... ALTER COLUMN ... TYPE now treats indexes the same way it treats indexes, i.e. it drops and recreates the statistics. This means all statistics are reset, and we no longer try to preserve at least the functional dependencies. This should not be a major issue in practice, as the functional dependencies actually rely on per-column statistics, which were always reset anyway. Author: Tomas Vondra Reviewed-by: Justin Pryzby, Dean Rasheed, Zhihong Yu Discussion: https://postgr.es/m/ad7891d2-e90c-b446-9fe2-7419143847d7%40enterprisedb.com
2021-03-26 23:22:01 +01:00
def_names = lappend(def_names, selem);
}
/*
* Now handle expressions, if there are any. The order (with respect to
* regular attributes) does not really matter for extended stats, so we
* simply append them after simple column references.
*
* XXX Some places during build/estimation treat expressions as if they
* are before attributes, but for the CREATE command that's entirely
Extended statistics on expressions Allow defining extended statistics on expressions, not just just on simple column references. With this commit, expressions are supported by all existing extended statistics kinds, improving the same types of estimates. A simple example may look like this: CREATE TABLE t (a int); CREATE STATISTICS s ON mod(a,10), mod(a,20) FROM t; ANALYZE t; The collected statistics are useful e.g. to estimate queries with those expressions in WHERE or GROUP BY clauses: SELECT * FROM t WHERE mod(a,10) = 0 AND mod(a,20) = 0; SELECT 1 FROM t GROUP BY mod(a,10), mod(a,20); This introduces new internal statistics kind 'e' (expressions) which is built automatically when the statistics object definition includes any expressions. This represents single-expression statistics, as if there was an expression index (but without the index maintenance overhead). The statistics is stored in pg_statistics_ext_data as an array of composite types, which is possible thanks to 79f6a942bd. CREATE STATISTICS allows building statistics on a single expression, in which case in which case it's not possible to specify statistics kinds. A new system view pg_stats_ext_exprs can be used to display expression statistics, similarly to pg_stats and pg_stats_ext views. ALTER TABLE ... ALTER COLUMN ... TYPE now treats indexes the same way it treats indexes, i.e. it drops and recreates the statistics. This means all statistics are reset, and we no longer try to preserve at least the functional dependencies. This should not be a major issue in practice, as the functional dependencies actually rely on per-column statistics, which were always reset anyway. Author: Tomas Vondra Reviewed-by: Justin Pryzby, Dean Rasheed, Zhihong Yu Discussion: https://postgr.es/m/ad7891d2-e90c-b446-9fe2-7419143847d7%40enterprisedb.com
2021-03-26 23:22:01 +01:00
* irrelevant.
*/
datum = SysCacheGetAttr(STATEXTOID, ht_stats,
Anum_pg_statistic_ext_stxexprs, &isnull);
if (!isnull)
{
ListCell *lc;
List *exprs = NIL;
char *exprsString;
exprsString = TextDatumGetCString(datum);
exprs = (List *) stringToNode(exprsString);
foreach(lc, exprs)
{
StatsElem *selem = makeNode(StatsElem);
selem->name = NULL;
selem->expr = (Node *) lfirst(lc);
def_names = lappend(def_names, selem);
}
pfree(exprsString);
}
/* finally, build the output node */
stats = makeNode(CreateStatsStmt);
stats->defnames = NULL;
stats->stat_types = stat_types;
stats->exprs = def_names;
stats->relations = list_make1(heapRel);
stats->stxcomment = NULL;
Extended statistics on expressions Allow defining extended statistics on expressions, not just just on simple column references. With this commit, expressions are supported by all existing extended statistics kinds, improving the same types of estimates. A simple example may look like this: CREATE TABLE t (a int); CREATE STATISTICS s ON mod(a,10), mod(a,20) FROM t; ANALYZE t; The collected statistics are useful e.g. to estimate queries with those expressions in WHERE or GROUP BY clauses: SELECT * FROM t WHERE mod(a,10) = 0 AND mod(a,20) = 0; SELECT 1 FROM t GROUP BY mod(a,10), mod(a,20); This introduces new internal statistics kind 'e' (expressions) which is built automatically when the statistics object definition includes any expressions. This represents single-expression statistics, as if there was an expression index (but without the index maintenance overhead). The statistics is stored in pg_statistics_ext_data as an array of composite types, which is possible thanks to 79f6a942bd. CREATE STATISTICS allows building statistics on a single expression, in which case in which case it's not possible to specify statistics kinds. A new system view pg_stats_ext_exprs can be used to display expression statistics, similarly to pg_stats and pg_stats_ext views. ALTER TABLE ... ALTER COLUMN ... TYPE now treats indexes the same way it treats indexes, i.e. it drops and recreates the statistics. This means all statistics are reset, and we no longer try to preserve at least the functional dependencies. This should not be a major issue in practice, as the functional dependencies actually rely on per-column statistics, which were always reset anyway. Author: Tomas Vondra Reviewed-by: Justin Pryzby, Dean Rasheed, Zhihong Yu Discussion: https://postgr.es/m/ad7891d2-e90c-b446-9fe2-7419143847d7%40enterprisedb.com
2021-03-26 23:22:01 +01:00
stats->transformed = true; /* don't need transformStatsStmt again */
stats->if_not_exists = false;
/* Clean up */
ReleaseSysCache(ht_stats);
return stats;
}
/*
* get_collation - fetch qualified name of a collation
*
* If collation is InvalidOid or is the default for the given actual_datatype,
* then the return value is NIL.
*/
static List *
get_collation(Oid collation, Oid actual_datatype)
{
List *result;
HeapTuple ht_coll;
Form_pg_collation coll_rec;
char *nsp_name;
char *coll_name;
if (!OidIsValid(collation))
return NIL; /* easy case */
if (collation == get_typcollation(actual_datatype))
return NIL; /* just let it default */
ht_coll = SearchSysCache1(COLLOID, ObjectIdGetDatum(collation));
if (!HeapTupleIsValid(ht_coll))
elog(ERROR, "cache lookup failed for collation %u", collation);
coll_rec = (Form_pg_collation) GETSTRUCT(ht_coll);
/* For simplicity, we always schema-qualify the name */
nsp_name = get_namespace_name(coll_rec->collnamespace);
coll_name = pstrdup(NameStr(coll_rec->collname));
result = list_make2(makeString(nsp_name), makeString(coll_name));
ReleaseSysCache(ht_coll);
return result;
}
/*
* get_opclass - fetch qualified name of an index operator class
*
* If the opclass is the default for the given actual_datatype, then
* the return value is NIL.
*/
static List *
get_opclass(Oid opclass, Oid actual_datatype)
{
List *result = NIL;
HeapTuple ht_opc;
Form_pg_opclass opc_rec;
ht_opc = SearchSysCache1(CLAOID, ObjectIdGetDatum(opclass));
if (!HeapTupleIsValid(ht_opc))
elog(ERROR, "cache lookup failed for opclass %u", opclass);
opc_rec = (Form_pg_opclass) GETSTRUCT(ht_opc);
if (GetDefaultOpClass(actual_datatype, opc_rec->opcmethod) != opclass)
{
/* For simplicity, we always schema-qualify the name */
char *nsp_name = get_namespace_name(opc_rec->opcnamespace);
char *opc_name = pstrdup(NameStr(opc_rec->opcname));
result = list_make2(makeString(nsp_name), makeString(opc_name));
}
ReleaseSysCache(ht_opc);
return result;
}
/*
* transformIndexConstraints
* Handle UNIQUE, PRIMARY KEY, EXCLUDE constraints, which create indexes.
* We also merge in any index definitions arising from
* LIKE ... INCLUDING INDEXES.
*/
static void
transformIndexConstraints(CreateStmtContext *cxt)
{
IndexStmt *index;
List *indexlist = NIL;
Avoid order-of-execution problems with ALTER TABLE ADD PRIMARY KEY. Up to now, DefineIndex() was responsible for adding attnotnull constraints to the columns of a primary key, in any case where it hadn't been convenient for transformIndexConstraint() to mark those columns as is_not_null. It (or rather its minion index_check_primary_key) did this by executing an ALTER TABLE SET NOT NULL command for the target table. The trouble with this solution is that if we're creating the index due to ALTER TABLE ADD PRIMARY KEY, and the outer ALTER TABLE has additional sub-commands, the inner ALTER TABLE's operations executed at the wrong time with respect to the outer ALTER TABLE's operations. In particular, the inner ALTER would perform a validation scan at a point where the table's storage might be inconsistent with its catalog entries. (This is on the hairy edge of being a security problem, but AFAICS it isn't one because the inner scan would only be interested in the tuples' null bitmaps.) This can result in unexpected failures, such as the one seen in bug #15580 from Allison Kaptur. To fix, let's remove the attempt to do SET NOT NULL from DefineIndex(), reducing index_check_primary_key's role to verifying that the columns are already not null. (It shouldn't ever see such a case, but it seems wise to keep the check for safety.) Instead, make transformIndexConstraint() generate ALTER TABLE SET NOT NULL subcommands to be executed ahead of the ADD PRIMARY KEY operation in every case where it can't force the column to be created already-not-null. This requires only minor surgery in parse_utilcmd.c, and it makes for a much more satisfying spec for transformIndexConstraint(): it's no longer having to take it on faith that someone else will handle addition of NOT NULL constraints. To make that work, we have to move the execution of AT_SetNotNull into an ALTER pass that executes ahead of AT_PASS_ADD_INDEX. I moved it to AT_PASS_COL_ATTRS, and put that after AT_PASS_ADD_COL to avoid failure when the column is being added in the same command. This incidentally fixes a bug in the only previous usage of AT_PASS_COL_ATTRS, for AT_SetIdentity: it didn't work either for a newly-added column. Playing around with this exposed a separate bug in ALTER TABLE ONLY ... ADD PRIMARY KEY for partitioned tables. The intent of the ONLY modifier in that context is to prevent doing anything that would require holding lock for a long time --- but the implied SET NOT NULL would recurse to the child partitions, and do an expensive validation scan for any child where the column(s) were not already NOT NULL. To fix that, invent a new ALTER subcommand AT_CheckNotNull that just insists that a child column be already NOT NULL, and apply that, not AT_SetNotNull, when recursing to children in this scenario. This results in a slightly laxer definition of ALTER TABLE ONLY ... SET NOT NULL for partitioned tables, too: that command will now work as long as all children are already NOT NULL, whereas before it just threw up its hands if there were any partitions. In passing, clean up the API of generateClonedIndexStmt(): remove a useless argument, ensure that the output argument is not left undefined, update the header comment. A small side effect of this change is that no-such-column errors in ALTER TABLE ADD PRIMARY KEY now produce a different message that includes the table name, because they are now detected by the SET NOT NULL step which has historically worded its error that way. That seems fine to me, so I didn't make any effort to avoid the wording change. The basic bug #15580 is of very long standing, and these other bugs aren't new in v12 either. However, this is a pretty significant change in the way ALTER TABLE ADD PRIMARY KEY works. On balance it seems best not to back-patch, at least not till we get some more confidence that this patch has no new bugs. Patch by me, but thanks to Jie Zhang for a preliminary version. Discussion: https://postgr.es/m/15580-d1a6de5a3d65da51@postgresql.org Discussion: https://postgr.es/m/1396E95157071C4EBBA51892C5368521017F2E6E63@G08CNEXMBPEKD02.g08.fujitsu.local
2019-04-23 18:25:27 +02:00
List *finalindexlist = NIL;
ListCell *lc;
/*
* Run through the constraints that need to generate an index. For PRIMARY
* KEY, mark each column as NOT NULL and create an index. For UNIQUE or
* EXCLUDE, create an index as for PRIMARY KEY, but do not insist on NOT
* NULL.
*/
foreach(lc, cxt->ixconstraints)
{
Constraint *constraint = lfirst_node(Constraint, lc);
Assert(constraint->contype == CONSTR_PRIMARY ||
constraint->contype == CONSTR_UNIQUE ||
constraint->contype == CONSTR_EXCLUSION);
index = transformIndexConstraint(constraint, cxt);
indexlist = lappend(indexlist, index);
}
/*
* Scan the index list and remove any redundant index specifications. This
* can happen if, for instance, the user writes UNIQUE PRIMARY KEY. A
* strict reading of SQL would suggest raising an error instead, but that
* strikes me as too anal-retentive. - tgl 2001-02-14
*
* XXX in ALTER TABLE case, it'd be nice to look for duplicate
* pre-existing indexes, too.
*/
if (cxt->pkey != NULL)
{
/* Make sure we keep the PKEY index in preference to others... */
Avoid order-of-execution problems with ALTER TABLE ADD PRIMARY KEY. Up to now, DefineIndex() was responsible for adding attnotnull constraints to the columns of a primary key, in any case where it hadn't been convenient for transformIndexConstraint() to mark those columns as is_not_null. It (or rather its minion index_check_primary_key) did this by executing an ALTER TABLE SET NOT NULL command for the target table. The trouble with this solution is that if we're creating the index due to ALTER TABLE ADD PRIMARY KEY, and the outer ALTER TABLE has additional sub-commands, the inner ALTER TABLE's operations executed at the wrong time with respect to the outer ALTER TABLE's operations. In particular, the inner ALTER would perform a validation scan at a point where the table's storage might be inconsistent with its catalog entries. (This is on the hairy edge of being a security problem, but AFAICS it isn't one because the inner scan would only be interested in the tuples' null bitmaps.) This can result in unexpected failures, such as the one seen in bug #15580 from Allison Kaptur. To fix, let's remove the attempt to do SET NOT NULL from DefineIndex(), reducing index_check_primary_key's role to verifying that the columns are already not null. (It shouldn't ever see such a case, but it seems wise to keep the check for safety.) Instead, make transformIndexConstraint() generate ALTER TABLE SET NOT NULL subcommands to be executed ahead of the ADD PRIMARY KEY operation in every case where it can't force the column to be created already-not-null. This requires only minor surgery in parse_utilcmd.c, and it makes for a much more satisfying spec for transformIndexConstraint(): it's no longer having to take it on faith that someone else will handle addition of NOT NULL constraints. To make that work, we have to move the execution of AT_SetNotNull into an ALTER pass that executes ahead of AT_PASS_ADD_INDEX. I moved it to AT_PASS_COL_ATTRS, and put that after AT_PASS_ADD_COL to avoid failure when the column is being added in the same command. This incidentally fixes a bug in the only previous usage of AT_PASS_COL_ATTRS, for AT_SetIdentity: it didn't work either for a newly-added column. Playing around with this exposed a separate bug in ALTER TABLE ONLY ... ADD PRIMARY KEY for partitioned tables. The intent of the ONLY modifier in that context is to prevent doing anything that would require holding lock for a long time --- but the implied SET NOT NULL would recurse to the child partitions, and do an expensive validation scan for any child where the column(s) were not already NOT NULL. To fix that, invent a new ALTER subcommand AT_CheckNotNull that just insists that a child column be already NOT NULL, and apply that, not AT_SetNotNull, when recursing to children in this scenario. This results in a slightly laxer definition of ALTER TABLE ONLY ... SET NOT NULL for partitioned tables, too: that command will now work as long as all children are already NOT NULL, whereas before it just threw up its hands if there were any partitions. In passing, clean up the API of generateClonedIndexStmt(): remove a useless argument, ensure that the output argument is not left undefined, update the header comment. A small side effect of this change is that no-such-column errors in ALTER TABLE ADD PRIMARY KEY now produce a different message that includes the table name, because they are now detected by the SET NOT NULL step which has historically worded its error that way. That seems fine to me, so I didn't make any effort to avoid the wording change. The basic bug #15580 is of very long standing, and these other bugs aren't new in v12 either. However, this is a pretty significant change in the way ALTER TABLE ADD PRIMARY KEY works. On balance it seems best not to back-patch, at least not till we get some more confidence that this patch has no new bugs. Patch by me, but thanks to Jie Zhang for a preliminary version. Discussion: https://postgr.es/m/15580-d1a6de5a3d65da51@postgresql.org Discussion: https://postgr.es/m/1396E95157071C4EBBA51892C5368521017F2E6E63@G08CNEXMBPEKD02.g08.fujitsu.local
2019-04-23 18:25:27 +02:00
finalindexlist = list_make1(cxt->pkey);
}
foreach(lc, indexlist)
{
bool keep = true;
ListCell *k;
index = lfirst(lc);
Avoid order-of-execution problems with ALTER TABLE ADD PRIMARY KEY. Up to now, DefineIndex() was responsible for adding attnotnull constraints to the columns of a primary key, in any case where it hadn't been convenient for transformIndexConstraint() to mark those columns as is_not_null. It (or rather its minion index_check_primary_key) did this by executing an ALTER TABLE SET NOT NULL command for the target table. The trouble with this solution is that if we're creating the index due to ALTER TABLE ADD PRIMARY KEY, and the outer ALTER TABLE has additional sub-commands, the inner ALTER TABLE's operations executed at the wrong time with respect to the outer ALTER TABLE's operations. In particular, the inner ALTER would perform a validation scan at a point where the table's storage might be inconsistent with its catalog entries. (This is on the hairy edge of being a security problem, but AFAICS it isn't one because the inner scan would only be interested in the tuples' null bitmaps.) This can result in unexpected failures, such as the one seen in bug #15580 from Allison Kaptur. To fix, let's remove the attempt to do SET NOT NULL from DefineIndex(), reducing index_check_primary_key's role to verifying that the columns are already not null. (It shouldn't ever see such a case, but it seems wise to keep the check for safety.) Instead, make transformIndexConstraint() generate ALTER TABLE SET NOT NULL subcommands to be executed ahead of the ADD PRIMARY KEY operation in every case where it can't force the column to be created already-not-null. This requires only minor surgery in parse_utilcmd.c, and it makes for a much more satisfying spec for transformIndexConstraint(): it's no longer having to take it on faith that someone else will handle addition of NOT NULL constraints. To make that work, we have to move the execution of AT_SetNotNull into an ALTER pass that executes ahead of AT_PASS_ADD_INDEX. I moved it to AT_PASS_COL_ATTRS, and put that after AT_PASS_ADD_COL to avoid failure when the column is being added in the same command. This incidentally fixes a bug in the only previous usage of AT_PASS_COL_ATTRS, for AT_SetIdentity: it didn't work either for a newly-added column. Playing around with this exposed a separate bug in ALTER TABLE ONLY ... ADD PRIMARY KEY for partitioned tables. The intent of the ONLY modifier in that context is to prevent doing anything that would require holding lock for a long time --- but the implied SET NOT NULL would recurse to the child partitions, and do an expensive validation scan for any child where the column(s) were not already NOT NULL. To fix that, invent a new ALTER subcommand AT_CheckNotNull that just insists that a child column be already NOT NULL, and apply that, not AT_SetNotNull, when recursing to children in this scenario. This results in a slightly laxer definition of ALTER TABLE ONLY ... SET NOT NULL for partitioned tables, too: that command will now work as long as all children are already NOT NULL, whereas before it just threw up its hands if there were any partitions. In passing, clean up the API of generateClonedIndexStmt(): remove a useless argument, ensure that the output argument is not left undefined, update the header comment. A small side effect of this change is that no-such-column errors in ALTER TABLE ADD PRIMARY KEY now produce a different message that includes the table name, because they are now detected by the SET NOT NULL step which has historically worded its error that way. That seems fine to me, so I didn't make any effort to avoid the wording change. The basic bug #15580 is of very long standing, and these other bugs aren't new in v12 either. However, this is a pretty significant change in the way ALTER TABLE ADD PRIMARY KEY works. On balance it seems best not to back-patch, at least not till we get some more confidence that this patch has no new bugs. Patch by me, but thanks to Jie Zhang for a preliminary version. Discussion: https://postgr.es/m/15580-d1a6de5a3d65da51@postgresql.org Discussion: https://postgr.es/m/1396E95157071C4EBBA51892C5368521017F2E6E63@G08CNEXMBPEKD02.g08.fujitsu.local
2019-04-23 18:25:27 +02:00
/* if it's pkey, it's already in finalindexlist */
if (index == cxt->pkey)
continue;
Avoid order-of-execution problems with ALTER TABLE ADD PRIMARY KEY. Up to now, DefineIndex() was responsible for adding attnotnull constraints to the columns of a primary key, in any case where it hadn't been convenient for transformIndexConstraint() to mark those columns as is_not_null. It (or rather its minion index_check_primary_key) did this by executing an ALTER TABLE SET NOT NULL command for the target table. The trouble with this solution is that if we're creating the index due to ALTER TABLE ADD PRIMARY KEY, and the outer ALTER TABLE has additional sub-commands, the inner ALTER TABLE's operations executed at the wrong time with respect to the outer ALTER TABLE's operations. In particular, the inner ALTER would perform a validation scan at a point where the table's storage might be inconsistent with its catalog entries. (This is on the hairy edge of being a security problem, but AFAICS it isn't one because the inner scan would only be interested in the tuples' null bitmaps.) This can result in unexpected failures, such as the one seen in bug #15580 from Allison Kaptur. To fix, let's remove the attempt to do SET NOT NULL from DefineIndex(), reducing index_check_primary_key's role to verifying that the columns are already not null. (It shouldn't ever see such a case, but it seems wise to keep the check for safety.) Instead, make transformIndexConstraint() generate ALTER TABLE SET NOT NULL subcommands to be executed ahead of the ADD PRIMARY KEY operation in every case where it can't force the column to be created already-not-null. This requires only minor surgery in parse_utilcmd.c, and it makes for a much more satisfying spec for transformIndexConstraint(): it's no longer having to take it on faith that someone else will handle addition of NOT NULL constraints. To make that work, we have to move the execution of AT_SetNotNull into an ALTER pass that executes ahead of AT_PASS_ADD_INDEX. I moved it to AT_PASS_COL_ATTRS, and put that after AT_PASS_ADD_COL to avoid failure when the column is being added in the same command. This incidentally fixes a bug in the only previous usage of AT_PASS_COL_ATTRS, for AT_SetIdentity: it didn't work either for a newly-added column. Playing around with this exposed a separate bug in ALTER TABLE ONLY ... ADD PRIMARY KEY for partitioned tables. The intent of the ONLY modifier in that context is to prevent doing anything that would require holding lock for a long time --- but the implied SET NOT NULL would recurse to the child partitions, and do an expensive validation scan for any child where the column(s) were not already NOT NULL. To fix that, invent a new ALTER subcommand AT_CheckNotNull that just insists that a child column be already NOT NULL, and apply that, not AT_SetNotNull, when recursing to children in this scenario. This results in a slightly laxer definition of ALTER TABLE ONLY ... SET NOT NULL for partitioned tables, too: that command will now work as long as all children are already NOT NULL, whereas before it just threw up its hands if there were any partitions. In passing, clean up the API of generateClonedIndexStmt(): remove a useless argument, ensure that the output argument is not left undefined, update the header comment. A small side effect of this change is that no-such-column errors in ALTER TABLE ADD PRIMARY KEY now produce a different message that includes the table name, because they are now detected by the SET NOT NULL step which has historically worded its error that way. That seems fine to me, so I didn't make any effort to avoid the wording change. The basic bug #15580 is of very long standing, and these other bugs aren't new in v12 either. However, this is a pretty significant change in the way ALTER TABLE ADD PRIMARY KEY works. On balance it seems best not to back-patch, at least not till we get some more confidence that this patch has no new bugs. Patch by me, but thanks to Jie Zhang for a preliminary version. Discussion: https://postgr.es/m/15580-d1a6de5a3d65da51@postgresql.org Discussion: https://postgr.es/m/1396E95157071C4EBBA51892C5368521017F2E6E63@G08CNEXMBPEKD02.g08.fujitsu.local
2019-04-23 18:25:27 +02:00
foreach(k, finalindexlist)
{
IndexStmt *priorindex = lfirst(k);
if (equal(index->indexParams, priorindex->indexParams) &&
equal(index->indexIncludingParams, priorindex->indexIncludingParams) &&
equal(index->whereClause, priorindex->whereClause) &&
equal(index->excludeOpNames, priorindex->excludeOpNames) &&
strcmp(index->accessMethod, priorindex->accessMethod) == 0 &&
index->nulls_not_distinct == priorindex->nulls_not_distinct &&
index->deferrable == priorindex->deferrable &&
index->initdeferred == priorindex->initdeferred)
{
priorindex->unique |= index->unique;
/*
* If the prior index is as yet unnamed, and this one is
* named, then transfer the name to the prior index. This
* ensures that if we have named and unnamed constraints,
* we'll use (at least one of) the names for the index.
*/
if (priorindex->idxname == NULL)
priorindex->idxname = index->idxname;
keep = false;
break;
}
}
if (keep)
Avoid order-of-execution problems with ALTER TABLE ADD PRIMARY KEY. Up to now, DefineIndex() was responsible for adding attnotnull constraints to the columns of a primary key, in any case where it hadn't been convenient for transformIndexConstraint() to mark those columns as is_not_null. It (or rather its minion index_check_primary_key) did this by executing an ALTER TABLE SET NOT NULL command for the target table. The trouble with this solution is that if we're creating the index due to ALTER TABLE ADD PRIMARY KEY, and the outer ALTER TABLE has additional sub-commands, the inner ALTER TABLE's operations executed at the wrong time with respect to the outer ALTER TABLE's operations. In particular, the inner ALTER would perform a validation scan at a point where the table's storage might be inconsistent with its catalog entries. (This is on the hairy edge of being a security problem, but AFAICS it isn't one because the inner scan would only be interested in the tuples' null bitmaps.) This can result in unexpected failures, such as the one seen in bug #15580 from Allison Kaptur. To fix, let's remove the attempt to do SET NOT NULL from DefineIndex(), reducing index_check_primary_key's role to verifying that the columns are already not null. (It shouldn't ever see such a case, but it seems wise to keep the check for safety.) Instead, make transformIndexConstraint() generate ALTER TABLE SET NOT NULL subcommands to be executed ahead of the ADD PRIMARY KEY operation in every case where it can't force the column to be created already-not-null. This requires only minor surgery in parse_utilcmd.c, and it makes for a much more satisfying spec for transformIndexConstraint(): it's no longer having to take it on faith that someone else will handle addition of NOT NULL constraints. To make that work, we have to move the execution of AT_SetNotNull into an ALTER pass that executes ahead of AT_PASS_ADD_INDEX. I moved it to AT_PASS_COL_ATTRS, and put that after AT_PASS_ADD_COL to avoid failure when the column is being added in the same command. This incidentally fixes a bug in the only previous usage of AT_PASS_COL_ATTRS, for AT_SetIdentity: it didn't work either for a newly-added column. Playing around with this exposed a separate bug in ALTER TABLE ONLY ... ADD PRIMARY KEY for partitioned tables. The intent of the ONLY modifier in that context is to prevent doing anything that would require holding lock for a long time --- but the implied SET NOT NULL would recurse to the child partitions, and do an expensive validation scan for any child where the column(s) were not already NOT NULL. To fix that, invent a new ALTER subcommand AT_CheckNotNull that just insists that a child column be already NOT NULL, and apply that, not AT_SetNotNull, when recursing to children in this scenario. This results in a slightly laxer definition of ALTER TABLE ONLY ... SET NOT NULL for partitioned tables, too: that command will now work as long as all children are already NOT NULL, whereas before it just threw up its hands if there were any partitions. In passing, clean up the API of generateClonedIndexStmt(): remove a useless argument, ensure that the output argument is not left undefined, update the header comment. A small side effect of this change is that no-such-column errors in ALTER TABLE ADD PRIMARY KEY now produce a different message that includes the table name, because they are now detected by the SET NOT NULL step which has historically worded its error that way. That seems fine to me, so I didn't make any effort to avoid the wording change. The basic bug #15580 is of very long standing, and these other bugs aren't new in v12 either. However, this is a pretty significant change in the way ALTER TABLE ADD PRIMARY KEY works. On balance it seems best not to back-patch, at least not till we get some more confidence that this patch has no new bugs. Patch by me, but thanks to Jie Zhang for a preliminary version. Discussion: https://postgr.es/m/15580-d1a6de5a3d65da51@postgresql.org Discussion: https://postgr.es/m/1396E95157071C4EBBA51892C5368521017F2E6E63@G08CNEXMBPEKD02.g08.fujitsu.local
2019-04-23 18:25:27 +02:00
finalindexlist = lappend(finalindexlist, index);
}
Avoid order-of-execution problems with ALTER TABLE ADD PRIMARY KEY. Up to now, DefineIndex() was responsible for adding attnotnull constraints to the columns of a primary key, in any case where it hadn't been convenient for transformIndexConstraint() to mark those columns as is_not_null. It (or rather its minion index_check_primary_key) did this by executing an ALTER TABLE SET NOT NULL command for the target table. The trouble with this solution is that if we're creating the index due to ALTER TABLE ADD PRIMARY KEY, and the outer ALTER TABLE has additional sub-commands, the inner ALTER TABLE's operations executed at the wrong time with respect to the outer ALTER TABLE's operations. In particular, the inner ALTER would perform a validation scan at a point where the table's storage might be inconsistent with its catalog entries. (This is on the hairy edge of being a security problem, but AFAICS it isn't one because the inner scan would only be interested in the tuples' null bitmaps.) This can result in unexpected failures, such as the one seen in bug #15580 from Allison Kaptur. To fix, let's remove the attempt to do SET NOT NULL from DefineIndex(), reducing index_check_primary_key's role to verifying that the columns are already not null. (It shouldn't ever see such a case, but it seems wise to keep the check for safety.) Instead, make transformIndexConstraint() generate ALTER TABLE SET NOT NULL subcommands to be executed ahead of the ADD PRIMARY KEY operation in every case where it can't force the column to be created already-not-null. This requires only minor surgery in parse_utilcmd.c, and it makes for a much more satisfying spec for transformIndexConstraint(): it's no longer having to take it on faith that someone else will handle addition of NOT NULL constraints. To make that work, we have to move the execution of AT_SetNotNull into an ALTER pass that executes ahead of AT_PASS_ADD_INDEX. I moved it to AT_PASS_COL_ATTRS, and put that after AT_PASS_ADD_COL to avoid failure when the column is being added in the same command. This incidentally fixes a bug in the only previous usage of AT_PASS_COL_ATTRS, for AT_SetIdentity: it didn't work either for a newly-added column. Playing around with this exposed a separate bug in ALTER TABLE ONLY ... ADD PRIMARY KEY for partitioned tables. The intent of the ONLY modifier in that context is to prevent doing anything that would require holding lock for a long time --- but the implied SET NOT NULL would recurse to the child partitions, and do an expensive validation scan for any child where the column(s) were not already NOT NULL. To fix that, invent a new ALTER subcommand AT_CheckNotNull that just insists that a child column be already NOT NULL, and apply that, not AT_SetNotNull, when recursing to children in this scenario. This results in a slightly laxer definition of ALTER TABLE ONLY ... SET NOT NULL for partitioned tables, too: that command will now work as long as all children are already NOT NULL, whereas before it just threw up its hands if there were any partitions. In passing, clean up the API of generateClonedIndexStmt(): remove a useless argument, ensure that the output argument is not left undefined, update the header comment. A small side effect of this change is that no-such-column errors in ALTER TABLE ADD PRIMARY KEY now produce a different message that includes the table name, because they are now detected by the SET NOT NULL step which has historically worded its error that way. That seems fine to me, so I didn't make any effort to avoid the wording change. The basic bug #15580 is of very long standing, and these other bugs aren't new in v12 either. However, this is a pretty significant change in the way ALTER TABLE ADD PRIMARY KEY works. On balance it seems best not to back-patch, at least not till we get some more confidence that this patch has no new bugs. Patch by me, but thanks to Jie Zhang for a preliminary version. Discussion: https://postgr.es/m/15580-d1a6de5a3d65da51@postgresql.org Discussion: https://postgr.es/m/1396E95157071C4EBBA51892C5368521017F2E6E63@G08CNEXMBPEKD02.g08.fujitsu.local
2019-04-23 18:25:27 +02:00
/*
* Now append all the IndexStmts to cxt->alist. If we generated an ALTER
* TABLE SET NOT NULL statement to support a primary key, it's already in
* cxt->alist.
Avoid order-of-execution problems with ALTER TABLE ADD PRIMARY KEY. Up to now, DefineIndex() was responsible for adding attnotnull constraints to the columns of a primary key, in any case where it hadn't been convenient for transformIndexConstraint() to mark those columns as is_not_null. It (or rather its minion index_check_primary_key) did this by executing an ALTER TABLE SET NOT NULL command for the target table. The trouble with this solution is that if we're creating the index due to ALTER TABLE ADD PRIMARY KEY, and the outer ALTER TABLE has additional sub-commands, the inner ALTER TABLE's operations executed at the wrong time with respect to the outer ALTER TABLE's operations. In particular, the inner ALTER would perform a validation scan at a point where the table's storage might be inconsistent with its catalog entries. (This is on the hairy edge of being a security problem, but AFAICS it isn't one because the inner scan would only be interested in the tuples' null bitmaps.) This can result in unexpected failures, such as the one seen in bug #15580 from Allison Kaptur. To fix, let's remove the attempt to do SET NOT NULL from DefineIndex(), reducing index_check_primary_key's role to verifying that the columns are already not null. (It shouldn't ever see such a case, but it seems wise to keep the check for safety.) Instead, make transformIndexConstraint() generate ALTER TABLE SET NOT NULL subcommands to be executed ahead of the ADD PRIMARY KEY operation in every case where it can't force the column to be created already-not-null. This requires only minor surgery in parse_utilcmd.c, and it makes for a much more satisfying spec for transformIndexConstraint(): it's no longer having to take it on faith that someone else will handle addition of NOT NULL constraints. To make that work, we have to move the execution of AT_SetNotNull into an ALTER pass that executes ahead of AT_PASS_ADD_INDEX. I moved it to AT_PASS_COL_ATTRS, and put that after AT_PASS_ADD_COL to avoid failure when the column is being added in the same command. This incidentally fixes a bug in the only previous usage of AT_PASS_COL_ATTRS, for AT_SetIdentity: it didn't work either for a newly-added column. Playing around with this exposed a separate bug in ALTER TABLE ONLY ... ADD PRIMARY KEY for partitioned tables. The intent of the ONLY modifier in that context is to prevent doing anything that would require holding lock for a long time --- but the implied SET NOT NULL would recurse to the child partitions, and do an expensive validation scan for any child where the column(s) were not already NOT NULL. To fix that, invent a new ALTER subcommand AT_CheckNotNull that just insists that a child column be already NOT NULL, and apply that, not AT_SetNotNull, when recursing to children in this scenario. This results in a slightly laxer definition of ALTER TABLE ONLY ... SET NOT NULL for partitioned tables, too: that command will now work as long as all children are already NOT NULL, whereas before it just threw up its hands if there were any partitions. In passing, clean up the API of generateClonedIndexStmt(): remove a useless argument, ensure that the output argument is not left undefined, update the header comment. A small side effect of this change is that no-such-column errors in ALTER TABLE ADD PRIMARY KEY now produce a different message that includes the table name, because they are now detected by the SET NOT NULL step which has historically worded its error that way. That seems fine to me, so I didn't make any effort to avoid the wording change. The basic bug #15580 is of very long standing, and these other bugs aren't new in v12 either. However, this is a pretty significant change in the way ALTER TABLE ADD PRIMARY KEY works. On balance it seems best not to back-patch, at least not till we get some more confidence that this patch has no new bugs. Patch by me, but thanks to Jie Zhang for a preliminary version. Discussion: https://postgr.es/m/15580-d1a6de5a3d65da51@postgresql.org Discussion: https://postgr.es/m/1396E95157071C4EBBA51892C5368521017F2E6E63@G08CNEXMBPEKD02.g08.fujitsu.local
2019-04-23 18:25:27 +02:00
*/
cxt->alist = list_concat(cxt->alist, finalindexlist);
}
/*
* transformIndexConstraint
* Transform one UNIQUE, PRIMARY KEY, or EXCLUDE constraint for
* transformIndexConstraints.
Avoid order-of-execution problems with ALTER TABLE ADD PRIMARY KEY. Up to now, DefineIndex() was responsible for adding attnotnull constraints to the columns of a primary key, in any case where it hadn't been convenient for transformIndexConstraint() to mark those columns as is_not_null. It (or rather its minion index_check_primary_key) did this by executing an ALTER TABLE SET NOT NULL command for the target table. The trouble with this solution is that if we're creating the index due to ALTER TABLE ADD PRIMARY KEY, and the outer ALTER TABLE has additional sub-commands, the inner ALTER TABLE's operations executed at the wrong time with respect to the outer ALTER TABLE's operations. In particular, the inner ALTER would perform a validation scan at a point where the table's storage might be inconsistent with its catalog entries. (This is on the hairy edge of being a security problem, but AFAICS it isn't one because the inner scan would only be interested in the tuples' null bitmaps.) This can result in unexpected failures, such as the one seen in bug #15580 from Allison Kaptur. To fix, let's remove the attempt to do SET NOT NULL from DefineIndex(), reducing index_check_primary_key's role to verifying that the columns are already not null. (It shouldn't ever see such a case, but it seems wise to keep the check for safety.) Instead, make transformIndexConstraint() generate ALTER TABLE SET NOT NULL subcommands to be executed ahead of the ADD PRIMARY KEY operation in every case where it can't force the column to be created already-not-null. This requires only minor surgery in parse_utilcmd.c, and it makes for a much more satisfying spec for transformIndexConstraint(): it's no longer having to take it on faith that someone else will handle addition of NOT NULL constraints. To make that work, we have to move the execution of AT_SetNotNull into an ALTER pass that executes ahead of AT_PASS_ADD_INDEX. I moved it to AT_PASS_COL_ATTRS, and put that after AT_PASS_ADD_COL to avoid failure when the column is being added in the same command. This incidentally fixes a bug in the only previous usage of AT_PASS_COL_ATTRS, for AT_SetIdentity: it didn't work either for a newly-added column. Playing around with this exposed a separate bug in ALTER TABLE ONLY ... ADD PRIMARY KEY for partitioned tables. The intent of the ONLY modifier in that context is to prevent doing anything that would require holding lock for a long time --- but the implied SET NOT NULL would recurse to the child partitions, and do an expensive validation scan for any child where the column(s) were not already NOT NULL. To fix that, invent a new ALTER subcommand AT_CheckNotNull that just insists that a child column be already NOT NULL, and apply that, not AT_SetNotNull, when recursing to children in this scenario. This results in a slightly laxer definition of ALTER TABLE ONLY ... SET NOT NULL for partitioned tables, too: that command will now work as long as all children are already NOT NULL, whereas before it just threw up its hands if there were any partitions. In passing, clean up the API of generateClonedIndexStmt(): remove a useless argument, ensure that the output argument is not left undefined, update the header comment. A small side effect of this change is that no-such-column errors in ALTER TABLE ADD PRIMARY KEY now produce a different message that includes the table name, because they are now detected by the SET NOT NULL step which has historically worded its error that way. That seems fine to me, so I didn't make any effort to avoid the wording change. The basic bug #15580 is of very long standing, and these other bugs aren't new in v12 either. However, this is a pretty significant change in the way ALTER TABLE ADD PRIMARY KEY works. On balance it seems best not to back-patch, at least not till we get some more confidence that this patch has no new bugs. Patch by me, but thanks to Jie Zhang for a preliminary version. Discussion: https://postgr.es/m/15580-d1a6de5a3d65da51@postgresql.org Discussion: https://postgr.es/m/1396E95157071C4EBBA51892C5368521017F2E6E63@G08CNEXMBPEKD02.g08.fujitsu.local
2019-04-23 18:25:27 +02:00
*
* We return an IndexStmt. For a PRIMARY KEY constraint, we additionally
* produce NOT NULL constraints, either by marking ColumnDefs in cxt->columns
* as is_not_null or by adding an ALTER TABLE SET NOT NULL command to
* cxt->alist.
*/
static IndexStmt *
transformIndexConstraint(Constraint *constraint, CreateStmtContext *cxt)
{
IndexStmt *index;
Avoid order-of-execution problems with ALTER TABLE ADD PRIMARY KEY. Up to now, DefineIndex() was responsible for adding attnotnull constraints to the columns of a primary key, in any case where it hadn't been convenient for transformIndexConstraint() to mark those columns as is_not_null. It (or rather its minion index_check_primary_key) did this by executing an ALTER TABLE SET NOT NULL command for the target table. The trouble with this solution is that if we're creating the index due to ALTER TABLE ADD PRIMARY KEY, and the outer ALTER TABLE has additional sub-commands, the inner ALTER TABLE's operations executed at the wrong time with respect to the outer ALTER TABLE's operations. In particular, the inner ALTER would perform a validation scan at a point where the table's storage might be inconsistent with its catalog entries. (This is on the hairy edge of being a security problem, but AFAICS it isn't one because the inner scan would only be interested in the tuples' null bitmaps.) This can result in unexpected failures, such as the one seen in bug #15580 from Allison Kaptur. To fix, let's remove the attempt to do SET NOT NULL from DefineIndex(), reducing index_check_primary_key's role to verifying that the columns are already not null. (It shouldn't ever see such a case, but it seems wise to keep the check for safety.) Instead, make transformIndexConstraint() generate ALTER TABLE SET NOT NULL subcommands to be executed ahead of the ADD PRIMARY KEY operation in every case where it can't force the column to be created already-not-null. This requires only minor surgery in parse_utilcmd.c, and it makes for a much more satisfying spec for transformIndexConstraint(): it's no longer having to take it on faith that someone else will handle addition of NOT NULL constraints. To make that work, we have to move the execution of AT_SetNotNull into an ALTER pass that executes ahead of AT_PASS_ADD_INDEX. I moved it to AT_PASS_COL_ATTRS, and put that after AT_PASS_ADD_COL to avoid failure when the column is being added in the same command. This incidentally fixes a bug in the only previous usage of AT_PASS_COL_ATTRS, for AT_SetIdentity: it didn't work either for a newly-added column. Playing around with this exposed a separate bug in ALTER TABLE ONLY ... ADD PRIMARY KEY for partitioned tables. The intent of the ONLY modifier in that context is to prevent doing anything that would require holding lock for a long time --- but the implied SET NOT NULL would recurse to the child partitions, and do an expensive validation scan for any child where the column(s) were not already NOT NULL. To fix that, invent a new ALTER subcommand AT_CheckNotNull that just insists that a child column be already NOT NULL, and apply that, not AT_SetNotNull, when recursing to children in this scenario. This results in a slightly laxer definition of ALTER TABLE ONLY ... SET NOT NULL for partitioned tables, too: that command will now work as long as all children are already NOT NULL, whereas before it just threw up its hands if there were any partitions. In passing, clean up the API of generateClonedIndexStmt(): remove a useless argument, ensure that the output argument is not left undefined, update the header comment. A small side effect of this change is that no-such-column errors in ALTER TABLE ADD PRIMARY KEY now produce a different message that includes the table name, because they are now detected by the SET NOT NULL step which has historically worded its error that way. That seems fine to me, so I didn't make any effort to avoid the wording change. The basic bug #15580 is of very long standing, and these other bugs aren't new in v12 either. However, this is a pretty significant change in the way ALTER TABLE ADD PRIMARY KEY works. On balance it seems best not to back-patch, at least not till we get some more confidence that this patch has no new bugs. Patch by me, but thanks to Jie Zhang for a preliminary version. Discussion: https://postgr.es/m/15580-d1a6de5a3d65da51@postgresql.org Discussion: https://postgr.es/m/1396E95157071C4EBBA51892C5368521017F2E6E63@G08CNEXMBPEKD02.g08.fujitsu.local
2019-04-23 18:25:27 +02:00
List *notnullcmds = NIL;
ListCell *lc;
index = makeNode(IndexStmt);
index->unique = (constraint->contype != CONSTR_EXCLUSION);
index->primary = (constraint->contype == CONSTR_PRIMARY);
if (index->primary)
{
if (cxt->pkey != NULL)
ereport(ERROR,
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
errmsg("multiple primary keys for table \"%s\" are not allowed",
cxt->relation->relname),
parser_errposition(cxt->pstate, constraint->location)));
cxt->pkey = index;
/*
* In ALTER TABLE case, a primary index might already exist, but
* DefineIndex will check for it.
*/
}
index->nulls_not_distinct = constraint->nulls_not_distinct;
index->isconstraint = true;
index->deferrable = constraint->deferrable;
index->initdeferred = constraint->initdeferred;
if (constraint->conname != NULL)
index->idxname = pstrdup(constraint->conname);
else
index->idxname = NULL; /* DefineIndex will choose name */
index->relation = cxt->relation;
index->accessMethod = constraint->access_method ? constraint->access_method : DEFAULT_INDEX_TYPE;
index->options = constraint->options;
index->tableSpace = constraint->indexspace;
index->whereClause = constraint->where_clause;
index->indexParams = NIL;
index->indexIncludingParams = NIL;
index->excludeOpNames = NIL;
index->idxcomment = NULL;
index->indexOid = InvalidOid;
Change internal RelFileNode references to RelFileNumber or RelFileLocator. We have been using the term RelFileNode to refer to either (1) the integer that is used to name the sequence of files for a certain relation within the directory set aside for that tablespace/database combination; or (2) that value plus the OIDs of the tablespace and database; or occasionally (3) the whole series of files created for a relation based on those values. Using the same name for more than one thing is confusing. Replace RelFileNode with RelFileNumber when we're talking about just the single number, i.e. (1) from above, and with RelFileLocator when we're talking about all the things that are needed to locate a relation's files on disk, i.e. (2) from above. In the places where we refer to (3) as a relfilenode, instead refer to "relation storage". Since there is a ton of SQL code in the world that knows about pg_class.relfilenode, don't change the name of that column, or of other SQL-facing things that derive their name from it. On the other hand, do adjust closely-related internal terminology. For example, the structure member names dbNode and spcNode appear to be derived from the fact that the structure itself was called RelFileNode, so change those to dbOid and spcOid. Likewise, various variables with names like rnode and relnode get renamed appropriately, according to how they're being used in context. Hopefully, this is clearer than before. It is also preparation for future patches that intend to widen the relfilenumber fields from its current width of 32 bits. Variables that store a relfilenumber are now declared as type RelFileNumber rather than type Oid; right now, these are the same, but that can now more easily be changed. Dilip Kumar, per an idea from me. Reviewed also by Andres Freund. I fixed some whitespace issues, changed a couple of words in a comment, and made one other minor correction. Discussion: http://postgr.es/m/CA+TgmoamOtXbVAQf9hWFzonUo6bhhjS6toZQd7HZ-pmojtAmag@mail.gmail.com Discussion: http://postgr.es/m/CA+Tgmobp7+7kmi4gkq7Y+4AM9fTvL+O1oQ4-5gFTT+6Ng-dQ=g@mail.gmail.com Discussion: http://postgr.es/m/CAFiTN-vTe79M8uDH1yprOU64MNFE+R3ODRuA+JWf27JbhY4hJw@mail.gmail.com
2022-07-06 17:39:09 +02:00
index->oldNumber = InvalidRelFileNumber;
Skip WAL for new relfilenodes, under wal_level=minimal. Until now, only selected bulk operations (e.g. COPY) did this. If a given relfilenode received both a WAL-skipping COPY and a WAL-logged operation (e.g. INSERT), recovery could lose tuples from the COPY. See src/backend/access/transam/README section "Skipping WAL for New RelFileNode" for the new coding rules. Maintainers of table access methods should examine that section. To maintain data durability, just before commit, we choose between an fsync of the relfilenode and copying its contents to WAL. A new GUC, wal_skip_threshold, guides that choice. If this change slows a workload that creates small, permanent relfilenodes under wal_level=minimal, try adjusting wal_skip_threshold. Users setting a timeout on COMMIT may need to adjust that timeout, and log_min_duration_statement analysis will reflect time consumption moving to COMMIT from commands like COPY. Internally, this requires a reliable determination of whether RollbackAndReleaseCurrentSubTransaction() would unlink a relation's current relfilenode. Introduce rd_firstRelfilenodeSubid. Amend the specification of rd_createSubid such that the field is zero when a new rel has an old rd_node. Make relcache.c retain entries for certain dropped relations until end of transaction. Bump XLOG_PAGE_MAGIC, since this introduces XLOG_GIST_ASSIGN_LSN. Future servers accept older WAL, so this bump is discretionary. Kyotaro Horiguchi, reviewed (in earlier, similar versions) by Robert Haas. Heikki Linnakangas and Michael Paquier implemented earlier designs that materially clarified the problem. Reviewed, in earlier designs, by Andrew Dunstan, Andres Freund, Alvaro Herrera, Tom Lane, Fujii Masao, and Simon Riggs. Reported by Martijn van Oosterhout. Discussion: https://postgr.es/m/20150702220524.GA9392@svana.org
2020-04-04 21:25:34 +02:00
index->oldCreateSubid = InvalidSubTransactionId;
Change internal RelFileNode references to RelFileNumber or RelFileLocator. We have been using the term RelFileNode to refer to either (1) the integer that is used to name the sequence of files for a certain relation within the directory set aside for that tablespace/database combination; or (2) that value plus the OIDs of the tablespace and database; or occasionally (3) the whole series of files created for a relation based on those values. Using the same name for more than one thing is confusing. Replace RelFileNode with RelFileNumber when we're talking about just the single number, i.e. (1) from above, and with RelFileLocator when we're talking about all the things that are needed to locate a relation's files on disk, i.e. (2) from above. In the places where we refer to (3) as a relfilenode, instead refer to "relation storage". Since there is a ton of SQL code in the world that knows about pg_class.relfilenode, don't change the name of that column, or of other SQL-facing things that derive their name from it. On the other hand, do adjust closely-related internal terminology. For example, the structure member names dbNode and spcNode appear to be derived from the fact that the structure itself was called RelFileNode, so change those to dbOid and spcOid. Likewise, various variables with names like rnode and relnode get renamed appropriately, according to how they're being used in context. Hopefully, this is clearer than before. It is also preparation for future patches that intend to widen the relfilenumber fields from its current width of 32 bits. Variables that store a relfilenumber are now declared as type RelFileNumber rather than type Oid; right now, these are the same, but that can now more easily be changed. Dilip Kumar, per an idea from me. Reviewed also by Andres Freund. I fixed some whitespace issues, changed a couple of words in a comment, and made one other minor correction. Discussion: http://postgr.es/m/CA+TgmoamOtXbVAQf9hWFzonUo6bhhjS6toZQd7HZ-pmojtAmag@mail.gmail.com Discussion: http://postgr.es/m/CA+Tgmobp7+7kmi4gkq7Y+4AM9fTvL+O1oQ4-5gFTT+6Ng-dQ=g@mail.gmail.com Discussion: http://postgr.es/m/CAFiTN-vTe79M8uDH1yprOU64MNFE+R3ODRuA+JWf27JbhY4hJw@mail.gmail.com
2022-07-06 17:39:09 +02:00
index->oldFirstRelfilelocatorSubid = InvalidSubTransactionId;
Get rid of multiple applications of transformExpr() to the same tree. transformExpr() has for many years had provisions to do nothing when applied to an already-transformed expression tree. However, this was always ugly and of dubious reliability, so we'd be much better off without it. The primary historical reason for it was that gram.y sometimes returned multiple links to the same subexpression, which is no longer true as of my BETWEEN fixes. We'd also grown some lazy hacks in CREATE TABLE LIKE (failing to distinguish between raw and already-transformed index specifications) and one or two other places. This patch removes the need for and support for re-transforming already transformed expressions. The index case is dealt with by adding a flag to struct IndexStmt to indicate that it's already been transformed; which has some benefit anyway in that tablecmds.c can now Assert that transformation has happened rather than just assuming. The other main reason was some rather sloppy code for array type coercion, which can be fixed (and its performance improved too) by refactoring. I did leave transformJoinUsingClause() still constructing expressions containing untransformed operator nodes being applied to Vars, so that transformExpr() still has to allow Var inputs. But that's a much narrower, and safer, special case than before, since Vars will never appear in a raw parse tree, and they don't have any substructure to worry about. In passing fix some oversights in the patch that added CREATE INDEX IF NOT EXISTS (missing processing of IndexStmt.if_not_exists). These appear relatively harmless, but still sloppy coding practice.
2015-02-22 19:59:09 +01:00
index->transformed = false;
index->concurrent = false;
Get rid of multiple applications of transformExpr() to the same tree. transformExpr() has for many years had provisions to do nothing when applied to an already-transformed expression tree. However, this was always ugly and of dubious reliability, so we'd be much better off without it. The primary historical reason for it was that gram.y sometimes returned multiple links to the same subexpression, which is no longer true as of my BETWEEN fixes. We'd also grown some lazy hacks in CREATE TABLE LIKE (failing to distinguish between raw and already-transformed index specifications) and one or two other places. This patch removes the need for and support for re-transforming already transformed expressions. The index case is dealt with by adding a flag to struct IndexStmt to indicate that it's already been transformed; which has some benefit anyway in that tablecmds.c can now Assert that transformation has happened rather than just assuming. The other main reason was some rather sloppy code for array type coercion, which can be fixed (and its performance improved too) by refactoring. I did leave transformJoinUsingClause() still constructing expressions containing untransformed operator nodes being applied to Vars, so that transformExpr() still has to allow Var inputs. But that's a much narrower, and safer, special case than before, since Vars will never appear in a raw parse tree, and they don't have any substructure to worry about. In passing fix some oversights in the patch that added CREATE INDEX IF NOT EXISTS (missing processing of IndexStmt.if_not_exists). These appear relatively harmless, but still sloppy coding practice.
2015-02-22 19:59:09 +01:00
index->if_not_exists = false;
index->reset_default_tblspc = constraint->reset_default_tblspc;
/*
* If it's ALTER TABLE ADD CONSTRAINT USING INDEX, look up the index and
* verify it's usable, then extract the implied column name list. (We
* will not actually need the column name list at runtime, but we need it
* now to check for duplicate column entries below.)
*/
if (constraint->indexname != NULL)
{
char *index_name = constraint->indexname;
Relation heap_rel = cxt->rel;
Oid index_oid;
Relation index_rel;
Form_pg_index index_form;
oidvector *indclass;
Datum indclassDatum;
int i;
/* Grammar should not allow this with explicit column list */
Assert(constraint->keys == NIL);
/* Grammar should only allow PRIMARY and UNIQUE constraints */
Assert(constraint->contype == CONSTR_PRIMARY ||
constraint->contype == CONSTR_UNIQUE);
/* Must be ALTER, not CREATE, but grammar doesn't enforce that */
if (!cxt->isalter)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot use an existing index in CREATE TABLE"),
parser_errposition(cxt->pstate, constraint->location)));
/* Look for the index in the same schema as the table */
index_oid = get_relname_relid(index_name, RelationGetNamespace(heap_rel));
if (!OidIsValid(index_oid))
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_OBJECT),
errmsg("index \"%s\" does not exist", index_name),
parser_errposition(cxt->pstate, constraint->location)));
/* Open the index (this will throw an error if it is not an index) */
index_rel = index_open(index_oid, AccessShareLock);
index_form = index_rel->rd_index;
/* Check that it does not have an associated constraint already */
if (OidIsValid(get_index_constraint(index_oid)))
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
errmsg("index \"%s\" is already associated with a constraint",
index_name),
parser_errposition(cxt->pstate, constraint->location)));
/* Perform validity checks on the index */
if (index_form->indrelid != RelationGetRelid(heap_rel))
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
errmsg("index \"%s\" does not belong to table \"%s\"",
index_name, RelationGetRelationName(heap_rel)),
parser_errposition(cxt->pstate, constraint->location)));
if (!index_form->indisvalid)
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
errmsg("index \"%s\" is not valid", index_name),
parser_errposition(cxt->pstate, constraint->location)));
if (!index_form->indisunique)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("\"%s\" is not a unique index", index_name),
errdetail("Cannot create a primary key or unique constraint using such an index."),
parser_errposition(cxt->pstate, constraint->location)));
if (RelationGetIndexExpressions(index_rel) != NIL)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("index \"%s\" contains expressions", index_name),
errdetail("Cannot create a primary key or unique constraint using such an index."),
parser_errposition(cxt->pstate, constraint->location)));
if (RelationGetIndexPredicate(index_rel) != NIL)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("\"%s\" is a partial index", index_name),
errdetail("Cannot create a primary key or unique constraint using such an index."),
parser_errposition(cxt->pstate, constraint->location)));
/*
* It's probably unsafe to change a deferred index to non-deferred. (A
* non-constraint index couldn't be deferred anyway, so this case
* should never occur; no need to sweat, but let's check it.)
*/
if (!index_form->indimmediate && !constraint->deferrable)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("\"%s\" is a deferrable index", index_name),
errdetail("Cannot create a non-deferrable constraint using a deferrable index."),
parser_errposition(cxt->pstate, constraint->location)));
/*
* Insist on it being a btree. That's the only kind that supports
* uniqueness at the moment anyway; but we must have an index that
* exactly matches what you'd get from plain ADD CONSTRAINT syntax,
* else dump and reload will produce a different index (breaking
* pg_upgrade in particular).
*/
if (index_rel->rd_rel->relam != get_index_am_oid(DEFAULT_INDEX_TYPE, false))
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
2011-07-04 23:01:35 +02:00
errmsg("index \"%s\" is not a btree", index_name),
parser_errposition(cxt->pstate, constraint->location)));
/* Must get indclass the hard way */
indclassDatum = SysCacheGetAttrNotNull(INDEXRELID,
index_rel->rd_indextuple,
Anum_pg_index_indclass);
indclass = (oidvector *) DatumGetPointer(indclassDatum);
for (i = 0; i < index_form->indnatts; i++)
{
int16 attnum = index_form->indkey.values[i];
const FormData_pg_attribute *attform;
char *attname;
Oid defopclass;
/*
* We shouldn't see attnum == 0 here, since we already rejected
* expression indexes. If we do, SystemAttributeDefinition will
* throw an error.
*/
if (attnum > 0)
{
Assert(attnum <= heap_rel->rd_att->natts);
attform = TupleDescAttr(heap_rel->rd_att, attnum - 1);
}
else
Remove WITH OIDS support, change oid catalog column visibility. Previously tables declared WITH OIDS, including a significant fraction of the catalog tables, stored the oid column not as a normal column, but as part of the tuple header. This special column was not shown by default, which was somewhat odd, as it's often (consider e.g. pg_class.oid) one of the more important parts of a row. Neither pg_dump nor COPY included the contents of the oid column by default. The fact that the oid column was not an ordinary column necessitated a significant amount of special case code to support oid columns. That already was painful for the existing, but upcoming work aiming to make table storage pluggable, would have required expanding and duplicating that "specialness" significantly. WITH OIDS has been deprecated since 2005 (commit ff02d0a05280e0). Remove it. Removing includes: - CREATE TABLE and ALTER TABLE syntax for declaring the table to be WITH OIDS has been removed (WITH (oids[ = true]) will error out) - pg_dump does not support dumping tables declared WITH OIDS and will issue a warning when dumping one (and ignore the oid column). - restoring an pg_dump archive with pg_restore will warn when restoring a table with oid contents (and ignore the oid column) - COPY will refuse to load binary dump that includes oids. - pg_upgrade will error out when encountering tables declared WITH OIDS, they have to be altered to remove the oid column first. - Functionality to access the oid of the last inserted row (like plpgsql's RESULT_OID, spi's SPI_lastoid, ...) has been removed. The syntax for declaring a table WITHOUT OIDS (or WITH (oids = false) for CREATE TABLE) is still supported. While that requires a bit of support code, it seems unnecessary to break applications / dumps that do not use oids, and are explicit about not using them. The biggest user of WITH OID columns was postgres' catalog. This commit changes all 'magic' oid columns to be columns that are normally declared and stored. To reduce unnecessary query breakage all the newly added columns are still named 'oid', even if a table's column naming scheme would indicate 'reloid' or such. This obviously requires adapting a lot code, mostly replacing oid access via HeapTupleGetOid() with access to the underlying Form_pg_*->oid column. The bootstrap process now assigns oids for all oid columns in genbki.pl that do not have an explicit value (starting at the largest oid previously used), only oids assigned later by oids will be above FirstBootstrapObjectId. As the oid column now is a normal column the special bootstrap syntax for oids has been removed. Oids are not automatically assigned during insertion anymore, all backend code explicitly assigns oids with GetNewOidWithIndex(). For the rare case that insertions into the catalog via SQL are called for the new pg_nextoid() function can be used (which only works on catalog tables). The fact that oid columns on system tables are now normal columns means that they will be included in the set of columns expanded by * (i.e. SELECT * FROM pg_class will now include the table's oid, previously it did not). It'd not technically be hard to hide oid column by default, but that'd mean confusing behavior would either have to be carried forward forever, or it'd cause breakage down the line. While it's not unlikely that further adjustments are needed, the scope/invasiveness of the patch makes it worthwhile to get merge this now. It's painful to maintain externally, too complicated to commit after the code code freeze, and a dependency of a number of other patches. Catversion bump, for obvious reasons. Author: Andres Freund, with contributions by John Naylor Discussion: https://postgr.es/m/20180930034810.ywp2c7awz7opzcfr@alap3.anarazel.de
2018-11-21 00:36:57 +01:00
attform = SystemAttributeDefinition(attnum);
attname = pstrdup(NameStr(attform->attname));
if (i < index_form->indnkeyatts)
{
/*
Disallow non-default collation in ADD PRIMARY KEY/UNIQUE USING INDEX. When creating a uniqueness constraint using a pre-existing index, we have always required that the index have the same properties you'd get if you just let a new index get built. However, when collations were added, we forgot to add the index's collation to that check. It's hard to trip over this without intentionally trying to break it: you'd have to explicitly specify a different collation in CREATE INDEX, then convert it to a pkey or unique constraint. Still, if you did that, pg_dump would emit a script that fails to reproduce the index's collation. The main practical problem is that after a pg_upgrade the index would be corrupt, because its actual physical order wouldn't match what pg_index says. A more theoretical issue, which is new as of v12, is that if you create the index with a nondeterministic collation then it wouldn't be enforcing the normal notion of uniqueness, causing the constraint to mean something different from a normally-created constraint. To fix, just add collation to the conditions checked for index acceptability in ADD PRIMARY KEY/UNIQUE USING INDEX. We won't try to clean up after anybody who's already created such a situation; it seems improbable enough to not be worth the effort involved. (If you do get into trouble, a REINDEX should be enough to fix it.) In principle this is a long-standing bug, but I chose not to back-patch --- the odds of causing trouble seem about as great as the odds of preventing it, and both risks are very low anyway. Per report from Alexey Bashtanov, though this is not his preferred fix. Discussion: https://postgr.es/m/b05ce36a-cefb-ca5e-b386-a400535b1c0b@imap.cc
2019-12-06 17:25:09 +01:00
* Insist on default opclass, collation, and sort options.
* While the index would still work as a constraint with
* non-default settings, it might not provide exactly the same
* uniqueness semantics as you'd get from a normally-created
* constraint; and there's also the dump/reload problem
* mentioned above.
*/
Implement operator class parameters PostgreSQL provides set of template index access methods, where opclasses have much freedom in the semantics of indexing. These index AMs are GiST, GIN, SP-GiST and BRIN. There opclasses define representation of keys, operations on them and supported search strategies. So, it's natural that opclasses may be faced some tradeoffs, which require user-side decision. This commit implements opclass parameters allowing users to set some values, which tell opclass how to index the particular dataset. This commit doesn't introduce new storage in system catalog. Instead it uses pg_attribute.attoptions, which is used for table column storage options but unused for index attributes. In order to evade changing signature of each opclass support function, we implement unified way to pass options to opclass support functions. Options are set to fn_expr as the constant bytea expression. It's possible due to the fact that opclass support functions are executed outside of expressions, so fn_expr is unused for them. This commit comes with some examples of opclass options usage. We parametrize signature length in GiST. That applies to multiple opclasses: tsvector_ops, gist__intbig_ops, gist_ltree_ops, gist__ltree_ops, gist_trgm_ops and gist_hstore_ops. Also we parametrize maximum number of integer ranges for gist__int_ops. However, the main future usage of this feature is expected to be json, where users would be able to specify which way to index particular json parts. Catversion is bumped. Discussion: https://postgr.es/m/d22c3a18-31c7-1879-fc11-4c1ce2f5e5af%40postgrespro.ru Author: Nikita Glukhov, revised by me Reviwed-by: Nikolay Shaplov, Robert Haas, Tom Lane, Tomas Vondra, Alvaro Herrera
2020-03-30 18:17:11 +02:00
Datum attoptions =
get_attoptions(RelationGetRelid(index_rel), i + 1);
Implement operator class parameters PostgreSQL provides set of template index access methods, where opclasses have much freedom in the semantics of indexing. These index AMs are GiST, GIN, SP-GiST and BRIN. There opclasses define representation of keys, operations on them and supported search strategies. So, it's natural that opclasses may be faced some tradeoffs, which require user-side decision. This commit implements opclass parameters allowing users to set some values, which tell opclass how to index the particular dataset. This commit doesn't introduce new storage in system catalog. Instead it uses pg_attribute.attoptions, which is used for table column storage options but unused for index attributes. In order to evade changing signature of each opclass support function, we implement unified way to pass options to opclass support functions. Options are set to fn_expr as the constant bytea expression. It's possible due to the fact that opclass support functions are executed outside of expressions, so fn_expr is unused for them. This commit comes with some examples of opclass options usage. We parametrize signature length in GiST. That applies to multiple opclasses: tsvector_ops, gist__intbig_ops, gist_ltree_ops, gist__ltree_ops, gist_trgm_ops and gist_hstore_ops. Also we parametrize maximum number of integer ranges for gist__int_ops. However, the main future usage of this feature is expected to be json, where users would be able to specify which way to index particular json parts. Catversion is bumped. Discussion: https://postgr.es/m/d22c3a18-31c7-1879-fc11-4c1ce2f5e5af%40postgrespro.ru Author: Nikita Glukhov, revised by me Reviwed-by: Nikolay Shaplov, Robert Haas, Tom Lane, Tomas Vondra, Alvaro Herrera
2020-03-30 18:17:11 +02:00
defopclass = GetDefaultOpClass(attform->atttypid,
index_rel->rd_rel->relam);
if (indclass->values[i] != defopclass ||
Disallow non-default collation in ADD PRIMARY KEY/UNIQUE USING INDEX. When creating a uniqueness constraint using a pre-existing index, we have always required that the index have the same properties you'd get if you just let a new index get built. However, when collations were added, we forgot to add the index's collation to that check. It's hard to trip over this without intentionally trying to break it: you'd have to explicitly specify a different collation in CREATE INDEX, then convert it to a pkey or unique constraint. Still, if you did that, pg_dump would emit a script that fails to reproduce the index's collation. The main practical problem is that after a pg_upgrade the index would be corrupt, because its actual physical order wouldn't match what pg_index says. A more theoretical issue, which is new as of v12, is that if you create the index with a nondeterministic collation then it wouldn't be enforcing the normal notion of uniqueness, causing the constraint to mean something different from a normally-created constraint. To fix, just add collation to the conditions checked for index acceptability in ADD PRIMARY KEY/UNIQUE USING INDEX. We won't try to clean up after anybody who's already created such a situation; it seems improbable enough to not be worth the effort involved. (If you do get into trouble, a REINDEX should be enough to fix it.) In principle this is a long-standing bug, but I chose not to back-patch --- the odds of causing trouble seem about as great as the odds of preventing it, and both risks are very low anyway. Per report from Alexey Bashtanov, though this is not his preferred fix. Discussion: https://postgr.es/m/b05ce36a-cefb-ca5e-b386-a400535b1c0b@imap.cc
2019-12-06 17:25:09 +01:00
attform->attcollation != index_rel->rd_indcollation[i] ||
Implement operator class parameters PostgreSQL provides set of template index access methods, where opclasses have much freedom in the semantics of indexing. These index AMs are GiST, GIN, SP-GiST and BRIN. There opclasses define representation of keys, operations on them and supported search strategies. So, it's natural that opclasses may be faced some tradeoffs, which require user-side decision. This commit implements opclass parameters allowing users to set some values, which tell opclass how to index the particular dataset. This commit doesn't introduce new storage in system catalog. Instead it uses pg_attribute.attoptions, which is used for table column storage options but unused for index attributes. In order to evade changing signature of each opclass support function, we implement unified way to pass options to opclass support functions. Options are set to fn_expr as the constant bytea expression. It's possible due to the fact that opclass support functions are executed outside of expressions, so fn_expr is unused for them. This commit comes with some examples of opclass options usage. We parametrize signature length in GiST. That applies to multiple opclasses: tsvector_ops, gist__intbig_ops, gist_ltree_ops, gist__ltree_ops, gist_trgm_ops and gist_hstore_ops. Also we parametrize maximum number of integer ranges for gist__int_ops. However, the main future usage of this feature is expected to be json, where users would be able to specify which way to index particular json parts. Catversion is bumped. Discussion: https://postgr.es/m/d22c3a18-31c7-1879-fc11-4c1ce2f5e5af%40postgrespro.ru Author: Nikita Glukhov, revised by me Reviwed-by: Nikolay Shaplov, Robert Haas, Tom Lane, Tomas Vondra, Alvaro Herrera
2020-03-30 18:17:11 +02:00
attoptions != (Datum) 0 ||
index_rel->rd_indoption[i] != 0)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
2018-05-18 23:17:57 +02:00
errmsg("index \"%s\" column number %d does not have default sorting behavior", index_name, i + 1),
errdetail("Cannot create a primary key or unique constraint using such an index."),
parser_errposition(cxt->pstate, constraint->location)));
constraint->keys = lappend(constraint->keys, makeString(attname));
}
else
constraint->including = lappend(constraint->including, makeString(attname));
}
/* Close the index relation but keep the lock */
relation_close(index_rel, NoLock);
index->indexOid = index_oid;
}
/*
* If it's an EXCLUDE constraint, the grammar returns a list of pairs of
* IndexElems and operator names. We have to break that apart into
* separate lists.
*/
if (constraint->contype == CONSTR_EXCLUSION)
{
foreach(lc, constraint->exclusions)
{
List *pair = (List *) lfirst(lc);
IndexElem *elem;
List *opname;
Assert(list_length(pair) == 2);
elem = linitial_node(IndexElem, pair);
opname = lsecond_node(List, pair);
index->indexParams = lappend(index->indexParams, elem);
index->excludeOpNames = lappend(index->excludeOpNames, opname);
}
}
/*
* For UNIQUE and PRIMARY KEY, we just have a list of column names.
*
* Make sure referenced keys exist. If we are making a PRIMARY KEY index,
Avoid order-of-execution problems with ALTER TABLE ADD PRIMARY KEY. Up to now, DefineIndex() was responsible for adding attnotnull constraints to the columns of a primary key, in any case where it hadn't been convenient for transformIndexConstraint() to mark those columns as is_not_null. It (or rather its minion index_check_primary_key) did this by executing an ALTER TABLE SET NOT NULL command for the target table. The trouble with this solution is that if we're creating the index due to ALTER TABLE ADD PRIMARY KEY, and the outer ALTER TABLE has additional sub-commands, the inner ALTER TABLE's operations executed at the wrong time with respect to the outer ALTER TABLE's operations. In particular, the inner ALTER would perform a validation scan at a point where the table's storage might be inconsistent with its catalog entries. (This is on the hairy edge of being a security problem, but AFAICS it isn't one because the inner scan would only be interested in the tuples' null bitmaps.) This can result in unexpected failures, such as the one seen in bug #15580 from Allison Kaptur. To fix, let's remove the attempt to do SET NOT NULL from DefineIndex(), reducing index_check_primary_key's role to verifying that the columns are already not null. (It shouldn't ever see such a case, but it seems wise to keep the check for safety.) Instead, make transformIndexConstraint() generate ALTER TABLE SET NOT NULL subcommands to be executed ahead of the ADD PRIMARY KEY operation in every case where it can't force the column to be created already-not-null. This requires only minor surgery in parse_utilcmd.c, and it makes for a much more satisfying spec for transformIndexConstraint(): it's no longer having to take it on faith that someone else will handle addition of NOT NULL constraints. To make that work, we have to move the execution of AT_SetNotNull into an ALTER pass that executes ahead of AT_PASS_ADD_INDEX. I moved it to AT_PASS_COL_ATTRS, and put that after AT_PASS_ADD_COL to avoid failure when the column is being added in the same command. This incidentally fixes a bug in the only previous usage of AT_PASS_COL_ATTRS, for AT_SetIdentity: it didn't work either for a newly-added column. Playing around with this exposed a separate bug in ALTER TABLE ONLY ... ADD PRIMARY KEY for partitioned tables. The intent of the ONLY modifier in that context is to prevent doing anything that would require holding lock for a long time --- but the implied SET NOT NULL would recurse to the child partitions, and do an expensive validation scan for any child where the column(s) were not already NOT NULL. To fix that, invent a new ALTER subcommand AT_CheckNotNull that just insists that a child column be already NOT NULL, and apply that, not AT_SetNotNull, when recursing to children in this scenario. This results in a slightly laxer definition of ALTER TABLE ONLY ... SET NOT NULL for partitioned tables, too: that command will now work as long as all children are already NOT NULL, whereas before it just threw up its hands if there were any partitions. In passing, clean up the API of generateClonedIndexStmt(): remove a useless argument, ensure that the output argument is not left undefined, update the header comment. A small side effect of this change is that no-such-column errors in ALTER TABLE ADD PRIMARY KEY now produce a different message that includes the table name, because they are now detected by the SET NOT NULL step which has historically worded its error that way. That seems fine to me, so I didn't make any effort to avoid the wording change. The basic bug #15580 is of very long standing, and these other bugs aren't new in v12 either. However, this is a pretty significant change in the way ALTER TABLE ADD PRIMARY KEY works. On balance it seems best not to back-patch, at least not till we get some more confidence that this patch has no new bugs. Patch by me, but thanks to Jie Zhang for a preliminary version. Discussion: https://postgr.es/m/15580-d1a6de5a3d65da51@postgresql.org Discussion: https://postgr.es/m/1396E95157071C4EBBA51892C5368521017F2E6E63@G08CNEXMBPEKD02.g08.fujitsu.local
2019-04-23 18:25:27 +02:00
* also make sure they are NOT NULL.
*/
else
{
foreach(lc, constraint->keys)
{
char *key = strVal(lfirst(lc));
bool found = false;
bool forced_not_null = false;
ColumnDef *column = NULL;
ListCell *columns;
IndexElem *iparam;
Avoid order-of-execution problems with ALTER TABLE ADD PRIMARY KEY. Up to now, DefineIndex() was responsible for adding attnotnull constraints to the columns of a primary key, in any case where it hadn't been convenient for transformIndexConstraint() to mark those columns as is_not_null. It (or rather its minion index_check_primary_key) did this by executing an ALTER TABLE SET NOT NULL command for the target table. The trouble with this solution is that if we're creating the index due to ALTER TABLE ADD PRIMARY KEY, and the outer ALTER TABLE has additional sub-commands, the inner ALTER TABLE's operations executed at the wrong time with respect to the outer ALTER TABLE's operations. In particular, the inner ALTER would perform a validation scan at a point where the table's storage might be inconsistent with its catalog entries. (This is on the hairy edge of being a security problem, but AFAICS it isn't one because the inner scan would only be interested in the tuples' null bitmaps.) This can result in unexpected failures, such as the one seen in bug #15580 from Allison Kaptur. To fix, let's remove the attempt to do SET NOT NULL from DefineIndex(), reducing index_check_primary_key's role to verifying that the columns are already not null. (It shouldn't ever see such a case, but it seems wise to keep the check for safety.) Instead, make transformIndexConstraint() generate ALTER TABLE SET NOT NULL subcommands to be executed ahead of the ADD PRIMARY KEY operation in every case where it can't force the column to be created already-not-null. This requires only minor surgery in parse_utilcmd.c, and it makes for a much more satisfying spec for transformIndexConstraint(): it's no longer having to take it on faith that someone else will handle addition of NOT NULL constraints. To make that work, we have to move the execution of AT_SetNotNull into an ALTER pass that executes ahead of AT_PASS_ADD_INDEX. I moved it to AT_PASS_COL_ATTRS, and put that after AT_PASS_ADD_COL to avoid failure when the column is being added in the same command. This incidentally fixes a bug in the only previous usage of AT_PASS_COL_ATTRS, for AT_SetIdentity: it didn't work either for a newly-added column. Playing around with this exposed a separate bug in ALTER TABLE ONLY ... ADD PRIMARY KEY for partitioned tables. The intent of the ONLY modifier in that context is to prevent doing anything that would require holding lock for a long time --- but the implied SET NOT NULL would recurse to the child partitions, and do an expensive validation scan for any child where the column(s) were not already NOT NULL. To fix that, invent a new ALTER subcommand AT_CheckNotNull that just insists that a child column be already NOT NULL, and apply that, not AT_SetNotNull, when recursing to children in this scenario. This results in a slightly laxer definition of ALTER TABLE ONLY ... SET NOT NULL for partitioned tables, too: that command will now work as long as all children are already NOT NULL, whereas before it just threw up its hands if there were any partitions. In passing, clean up the API of generateClonedIndexStmt(): remove a useless argument, ensure that the output argument is not left undefined, update the header comment. A small side effect of this change is that no-such-column errors in ALTER TABLE ADD PRIMARY KEY now produce a different message that includes the table name, because they are now detected by the SET NOT NULL step which has historically worded its error that way. That seems fine to me, so I didn't make any effort to avoid the wording change. The basic bug #15580 is of very long standing, and these other bugs aren't new in v12 either. However, this is a pretty significant change in the way ALTER TABLE ADD PRIMARY KEY works. On balance it seems best not to back-patch, at least not till we get some more confidence that this patch has no new bugs. Patch by me, but thanks to Jie Zhang for a preliminary version. Discussion: https://postgr.es/m/15580-d1a6de5a3d65da51@postgresql.org Discussion: https://postgr.es/m/1396E95157071C4EBBA51892C5368521017F2E6E63@G08CNEXMBPEKD02.g08.fujitsu.local
2019-04-23 18:25:27 +02:00
/* Make sure referenced column exists. */
foreach(columns, cxt->columns)
{
column = lfirst_node(ColumnDef, columns);
if (strcmp(column->colname, key) == 0)
{
found = true;
break;
}
}
if (found)
{
Avoid order-of-execution problems with ALTER TABLE ADD PRIMARY KEY. Up to now, DefineIndex() was responsible for adding attnotnull constraints to the columns of a primary key, in any case where it hadn't been convenient for transformIndexConstraint() to mark those columns as is_not_null. It (or rather its minion index_check_primary_key) did this by executing an ALTER TABLE SET NOT NULL command for the target table. The trouble with this solution is that if we're creating the index due to ALTER TABLE ADD PRIMARY KEY, and the outer ALTER TABLE has additional sub-commands, the inner ALTER TABLE's operations executed at the wrong time with respect to the outer ALTER TABLE's operations. In particular, the inner ALTER would perform a validation scan at a point where the table's storage might be inconsistent with its catalog entries. (This is on the hairy edge of being a security problem, but AFAICS it isn't one because the inner scan would only be interested in the tuples' null bitmaps.) This can result in unexpected failures, such as the one seen in bug #15580 from Allison Kaptur. To fix, let's remove the attempt to do SET NOT NULL from DefineIndex(), reducing index_check_primary_key's role to verifying that the columns are already not null. (It shouldn't ever see such a case, but it seems wise to keep the check for safety.) Instead, make transformIndexConstraint() generate ALTER TABLE SET NOT NULL subcommands to be executed ahead of the ADD PRIMARY KEY operation in every case where it can't force the column to be created already-not-null. This requires only minor surgery in parse_utilcmd.c, and it makes for a much more satisfying spec for transformIndexConstraint(): it's no longer having to take it on faith that someone else will handle addition of NOT NULL constraints. To make that work, we have to move the execution of AT_SetNotNull into an ALTER pass that executes ahead of AT_PASS_ADD_INDEX. I moved it to AT_PASS_COL_ATTRS, and put that after AT_PASS_ADD_COL to avoid failure when the column is being added in the same command. This incidentally fixes a bug in the only previous usage of AT_PASS_COL_ATTRS, for AT_SetIdentity: it didn't work either for a newly-added column. Playing around with this exposed a separate bug in ALTER TABLE ONLY ... ADD PRIMARY KEY for partitioned tables. The intent of the ONLY modifier in that context is to prevent doing anything that would require holding lock for a long time --- but the implied SET NOT NULL would recurse to the child partitions, and do an expensive validation scan for any child where the column(s) were not already NOT NULL. To fix that, invent a new ALTER subcommand AT_CheckNotNull that just insists that a child column be already NOT NULL, and apply that, not AT_SetNotNull, when recursing to children in this scenario. This results in a slightly laxer definition of ALTER TABLE ONLY ... SET NOT NULL for partitioned tables, too: that command will now work as long as all children are already NOT NULL, whereas before it just threw up its hands if there were any partitions. In passing, clean up the API of generateClonedIndexStmt(): remove a useless argument, ensure that the output argument is not left undefined, update the header comment. A small side effect of this change is that no-such-column errors in ALTER TABLE ADD PRIMARY KEY now produce a different message that includes the table name, because they are now detected by the SET NOT NULL step which has historically worded its error that way. That seems fine to me, so I didn't make any effort to avoid the wording change. The basic bug #15580 is of very long standing, and these other bugs aren't new in v12 either. However, this is a pretty significant change in the way ALTER TABLE ADD PRIMARY KEY works. On balance it seems best not to back-patch, at least not till we get some more confidence that this patch has no new bugs. Patch by me, but thanks to Jie Zhang for a preliminary version. Discussion: https://postgr.es/m/15580-d1a6de5a3d65da51@postgresql.org Discussion: https://postgr.es/m/1396E95157071C4EBBA51892C5368521017F2E6E63@G08CNEXMBPEKD02.g08.fujitsu.local
2019-04-23 18:25:27 +02:00
/*
* column is defined in the new table. For PRIMARY KEY, we
* can apply the NOT NULL constraint cheaply here ... unless
* the column is marked is_from_type, in which case marking it
* here would be ineffective (see MergeAttributes).
Avoid order-of-execution problems with ALTER TABLE ADD PRIMARY KEY. Up to now, DefineIndex() was responsible for adding attnotnull constraints to the columns of a primary key, in any case where it hadn't been convenient for transformIndexConstraint() to mark those columns as is_not_null. It (or rather its minion index_check_primary_key) did this by executing an ALTER TABLE SET NOT NULL command for the target table. The trouble with this solution is that if we're creating the index due to ALTER TABLE ADD PRIMARY KEY, and the outer ALTER TABLE has additional sub-commands, the inner ALTER TABLE's operations executed at the wrong time with respect to the outer ALTER TABLE's operations. In particular, the inner ALTER would perform a validation scan at a point where the table's storage might be inconsistent with its catalog entries. (This is on the hairy edge of being a security problem, but AFAICS it isn't one because the inner scan would only be interested in the tuples' null bitmaps.) This can result in unexpected failures, such as the one seen in bug #15580 from Allison Kaptur. To fix, let's remove the attempt to do SET NOT NULL from DefineIndex(), reducing index_check_primary_key's role to verifying that the columns are already not null. (It shouldn't ever see such a case, but it seems wise to keep the check for safety.) Instead, make transformIndexConstraint() generate ALTER TABLE SET NOT NULL subcommands to be executed ahead of the ADD PRIMARY KEY operation in every case where it can't force the column to be created already-not-null. This requires only minor surgery in parse_utilcmd.c, and it makes for a much more satisfying spec for transformIndexConstraint(): it's no longer having to take it on faith that someone else will handle addition of NOT NULL constraints. To make that work, we have to move the execution of AT_SetNotNull into an ALTER pass that executes ahead of AT_PASS_ADD_INDEX. I moved it to AT_PASS_COL_ATTRS, and put that after AT_PASS_ADD_COL to avoid failure when the column is being added in the same command. This incidentally fixes a bug in the only previous usage of AT_PASS_COL_ATTRS, for AT_SetIdentity: it didn't work either for a newly-added column. Playing around with this exposed a separate bug in ALTER TABLE ONLY ... ADD PRIMARY KEY for partitioned tables. The intent of the ONLY modifier in that context is to prevent doing anything that would require holding lock for a long time --- but the implied SET NOT NULL would recurse to the child partitions, and do an expensive validation scan for any child where the column(s) were not already NOT NULL. To fix that, invent a new ALTER subcommand AT_CheckNotNull that just insists that a child column be already NOT NULL, and apply that, not AT_SetNotNull, when recursing to children in this scenario. This results in a slightly laxer definition of ALTER TABLE ONLY ... SET NOT NULL for partitioned tables, too: that command will now work as long as all children are already NOT NULL, whereas before it just threw up its hands if there were any partitions. In passing, clean up the API of generateClonedIndexStmt(): remove a useless argument, ensure that the output argument is not left undefined, update the header comment. A small side effect of this change is that no-such-column errors in ALTER TABLE ADD PRIMARY KEY now produce a different message that includes the table name, because they are now detected by the SET NOT NULL step which has historically worded its error that way. That seems fine to me, so I didn't make any effort to avoid the wording change. The basic bug #15580 is of very long standing, and these other bugs aren't new in v12 either. However, this is a pretty significant change in the way ALTER TABLE ADD PRIMARY KEY works. On balance it seems best not to back-patch, at least not till we get some more confidence that this patch has no new bugs. Patch by me, but thanks to Jie Zhang for a preliminary version. Discussion: https://postgr.es/m/15580-d1a6de5a3d65da51@postgresql.org Discussion: https://postgr.es/m/1396E95157071C4EBBA51892C5368521017F2E6E63@G08CNEXMBPEKD02.g08.fujitsu.local
2019-04-23 18:25:27 +02:00
*/
if (constraint->contype == CONSTR_PRIMARY &&
!column->is_from_type)
{
column->is_not_null = true;
forced_not_null = true;
Avoid order-of-execution problems with ALTER TABLE ADD PRIMARY KEY. Up to now, DefineIndex() was responsible for adding attnotnull constraints to the columns of a primary key, in any case where it hadn't been convenient for transformIndexConstraint() to mark those columns as is_not_null. It (or rather its minion index_check_primary_key) did this by executing an ALTER TABLE SET NOT NULL command for the target table. The trouble with this solution is that if we're creating the index due to ALTER TABLE ADD PRIMARY KEY, and the outer ALTER TABLE has additional sub-commands, the inner ALTER TABLE's operations executed at the wrong time with respect to the outer ALTER TABLE's operations. In particular, the inner ALTER would perform a validation scan at a point where the table's storage might be inconsistent with its catalog entries. (This is on the hairy edge of being a security problem, but AFAICS it isn't one because the inner scan would only be interested in the tuples' null bitmaps.) This can result in unexpected failures, such as the one seen in bug #15580 from Allison Kaptur. To fix, let's remove the attempt to do SET NOT NULL from DefineIndex(), reducing index_check_primary_key's role to verifying that the columns are already not null. (It shouldn't ever see such a case, but it seems wise to keep the check for safety.) Instead, make transformIndexConstraint() generate ALTER TABLE SET NOT NULL subcommands to be executed ahead of the ADD PRIMARY KEY operation in every case where it can't force the column to be created already-not-null. This requires only minor surgery in parse_utilcmd.c, and it makes for a much more satisfying spec for transformIndexConstraint(): it's no longer having to take it on faith that someone else will handle addition of NOT NULL constraints. To make that work, we have to move the execution of AT_SetNotNull into an ALTER pass that executes ahead of AT_PASS_ADD_INDEX. I moved it to AT_PASS_COL_ATTRS, and put that after AT_PASS_ADD_COL to avoid failure when the column is being added in the same command. This incidentally fixes a bug in the only previous usage of AT_PASS_COL_ATTRS, for AT_SetIdentity: it didn't work either for a newly-added column. Playing around with this exposed a separate bug in ALTER TABLE ONLY ... ADD PRIMARY KEY for partitioned tables. The intent of the ONLY modifier in that context is to prevent doing anything that would require holding lock for a long time --- but the implied SET NOT NULL would recurse to the child partitions, and do an expensive validation scan for any child where the column(s) were not already NOT NULL. To fix that, invent a new ALTER subcommand AT_CheckNotNull that just insists that a child column be already NOT NULL, and apply that, not AT_SetNotNull, when recursing to children in this scenario. This results in a slightly laxer definition of ALTER TABLE ONLY ... SET NOT NULL for partitioned tables, too: that command will now work as long as all children are already NOT NULL, whereas before it just threw up its hands if there were any partitions. In passing, clean up the API of generateClonedIndexStmt(): remove a useless argument, ensure that the output argument is not left undefined, update the header comment. A small side effect of this change is that no-such-column errors in ALTER TABLE ADD PRIMARY KEY now produce a different message that includes the table name, because they are now detected by the SET NOT NULL step which has historically worded its error that way. That seems fine to me, so I didn't make any effort to avoid the wording change. The basic bug #15580 is of very long standing, and these other bugs aren't new in v12 either. However, this is a pretty significant change in the way ALTER TABLE ADD PRIMARY KEY works. On balance it seems best not to back-patch, at least not till we get some more confidence that this patch has no new bugs. Patch by me, but thanks to Jie Zhang for a preliminary version. Discussion: https://postgr.es/m/15580-d1a6de5a3d65da51@postgresql.org Discussion: https://postgr.es/m/1396E95157071C4EBBA51892C5368521017F2E6E63@G08CNEXMBPEKD02.g08.fujitsu.local
2019-04-23 18:25:27 +02:00
}
}
Remove WITH OIDS support, change oid catalog column visibility. Previously tables declared WITH OIDS, including a significant fraction of the catalog tables, stored the oid column not as a normal column, but as part of the tuple header. This special column was not shown by default, which was somewhat odd, as it's often (consider e.g. pg_class.oid) one of the more important parts of a row. Neither pg_dump nor COPY included the contents of the oid column by default. The fact that the oid column was not an ordinary column necessitated a significant amount of special case code to support oid columns. That already was painful for the existing, but upcoming work aiming to make table storage pluggable, would have required expanding and duplicating that "specialness" significantly. WITH OIDS has been deprecated since 2005 (commit ff02d0a05280e0). Remove it. Removing includes: - CREATE TABLE and ALTER TABLE syntax for declaring the table to be WITH OIDS has been removed (WITH (oids[ = true]) will error out) - pg_dump does not support dumping tables declared WITH OIDS and will issue a warning when dumping one (and ignore the oid column). - restoring an pg_dump archive with pg_restore will warn when restoring a table with oid contents (and ignore the oid column) - COPY will refuse to load binary dump that includes oids. - pg_upgrade will error out when encountering tables declared WITH OIDS, they have to be altered to remove the oid column first. - Functionality to access the oid of the last inserted row (like plpgsql's RESULT_OID, spi's SPI_lastoid, ...) has been removed. The syntax for declaring a table WITHOUT OIDS (or WITH (oids = false) for CREATE TABLE) is still supported. While that requires a bit of support code, it seems unnecessary to break applications / dumps that do not use oids, and are explicit about not using them. The biggest user of WITH OID columns was postgres' catalog. This commit changes all 'magic' oid columns to be columns that are normally declared and stored. To reduce unnecessary query breakage all the newly added columns are still named 'oid', even if a table's column naming scheme would indicate 'reloid' or such. This obviously requires adapting a lot code, mostly replacing oid access via HeapTupleGetOid() with access to the underlying Form_pg_*->oid column. The bootstrap process now assigns oids for all oid columns in genbki.pl that do not have an explicit value (starting at the largest oid previously used), only oids assigned later by oids will be above FirstBootstrapObjectId. As the oid column now is a normal column the special bootstrap syntax for oids has been removed. Oids are not automatically assigned during insertion anymore, all backend code explicitly assigns oids with GetNewOidWithIndex(). For the rare case that insertions into the catalog via SQL are called for the new pg_nextoid() function can be used (which only works on catalog tables). The fact that oid columns on system tables are now normal columns means that they will be included in the set of columns expanded by * (i.e. SELECT * FROM pg_class will now include the table's oid, previously it did not). It'd not technically be hard to hide oid column by default, but that'd mean confusing behavior would either have to be carried forward forever, or it'd cause breakage down the line. While it's not unlikely that further adjustments are needed, the scope/invasiveness of the patch makes it worthwhile to get merge this now. It's painful to maintain externally, too complicated to commit after the code code freeze, and a dependency of a number of other patches. Catversion bump, for obvious reasons. Author: Andres Freund, with contributions by John Naylor Discussion: https://postgr.es/m/20180930034810.ywp2c7awz7opzcfr@alap3.anarazel.de
2018-11-21 00:36:57 +01:00
else if (SystemAttributeByName(key) != NULL)
{
/*
* column will be a system column in the new table, so accept
* it. System columns can't ever be null, so no need to worry
* about PRIMARY/NOT NULL constraint.
*/
found = true;
}
else if (cxt->inhRelations)
{
/* try inherited tables */
ListCell *inher;
foreach(inher, cxt->inhRelations)
{
RangeVar *inh = lfirst_node(RangeVar, inher);
Relation rel;
int count;
rel = table_openrv(inh, AccessShareLock);
/* check user requested inheritance from valid relkind */
if (rel->rd_rel->relkind != RELKIND_RELATION &&
rel->rd_rel->relkind != RELKIND_FOREIGN_TABLE &&
rel->rd_rel->relkind != RELKIND_PARTITIONED_TABLE)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("inherited relation \"%s\" is not a table or foreign table",
inh->relname)));
for (count = 0; count < rel->rd_att->natts; count++)
{
Form_pg_attribute inhattr = TupleDescAttr(rel->rd_att,
count);
char *inhname = NameStr(inhattr->attname);
if (inhattr->attisdropped)
continue;
if (strcmp(key, inhname) == 0)
{
found = true;
/*
* It's tempting to set forced_not_null if the
* parent column is already NOT NULL, but that
* seems unsafe because the column's NOT NULL
* marking might disappear between now and
* execution. Do the runtime check to be safe.
*/
break;
}
}
table_close(rel, NoLock);
if (found)
break;
}
}
/*
* In the ALTER TABLE case, don't complain about index keys not
* created in the command; they may well exist already.
Avoid order-of-execution problems with ALTER TABLE ADD PRIMARY KEY. Up to now, DefineIndex() was responsible for adding attnotnull constraints to the columns of a primary key, in any case where it hadn't been convenient for transformIndexConstraint() to mark those columns as is_not_null. It (or rather its minion index_check_primary_key) did this by executing an ALTER TABLE SET NOT NULL command for the target table. The trouble with this solution is that if we're creating the index due to ALTER TABLE ADD PRIMARY KEY, and the outer ALTER TABLE has additional sub-commands, the inner ALTER TABLE's operations executed at the wrong time with respect to the outer ALTER TABLE's operations. In particular, the inner ALTER would perform a validation scan at a point where the table's storage might be inconsistent with its catalog entries. (This is on the hairy edge of being a security problem, but AFAICS it isn't one because the inner scan would only be interested in the tuples' null bitmaps.) This can result in unexpected failures, such as the one seen in bug #15580 from Allison Kaptur. To fix, let's remove the attempt to do SET NOT NULL from DefineIndex(), reducing index_check_primary_key's role to verifying that the columns are already not null. (It shouldn't ever see such a case, but it seems wise to keep the check for safety.) Instead, make transformIndexConstraint() generate ALTER TABLE SET NOT NULL subcommands to be executed ahead of the ADD PRIMARY KEY operation in every case where it can't force the column to be created already-not-null. This requires only minor surgery in parse_utilcmd.c, and it makes for a much more satisfying spec for transformIndexConstraint(): it's no longer having to take it on faith that someone else will handle addition of NOT NULL constraints. To make that work, we have to move the execution of AT_SetNotNull into an ALTER pass that executes ahead of AT_PASS_ADD_INDEX. I moved it to AT_PASS_COL_ATTRS, and put that after AT_PASS_ADD_COL to avoid failure when the column is being added in the same command. This incidentally fixes a bug in the only previous usage of AT_PASS_COL_ATTRS, for AT_SetIdentity: it didn't work either for a newly-added column. Playing around with this exposed a separate bug in ALTER TABLE ONLY ... ADD PRIMARY KEY for partitioned tables. The intent of the ONLY modifier in that context is to prevent doing anything that would require holding lock for a long time --- but the implied SET NOT NULL would recurse to the child partitions, and do an expensive validation scan for any child where the column(s) were not already NOT NULL. To fix that, invent a new ALTER subcommand AT_CheckNotNull that just insists that a child column be already NOT NULL, and apply that, not AT_SetNotNull, when recursing to children in this scenario. This results in a slightly laxer definition of ALTER TABLE ONLY ... SET NOT NULL for partitioned tables, too: that command will now work as long as all children are already NOT NULL, whereas before it just threw up its hands if there were any partitions. In passing, clean up the API of generateClonedIndexStmt(): remove a useless argument, ensure that the output argument is not left undefined, update the header comment. A small side effect of this change is that no-such-column errors in ALTER TABLE ADD PRIMARY KEY now produce a different message that includes the table name, because they are now detected by the SET NOT NULL step which has historically worded its error that way. That seems fine to me, so I didn't make any effort to avoid the wording change. The basic bug #15580 is of very long standing, and these other bugs aren't new in v12 either. However, this is a pretty significant change in the way ALTER TABLE ADD PRIMARY KEY works. On balance it seems best not to back-patch, at least not till we get some more confidence that this patch has no new bugs. Patch by me, but thanks to Jie Zhang for a preliminary version. Discussion: https://postgr.es/m/15580-d1a6de5a3d65da51@postgresql.org Discussion: https://postgr.es/m/1396E95157071C4EBBA51892C5368521017F2E6E63@G08CNEXMBPEKD02.g08.fujitsu.local
2019-04-23 18:25:27 +02:00
* DefineIndex will complain about them if not.
*/
if (!found && !cxt->isalter)
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_COLUMN),
errmsg("column \"%s\" named in key does not exist", key),
parser_errposition(cxt->pstate, constraint->location)));
/* Check for PRIMARY KEY(foo, foo) */
foreach(columns, index->indexParams)
{
iparam = (IndexElem *) lfirst(columns);
if (iparam->name && strcmp(key, iparam->name) == 0)
{
if (index->primary)
ereport(ERROR,
(errcode(ERRCODE_DUPLICATE_COLUMN),
errmsg("column \"%s\" appears twice in primary key constraint",
key),
parser_errposition(cxt->pstate, constraint->location)));
else
ereport(ERROR,
(errcode(ERRCODE_DUPLICATE_COLUMN),
errmsg("column \"%s\" appears twice in unique constraint",
key),
parser_errposition(cxt->pstate, constraint->location)));
}
}
/* OK, add it to the index definition */
iparam = makeNode(IndexElem);
iparam->name = pstrdup(key);
iparam->expr = NULL;
iparam->indexcolname = NULL;
iparam->collation = NIL;
iparam->opclass = NIL;
Implement operator class parameters PostgreSQL provides set of template index access methods, where opclasses have much freedom in the semantics of indexing. These index AMs are GiST, GIN, SP-GiST and BRIN. There opclasses define representation of keys, operations on them and supported search strategies. So, it's natural that opclasses may be faced some tradeoffs, which require user-side decision. This commit implements opclass parameters allowing users to set some values, which tell opclass how to index the particular dataset. This commit doesn't introduce new storage in system catalog. Instead it uses pg_attribute.attoptions, which is used for table column storage options but unused for index attributes. In order to evade changing signature of each opclass support function, we implement unified way to pass options to opclass support functions. Options are set to fn_expr as the constant bytea expression. It's possible due to the fact that opclass support functions are executed outside of expressions, so fn_expr is unused for them. This commit comes with some examples of opclass options usage. We parametrize signature length in GiST. That applies to multiple opclasses: tsvector_ops, gist__intbig_ops, gist_ltree_ops, gist__ltree_ops, gist_trgm_ops and gist_hstore_ops. Also we parametrize maximum number of integer ranges for gist__int_ops. However, the main future usage of this feature is expected to be json, where users would be able to specify which way to index particular json parts. Catversion is bumped. Discussion: https://postgr.es/m/d22c3a18-31c7-1879-fc11-4c1ce2f5e5af%40postgrespro.ru Author: Nikita Glukhov, revised by me Reviwed-by: Nikolay Shaplov, Robert Haas, Tom Lane, Tomas Vondra, Alvaro Herrera
2020-03-30 18:17:11 +02:00
iparam->opclassopts = NIL;
iparam->ordering = SORTBY_DEFAULT;
iparam->nulls_ordering = SORTBY_NULLS_DEFAULT;
index->indexParams = lappend(index->indexParams, iparam);
Avoid order-of-execution problems with ALTER TABLE ADD PRIMARY KEY. Up to now, DefineIndex() was responsible for adding attnotnull constraints to the columns of a primary key, in any case where it hadn't been convenient for transformIndexConstraint() to mark those columns as is_not_null. It (or rather its minion index_check_primary_key) did this by executing an ALTER TABLE SET NOT NULL command for the target table. The trouble with this solution is that if we're creating the index due to ALTER TABLE ADD PRIMARY KEY, and the outer ALTER TABLE has additional sub-commands, the inner ALTER TABLE's operations executed at the wrong time with respect to the outer ALTER TABLE's operations. In particular, the inner ALTER would perform a validation scan at a point where the table's storage might be inconsistent with its catalog entries. (This is on the hairy edge of being a security problem, but AFAICS it isn't one because the inner scan would only be interested in the tuples' null bitmaps.) This can result in unexpected failures, such as the one seen in bug #15580 from Allison Kaptur. To fix, let's remove the attempt to do SET NOT NULL from DefineIndex(), reducing index_check_primary_key's role to verifying that the columns are already not null. (It shouldn't ever see such a case, but it seems wise to keep the check for safety.) Instead, make transformIndexConstraint() generate ALTER TABLE SET NOT NULL subcommands to be executed ahead of the ADD PRIMARY KEY operation in every case where it can't force the column to be created already-not-null. This requires only minor surgery in parse_utilcmd.c, and it makes for a much more satisfying spec for transformIndexConstraint(): it's no longer having to take it on faith that someone else will handle addition of NOT NULL constraints. To make that work, we have to move the execution of AT_SetNotNull into an ALTER pass that executes ahead of AT_PASS_ADD_INDEX. I moved it to AT_PASS_COL_ATTRS, and put that after AT_PASS_ADD_COL to avoid failure when the column is being added in the same command. This incidentally fixes a bug in the only previous usage of AT_PASS_COL_ATTRS, for AT_SetIdentity: it didn't work either for a newly-added column. Playing around with this exposed a separate bug in ALTER TABLE ONLY ... ADD PRIMARY KEY for partitioned tables. The intent of the ONLY modifier in that context is to prevent doing anything that would require holding lock for a long time --- but the implied SET NOT NULL would recurse to the child partitions, and do an expensive validation scan for any child where the column(s) were not already NOT NULL. To fix that, invent a new ALTER subcommand AT_CheckNotNull that just insists that a child column be already NOT NULL, and apply that, not AT_SetNotNull, when recursing to children in this scenario. This results in a slightly laxer definition of ALTER TABLE ONLY ... SET NOT NULL for partitioned tables, too: that command will now work as long as all children are already NOT NULL, whereas before it just threw up its hands if there were any partitions. In passing, clean up the API of generateClonedIndexStmt(): remove a useless argument, ensure that the output argument is not left undefined, update the header comment. A small side effect of this change is that no-such-column errors in ALTER TABLE ADD PRIMARY KEY now produce a different message that includes the table name, because they are now detected by the SET NOT NULL step which has historically worded its error that way. That seems fine to me, so I didn't make any effort to avoid the wording change. The basic bug #15580 is of very long standing, and these other bugs aren't new in v12 either. However, this is a pretty significant change in the way ALTER TABLE ADD PRIMARY KEY works. On balance it seems best not to back-patch, at least not till we get some more confidence that this patch has no new bugs. Patch by me, but thanks to Jie Zhang for a preliminary version. Discussion: https://postgr.es/m/15580-d1a6de5a3d65da51@postgresql.org Discussion: https://postgr.es/m/1396E95157071C4EBBA51892C5368521017F2E6E63@G08CNEXMBPEKD02.g08.fujitsu.local
2019-04-23 18:25:27 +02:00
/*
* For a primary-key column, also create an item for ALTER TABLE
* SET NOT NULL if we couldn't ensure it via is_not_null above.
*/
if (constraint->contype == CONSTR_PRIMARY && !forced_not_null)
Avoid order-of-execution problems with ALTER TABLE ADD PRIMARY KEY. Up to now, DefineIndex() was responsible for adding attnotnull constraints to the columns of a primary key, in any case where it hadn't been convenient for transformIndexConstraint() to mark those columns as is_not_null. It (or rather its minion index_check_primary_key) did this by executing an ALTER TABLE SET NOT NULL command for the target table. The trouble with this solution is that if we're creating the index due to ALTER TABLE ADD PRIMARY KEY, and the outer ALTER TABLE has additional sub-commands, the inner ALTER TABLE's operations executed at the wrong time with respect to the outer ALTER TABLE's operations. In particular, the inner ALTER would perform a validation scan at a point where the table's storage might be inconsistent with its catalog entries. (This is on the hairy edge of being a security problem, but AFAICS it isn't one because the inner scan would only be interested in the tuples' null bitmaps.) This can result in unexpected failures, such as the one seen in bug #15580 from Allison Kaptur. To fix, let's remove the attempt to do SET NOT NULL from DefineIndex(), reducing index_check_primary_key's role to verifying that the columns are already not null. (It shouldn't ever see such a case, but it seems wise to keep the check for safety.) Instead, make transformIndexConstraint() generate ALTER TABLE SET NOT NULL subcommands to be executed ahead of the ADD PRIMARY KEY operation in every case where it can't force the column to be created already-not-null. This requires only minor surgery in parse_utilcmd.c, and it makes for a much more satisfying spec for transformIndexConstraint(): it's no longer having to take it on faith that someone else will handle addition of NOT NULL constraints. To make that work, we have to move the execution of AT_SetNotNull into an ALTER pass that executes ahead of AT_PASS_ADD_INDEX. I moved it to AT_PASS_COL_ATTRS, and put that after AT_PASS_ADD_COL to avoid failure when the column is being added in the same command. This incidentally fixes a bug in the only previous usage of AT_PASS_COL_ATTRS, for AT_SetIdentity: it didn't work either for a newly-added column. Playing around with this exposed a separate bug in ALTER TABLE ONLY ... ADD PRIMARY KEY for partitioned tables. The intent of the ONLY modifier in that context is to prevent doing anything that would require holding lock for a long time --- but the implied SET NOT NULL would recurse to the child partitions, and do an expensive validation scan for any child where the column(s) were not already NOT NULL. To fix that, invent a new ALTER subcommand AT_CheckNotNull that just insists that a child column be already NOT NULL, and apply that, not AT_SetNotNull, when recursing to children in this scenario. This results in a slightly laxer definition of ALTER TABLE ONLY ... SET NOT NULL for partitioned tables, too: that command will now work as long as all children are already NOT NULL, whereas before it just threw up its hands if there were any partitions. In passing, clean up the API of generateClonedIndexStmt(): remove a useless argument, ensure that the output argument is not left undefined, update the header comment. A small side effect of this change is that no-such-column errors in ALTER TABLE ADD PRIMARY KEY now produce a different message that includes the table name, because they are now detected by the SET NOT NULL step which has historically worded its error that way. That seems fine to me, so I didn't make any effort to avoid the wording change. The basic bug #15580 is of very long standing, and these other bugs aren't new in v12 either. However, this is a pretty significant change in the way ALTER TABLE ADD PRIMARY KEY works. On balance it seems best not to back-patch, at least not till we get some more confidence that this patch has no new bugs. Patch by me, but thanks to Jie Zhang for a preliminary version. Discussion: https://postgr.es/m/15580-d1a6de5a3d65da51@postgresql.org Discussion: https://postgr.es/m/1396E95157071C4EBBA51892C5368521017F2E6E63@G08CNEXMBPEKD02.g08.fujitsu.local
2019-04-23 18:25:27 +02:00
{
AlterTableCmd *notnullcmd = makeNode(AlterTableCmd);
notnullcmd->subtype = AT_SetNotNull;
Avoid order-of-execution problems with ALTER TABLE ADD PRIMARY KEY. Up to now, DefineIndex() was responsible for adding attnotnull constraints to the columns of a primary key, in any case where it hadn't been convenient for transformIndexConstraint() to mark those columns as is_not_null. It (or rather its minion index_check_primary_key) did this by executing an ALTER TABLE SET NOT NULL command for the target table. The trouble with this solution is that if we're creating the index due to ALTER TABLE ADD PRIMARY KEY, and the outer ALTER TABLE has additional sub-commands, the inner ALTER TABLE's operations executed at the wrong time with respect to the outer ALTER TABLE's operations. In particular, the inner ALTER would perform a validation scan at a point where the table's storage might be inconsistent with its catalog entries. (This is on the hairy edge of being a security problem, but AFAICS it isn't one because the inner scan would only be interested in the tuples' null bitmaps.) This can result in unexpected failures, such as the one seen in bug #15580 from Allison Kaptur. To fix, let's remove the attempt to do SET NOT NULL from DefineIndex(), reducing index_check_primary_key's role to verifying that the columns are already not null. (It shouldn't ever see such a case, but it seems wise to keep the check for safety.) Instead, make transformIndexConstraint() generate ALTER TABLE SET NOT NULL subcommands to be executed ahead of the ADD PRIMARY KEY operation in every case where it can't force the column to be created already-not-null. This requires only minor surgery in parse_utilcmd.c, and it makes for a much more satisfying spec for transformIndexConstraint(): it's no longer having to take it on faith that someone else will handle addition of NOT NULL constraints. To make that work, we have to move the execution of AT_SetNotNull into an ALTER pass that executes ahead of AT_PASS_ADD_INDEX. I moved it to AT_PASS_COL_ATTRS, and put that after AT_PASS_ADD_COL to avoid failure when the column is being added in the same command. This incidentally fixes a bug in the only previous usage of AT_PASS_COL_ATTRS, for AT_SetIdentity: it didn't work either for a newly-added column. Playing around with this exposed a separate bug in ALTER TABLE ONLY ... ADD PRIMARY KEY for partitioned tables. The intent of the ONLY modifier in that context is to prevent doing anything that would require holding lock for a long time --- but the implied SET NOT NULL would recurse to the child partitions, and do an expensive validation scan for any child where the column(s) were not already NOT NULL. To fix that, invent a new ALTER subcommand AT_CheckNotNull that just insists that a child column be already NOT NULL, and apply that, not AT_SetNotNull, when recursing to children in this scenario. This results in a slightly laxer definition of ALTER TABLE ONLY ... SET NOT NULL for partitioned tables, too: that command will now work as long as all children are already NOT NULL, whereas before it just threw up its hands if there were any partitions. In passing, clean up the API of generateClonedIndexStmt(): remove a useless argument, ensure that the output argument is not left undefined, update the header comment. A small side effect of this change is that no-such-column errors in ALTER TABLE ADD PRIMARY KEY now produce a different message that includes the table name, because they are now detected by the SET NOT NULL step which has historically worded its error that way. That seems fine to me, so I didn't make any effort to avoid the wording change. The basic bug #15580 is of very long standing, and these other bugs aren't new in v12 either. However, this is a pretty significant change in the way ALTER TABLE ADD PRIMARY KEY works. On balance it seems best not to back-patch, at least not till we get some more confidence that this patch has no new bugs. Patch by me, but thanks to Jie Zhang for a preliminary version. Discussion: https://postgr.es/m/15580-d1a6de5a3d65da51@postgresql.org Discussion: https://postgr.es/m/1396E95157071C4EBBA51892C5368521017F2E6E63@G08CNEXMBPEKD02.g08.fujitsu.local
2019-04-23 18:25:27 +02:00
notnullcmd->name = pstrdup(key);
notnullcmds = lappend(notnullcmds, notnullcmd);
}
}
}
Avoid order-of-execution problems with ALTER TABLE ADD PRIMARY KEY. Up to now, DefineIndex() was responsible for adding attnotnull constraints to the columns of a primary key, in any case where it hadn't been convenient for transformIndexConstraint() to mark those columns as is_not_null. It (or rather its minion index_check_primary_key) did this by executing an ALTER TABLE SET NOT NULL command for the target table. The trouble with this solution is that if we're creating the index due to ALTER TABLE ADD PRIMARY KEY, and the outer ALTER TABLE has additional sub-commands, the inner ALTER TABLE's operations executed at the wrong time with respect to the outer ALTER TABLE's operations. In particular, the inner ALTER would perform a validation scan at a point where the table's storage might be inconsistent with its catalog entries. (This is on the hairy edge of being a security problem, but AFAICS it isn't one because the inner scan would only be interested in the tuples' null bitmaps.) This can result in unexpected failures, such as the one seen in bug #15580 from Allison Kaptur. To fix, let's remove the attempt to do SET NOT NULL from DefineIndex(), reducing index_check_primary_key's role to verifying that the columns are already not null. (It shouldn't ever see such a case, but it seems wise to keep the check for safety.) Instead, make transformIndexConstraint() generate ALTER TABLE SET NOT NULL subcommands to be executed ahead of the ADD PRIMARY KEY operation in every case where it can't force the column to be created already-not-null. This requires only minor surgery in parse_utilcmd.c, and it makes for a much more satisfying spec for transformIndexConstraint(): it's no longer having to take it on faith that someone else will handle addition of NOT NULL constraints. To make that work, we have to move the execution of AT_SetNotNull into an ALTER pass that executes ahead of AT_PASS_ADD_INDEX. I moved it to AT_PASS_COL_ATTRS, and put that after AT_PASS_ADD_COL to avoid failure when the column is being added in the same command. This incidentally fixes a bug in the only previous usage of AT_PASS_COL_ATTRS, for AT_SetIdentity: it didn't work either for a newly-added column. Playing around with this exposed a separate bug in ALTER TABLE ONLY ... ADD PRIMARY KEY for partitioned tables. The intent of the ONLY modifier in that context is to prevent doing anything that would require holding lock for a long time --- but the implied SET NOT NULL would recurse to the child partitions, and do an expensive validation scan for any child where the column(s) were not already NOT NULL. To fix that, invent a new ALTER subcommand AT_CheckNotNull that just insists that a child column be already NOT NULL, and apply that, not AT_SetNotNull, when recursing to children in this scenario. This results in a slightly laxer definition of ALTER TABLE ONLY ... SET NOT NULL for partitioned tables, too: that command will now work as long as all children are already NOT NULL, whereas before it just threw up its hands if there were any partitions. In passing, clean up the API of generateClonedIndexStmt(): remove a useless argument, ensure that the output argument is not left undefined, update the header comment. A small side effect of this change is that no-such-column errors in ALTER TABLE ADD PRIMARY KEY now produce a different message that includes the table name, because they are now detected by the SET NOT NULL step which has historically worded its error that way. That seems fine to me, so I didn't make any effort to avoid the wording change. The basic bug #15580 is of very long standing, and these other bugs aren't new in v12 either. However, this is a pretty significant change in the way ALTER TABLE ADD PRIMARY KEY works. On balance it seems best not to back-patch, at least not till we get some more confidence that this patch has no new bugs. Patch by me, but thanks to Jie Zhang for a preliminary version. Discussion: https://postgr.es/m/15580-d1a6de5a3d65da51@postgresql.org Discussion: https://postgr.es/m/1396E95157071C4EBBA51892C5368521017F2E6E63@G08CNEXMBPEKD02.g08.fujitsu.local
2019-04-23 18:25:27 +02:00
/*
* Add included columns to index definition. This is much like the
* simple-column-name-list code above, except that we don't worry about
* NOT NULL marking; included columns in a primary key should not be
* forced NOT NULL. We don't complain about duplicate columns, either,
* though maybe we should?
*/
foreach(lc, constraint->including)
{
char *key = strVal(lfirst(lc));
bool found = false;
ColumnDef *column = NULL;
ListCell *columns;
IndexElem *iparam;
foreach(columns, cxt->columns)
{
column = lfirst_node(ColumnDef, columns);
if (strcmp(column->colname, key) == 0)
{
found = true;
break;
}
}
if (!found)
{
Remove WITH OIDS support, change oid catalog column visibility. Previously tables declared WITH OIDS, including a significant fraction of the catalog tables, stored the oid column not as a normal column, but as part of the tuple header. This special column was not shown by default, which was somewhat odd, as it's often (consider e.g. pg_class.oid) one of the more important parts of a row. Neither pg_dump nor COPY included the contents of the oid column by default. The fact that the oid column was not an ordinary column necessitated a significant amount of special case code to support oid columns. That already was painful for the existing, but upcoming work aiming to make table storage pluggable, would have required expanding and duplicating that "specialness" significantly. WITH OIDS has been deprecated since 2005 (commit ff02d0a05280e0). Remove it. Removing includes: - CREATE TABLE and ALTER TABLE syntax for declaring the table to be WITH OIDS has been removed (WITH (oids[ = true]) will error out) - pg_dump does not support dumping tables declared WITH OIDS and will issue a warning when dumping one (and ignore the oid column). - restoring an pg_dump archive with pg_restore will warn when restoring a table with oid contents (and ignore the oid column) - COPY will refuse to load binary dump that includes oids. - pg_upgrade will error out when encountering tables declared WITH OIDS, they have to be altered to remove the oid column first. - Functionality to access the oid of the last inserted row (like plpgsql's RESULT_OID, spi's SPI_lastoid, ...) has been removed. The syntax for declaring a table WITHOUT OIDS (or WITH (oids = false) for CREATE TABLE) is still supported. While that requires a bit of support code, it seems unnecessary to break applications / dumps that do not use oids, and are explicit about not using them. The biggest user of WITH OID columns was postgres' catalog. This commit changes all 'magic' oid columns to be columns that are normally declared and stored. To reduce unnecessary query breakage all the newly added columns are still named 'oid', even if a table's column naming scheme would indicate 'reloid' or such. This obviously requires adapting a lot code, mostly replacing oid access via HeapTupleGetOid() with access to the underlying Form_pg_*->oid column. The bootstrap process now assigns oids for all oid columns in genbki.pl that do not have an explicit value (starting at the largest oid previously used), only oids assigned later by oids will be above FirstBootstrapObjectId. As the oid column now is a normal column the special bootstrap syntax for oids has been removed. Oids are not automatically assigned during insertion anymore, all backend code explicitly assigns oids with GetNewOidWithIndex(). For the rare case that insertions into the catalog via SQL are called for the new pg_nextoid() function can be used (which only works on catalog tables). The fact that oid columns on system tables are now normal columns means that they will be included in the set of columns expanded by * (i.e. SELECT * FROM pg_class will now include the table's oid, previously it did not). It'd not technically be hard to hide oid column by default, but that'd mean confusing behavior would either have to be carried forward forever, or it'd cause breakage down the line. While it's not unlikely that further adjustments are needed, the scope/invasiveness of the patch makes it worthwhile to get merge this now. It's painful to maintain externally, too complicated to commit after the code code freeze, and a dependency of a number of other patches. Catversion bump, for obvious reasons. Author: Andres Freund, with contributions by John Naylor Discussion: https://postgr.es/m/20180930034810.ywp2c7awz7opzcfr@alap3.anarazel.de
2018-11-21 00:36:57 +01:00
if (SystemAttributeByName(key) != NULL)
{
/*
* column will be a system column in the new table, so accept
Avoid order-of-execution problems with ALTER TABLE ADD PRIMARY KEY. Up to now, DefineIndex() was responsible for adding attnotnull constraints to the columns of a primary key, in any case where it hadn't been convenient for transformIndexConstraint() to mark those columns as is_not_null. It (or rather its minion index_check_primary_key) did this by executing an ALTER TABLE SET NOT NULL command for the target table. The trouble with this solution is that if we're creating the index due to ALTER TABLE ADD PRIMARY KEY, and the outer ALTER TABLE has additional sub-commands, the inner ALTER TABLE's operations executed at the wrong time with respect to the outer ALTER TABLE's operations. In particular, the inner ALTER would perform a validation scan at a point where the table's storage might be inconsistent with its catalog entries. (This is on the hairy edge of being a security problem, but AFAICS it isn't one because the inner scan would only be interested in the tuples' null bitmaps.) This can result in unexpected failures, such as the one seen in bug #15580 from Allison Kaptur. To fix, let's remove the attempt to do SET NOT NULL from DefineIndex(), reducing index_check_primary_key's role to verifying that the columns are already not null. (It shouldn't ever see such a case, but it seems wise to keep the check for safety.) Instead, make transformIndexConstraint() generate ALTER TABLE SET NOT NULL subcommands to be executed ahead of the ADD PRIMARY KEY operation in every case where it can't force the column to be created already-not-null. This requires only minor surgery in parse_utilcmd.c, and it makes for a much more satisfying spec for transformIndexConstraint(): it's no longer having to take it on faith that someone else will handle addition of NOT NULL constraints. To make that work, we have to move the execution of AT_SetNotNull into an ALTER pass that executes ahead of AT_PASS_ADD_INDEX. I moved it to AT_PASS_COL_ATTRS, and put that after AT_PASS_ADD_COL to avoid failure when the column is being added in the same command. This incidentally fixes a bug in the only previous usage of AT_PASS_COL_ATTRS, for AT_SetIdentity: it didn't work either for a newly-added column. Playing around with this exposed a separate bug in ALTER TABLE ONLY ... ADD PRIMARY KEY for partitioned tables. The intent of the ONLY modifier in that context is to prevent doing anything that would require holding lock for a long time --- but the implied SET NOT NULL would recurse to the child partitions, and do an expensive validation scan for any child where the column(s) were not already NOT NULL. To fix that, invent a new ALTER subcommand AT_CheckNotNull that just insists that a child column be already NOT NULL, and apply that, not AT_SetNotNull, when recursing to children in this scenario. This results in a slightly laxer definition of ALTER TABLE ONLY ... SET NOT NULL for partitioned tables, too: that command will now work as long as all children are already NOT NULL, whereas before it just threw up its hands if there were any partitions. In passing, clean up the API of generateClonedIndexStmt(): remove a useless argument, ensure that the output argument is not left undefined, update the header comment. A small side effect of this change is that no-such-column errors in ALTER TABLE ADD PRIMARY KEY now produce a different message that includes the table name, because they are now detected by the SET NOT NULL step which has historically worded its error that way. That seems fine to me, so I didn't make any effort to avoid the wording change. The basic bug #15580 is of very long standing, and these other bugs aren't new in v12 either. However, this is a pretty significant change in the way ALTER TABLE ADD PRIMARY KEY works. On balance it seems best not to back-patch, at least not till we get some more confidence that this patch has no new bugs. Patch by me, but thanks to Jie Zhang for a preliminary version. Discussion: https://postgr.es/m/15580-d1a6de5a3d65da51@postgresql.org Discussion: https://postgr.es/m/1396E95157071C4EBBA51892C5368521017F2E6E63@G08CNEXMBPEKD02.g08.fujitsu.local
2019-04-23 18:25:27 +02:00
* it.
*/
found = true;
}
else if (cxt->inhRelations)
{
/* try inherited tables */
ListCell *inher;
foreach(inher, cxt->inhRelations)
{
RangeVar *inh = lfirst_node(RangeVar, inher);
Relation rel;
int count;
rel = table_openrv(inh, AccessShareLock);
/* check user requested inheritance from valid relkind */
if (rel->rd_rel->relkind != RELKIND_RELATION &&
rel->rd_rel->relkind != RELKIND_FOREIGN_TABLE &&
rel->rd_rel->relkind != RELKIND_PARTITIONED_TABLE)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("inherited relation \"%s\" is not a table or foreign table",
inh->relname)));
for (count = 0; count < rel->rd_att->natts; count++)
{
Form_pg_attribute inhattr = TupleDescAttr(rel->rd_att,
count);
char *inhname = NameStr(inhattr->attname);
if (inhattr->attisdropped)
continue;
if (strcmp(key, inhname) == 0)
{
found = true;
break;
}
}
table_close(rel, NoLock);
if (found)
break;
}
}
}
/*
* In the ALTER TABLE case, don't complain about index keys not
* created in the command; they may well exist already. DefineIndex
Avoid order-of-execution problems with ALTER TABLE ADD PRIMARY KEY. Up to now, DefineIndex() was responsible for adding attnotnull constraints to the columns of a primary key, in any case where it hadn't been convenient for transformIndexConstraint() to mark those columns as is_not_null. It (or rather its minion index_check_primary_key) did this by executing an ALTER TABLE SET NOT NULL command for the target table. The trouble with this solution is that if we're creating the index due to ALTER TABLE ADD PRIMARY KEY, and the outer ALTER TABLE has additional sub-commands, the inner ALTER TABLE's operations executed at the wrong time with respect to the outer ALTER TABLE's operations. In particular, the inner ALTER would perform a validation scan at a point where the table's storage might be inconsistent with its catalog entries. (This is on the hairy edge of being a security problem, but AFAICS it isn't one because the inner scan would only be interested in the tuples' null bitmaps.) This can result in unexpected failures, such as the one seen in bug #15580 from Allison Kaptur. To fix, let's remove the attempt to do SET NOT NULL from DefineIndex(), reducing index_check_primary_key's role to verifying that the columns are already not null. (It shouldn't ever see such a case, but it seems wise to keep the check for safety.) Instead, make transformIndexConstraint() generate ALTER TABLE SET NOT NULL subcommands to be executed ahead of the ADD PRIMARY KEY operation in every case where it can't force the column to be created already-not-null. This requires only minor surgery in parse_utilcmd.c, and it makes for a much more satisfying spec for transformIndexConstraint(): it's no longer having to take it on faith that someone else will handle addition of NOT NULL constraints. To make that work, we have to move the execution of AT_SetNotNull into an ALTER pass that executes ahead of AT_PASS_ADD_INDEX. I moved it to AT_PASS_COL_ATTRS, and put that after AT_PASS_ADD_COL to avoid failure when the column is being added in the same command. This incidentally fixes a bug in the only previous usage of AT_PASS_COL_ATTRS, for AT_SetIdentity: it didn't work either for a newly-added column. Playing around with this exposed a separate bug in ALTER TABLE ONLY ... ADD PRIMARY KEY for partitioned tables. The intent of the ONLY modifier in that context is to prevent doing anything that would require holding lock for a long time --- but the implied SET NOT NULL would recurse to the child partitions, and do an expensive validation scan for any child where the column(s) were not already NOT NULL. To fix that, invent a new ALTER subcommand AT_CheckNotNull that just insists that a child column be already NOT NULL, and apply that, not AT_SetNotNull, when recursing to children in this scenario. This results in a slightly laxer definition of ALTER TABLE ONLY ... SET NOT NULL for partitioned tables, too: that command will now work as long as all children are already NOT NULL, whereas before it just threw up its hands if there were any partitions. In passing, clean up the API of generateClonedIndexStmt(): remove a useless argument, ensure that the output argument is not left undefined, update the header comment. A small side effect of this change is that no-such-column errors in ALTER TABLE ADD PRIMARY KEY now produce a different message that includes the table name, because they are now detected by the SET NOT NULL step which has historically worded its error that way. That seems fine to me, so I didn't make any effort to avoid the wording change. The basic bug #15580 is of very long standing, and these other bugs aren't new in v12 either. However, this is a pretty significant change in the way ALTER TABLE ADD PRIMARY KEY works. On balance it seems best not to back-patch, at least not till we get some more confidence that this patch has no new bugs. Patch by me, but thanks to Jie Zhang for a preliminary version. Discussion: https://postgr.es/m/15580-d1a6de5a3d65da51@postgresql.org Discussion: https://postgr.es/m/1396E95157071C4EBBA51892C5368521017F2E6E63@G08CNEXMBPEKD02.g08.fujitsu.local
2019-04-23 18:25:27 +02:00
* will complain about them if not.
*/
if (!found && !cxt->isalter)
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_COLUMN),
errmsg("column \"%s\" named in key does not exist", key),
parser_errposition(cxt->pstate, constraint->location)));
/* OK, add it to the index definition */
iparam = makeNode(IndexElem);
iparam->name = pstrdup(key);
iparam->expr = NULL;
iparam->indexcolname = NULL;
iparam->collation = NIL;
iparam->opclass = NIL;
Implement operator class parameters PostgreSQL provides set of template index access methods, where opclasses have much freedom in the semantics of indexing. These index AMs are GiST, GIN, SP-GiST and BRIN. There opclasses define representation of keys, operations on them and supported search strategies. So, it's natural that opclasses may be faced some tradeoffs, which require user-side decision. This commit implements opclass parameters allowing users to set some values, which tell opclass how to index the particular dataset. This commit doesn't introduce new storage in system catalog. Instead it uses pg_attribute.attoptions, which is used for table column storage options but unused for index attributes. In order to evade changing signature of each opclass support function, we implement unified way to pass options to opclass support functions. Options are set to fn_expr as the constant bytea expression. It's possible due to the fact that opclass support functions are executed outside of expressions, so fn_expr is unused for them. This commit comes with some examples of opclass options usage. We parametrize signature length in GiST. That applies to multiple opclasses: tsvector_ops, gist__intbig_ops, gist_ltree_ops, gist__ltree_ops, gist_trgm_ops and gist_hstore_ops. Also we parametrize maximum number of integer ranges for gist__int_ops. However, the main future usage of this feature is expected to be json, where users would be able to specify which way to index particular json parts. Catversion is bumped. Discussion: https://postgr.es/m/d22c3a18-31c7-1879-fc11-4c1ce2f5e5af%40postgrespro.ru Author: Nikita Glukhov, revised by me Reviwed-by: Nikolay Shaplov, Robert Haas, Tom Lane, Tomas Vondra, Alvaro Herrera
2020-03-30 18:17:11 +02:00
iparam->opclassopts = NIL;
index->indexIncludingParams = lappend(index->indexIncludingParams, iparam);
}
Avoid order-of-execution problems with ALTER TABLE ADD PRIMARY KEY. Up to now, DefineIndex() was responsible for adding attnotnull constraints to the columns of a primary key, in any case where it hadn't been convenient for transformIndexConstraint() to mark those columns as is_not_null. It (or rather its minion index_check_primary_key) did this by executing an ALTER TABLE SET NOT NULL command for the target table. The trouble with this solution is that if we're creating the index due to ALTER TABLE ADD PRIMARY KEY, and the outer ALTER TABLE has additional sub-commands, the inner ALTER TABLE's operations executed at the wrong time with respect to the outer ALTER TABLE's operations. In particular, the inner ALTER would perform a validation scan at a point where the table's storage might be inconsistent with its catalog entries. (This is on the hairy edge of being a security problem, but AFAICS it isn't one because the inner scan would only be interested in the tuples' null bitmaps.) This can result in unexpected failures, such as the one seen in bug #15580 from Allison Kaptur. To fix, let's remove the attempt to do SET NOT NULL from DefineIndex(), reducing index_check_primary_key's role to verifying that the columns are already not null. (It shouldn't ever see such a case, but it seems wise to keep the check for safety.) Instead, make transformIndexConstraint() generate ALTER TABLE SET NOT NULL subcommands to be executed ahead of the ADD PRIMARY KEY operation in every case where it can't force the column to be created already-not-null. This requires only minor surgery in parse_utilcmd.c, and it makes for a much more satisfying spec for transformIndexConstraint(): it's no longer having to take it on faith that someone else will handle addition of NOT NULL constraints. To make that work, we have to move the execution of AT_SetNotNull into an ALTER pass that executes ahead of AT_PASS_ADD_INDEX. I moved it to AT_PASS_COL_ATTRS, and put that after AT_PASS_ADD_COL to avoid failure when the column is being added in the same command. This incidentally fixes a bug in the only previous usage of AT_PASS_COL_ATTRS, for AT_SetIdentity: it didn't work either for a newly-added column. Playing around with this exposed a separate bug in ALTER TABLE ONLY ... ADD PRIMARY KEY for partitioned tables. The intent of the ONLY modifier in that context is to prevent doing anything that would require holding lock for a long time --- but the implied SET NOT NULL would recurse to the child partitions, and do an expensive validation scan for any child where the column(s) were not already NOT NULL. To fix that, invent a new ALTER subcommand AT_CheckNotNull that just insists that a child column be already NOT NULL, and apply that, not AT_SetNotNull, when recursing to children in this scenario. This results in a slightly laxer definition of ALTER TABLE ONLY ... SET NOT NULL for partitioned tables, too: that command will now work as long as all children are already NOT NULL, whereas before it just threw up its hands if there were any partitions. In passing, clean up the API of generateClonedIndexStmt(): remove a useless argument, ensure that the output argument is not left undefined, update the header comment. A small side effect of this change is that no-such-column errors in ALTER TABLE ADD PRIMARY KEY now produce a different message that includes the table name, because they are now detected by the SET NOT NULL step which has historically worded its error that way. That seems fine to me, so I didn't make any effort to avoid the wording change. The basic bug #15580 is of very long standing, and these other bugs aren't new in v12 either. However, this is a pretty significant change in the way ALTER TABLE ADD PRIMARY KEY works. On balance it seems best not to back-patch, at least not till we get some more confidence that this patch has no new bugs. Patch by me, but thanks to Jie Zhang for a preliminary version. Discussion: https://postgr.es/m/15580-d1a6de5a3d65da51@postgresql.org Discussion: https://postgr.es/m/1396E95157071C4EBBA51892C5368521017F2E6E63@G08CNEXMBPEKD02.g08.fujitsu.local
2019-04-23 18:25:27 +02:00
/*
* If we found anything that requires run-time SET NOT NULL, build a full
* ALTER TABLE command for that and add it to cxt->alist.
*/
if (notnullcmds)
{
AlterTableStmt *alterstmt = makeNode(AlterTableStmt);
alterstmt->relation = copyObject(cxt->relation);
alterstmt->cmds = notnullcmds;
alterstmt->objtype = OBJECT_TABLE;
Avoid order-of-execution problems with ALTER TABLE ADD PRIMARY KEY. Up to now, DefineIndex() was responsible for adding attnotnull constraints to the columns of a primary key, in any case where it hadn't been convenient for transformIndexConstraint() to mark those columns as is_not_null. It (or rather its minion index_check_primary_key) did this by executing an ALTER TABLE SET NOT NULL command for the target table. The trouble with this solution is that if we're creating the index due to ALTER TABLE ADD PRIMARY KEY, and the outer ALTER TABLE has additional sub-commands, the inner ALTER TABLE's operations executed at the wrong time with respect to the outer ALTER TABLE's operations. In particular, the inner ALTER would perform a validation scan at a point where the table's storage might be inconsistent with its catalog entries. (This is on the hairy edge of being a security problem, but AFAICS it isn't one because the inner scan would only be interested in the tuples' null bitmaps.) This can result in unexpected failures, such as the one seen in bug #15580 from Allison Kaptur. To fix, let's remove the attempt to do SET NOT NULL from DefineIndex(), reducing index_check_primary_key's role to verifying that the columns are already not null. (It shouldn't ever see such a case, but it seems wise to keep the check for safety.) Instead, make transformIndexConstraint() generate ALTER TABLE SET NOT NULL subcommands to be executed ahead of the ADD PRIMARY KEY operation in every case where it can't force the column to be created already-not-null. This requires only minor surgery in parse_utilcmd.c, and it makes for a much more satisfying spec for transformIndexConstraint(): it's no longer having to take it on faith that someone else will handle addition of NOT NULL constraints. To make that work, we have to move the execution of AT_SetNotNull into an ALTER pass that executes ahead of AT_PASS_ADD_INDEX. I moved it to AT_PASS_COL_ATTRS, and put that after AT_PASS_ADD_COL to avoid failure when the column is being added in the same command. This incidentally fixes a bug in the only previous usage of AT_PASS_COL_ATTRS, for AT_SetIdentity: it didn't work either for a newly-added column. Playing around with this exposed a separate bug in ALTER TABLE ONLY ... ADD PRIMARY KEY for partitioned tables. The intent of the ONLY modifier in that context is to prevent doing anything that would require holding lock for a long time --- but the implied SET NOT NULL would recurse to the child partitions, and do an expensive validation scan for any child where the column(s) were not already NOT NULL. To fix that, invent a new ALTER subcommand AT_CheckNotNull that just insists that a child column be already NOT NULL, and apply that, not AT_SetNotNull, when recursing to children in this scenario. This results in a slightly laxer definition of ALTER TABLE ONLY ... SET NOT NULL for partitioned tables, too: that command will now work as long as all children are already NOT NULL, whereas before it just threw up its hands if there were any partitions. In passing, clean up the API of generateClonedIndexStmt(): remove a useless argument, ensure that the output argument is not left undefined, update the header comment. A small side effect of this change is that no-such-column errors in ALTER TABLE ADD PRIMARY KEY now produce a different message that includes the table name, because they are now detected by the SET NOT NULL step which has historically worded its error that way. That seems fine to me, so I didn't make any effort to avoid the wording change. The basic bug #15580 is of very long standing, and these other bugs aren't new in v12 either. However, this is a pretty significant change in the way ALTER TABLE ADD PRIMARY KEY works. On balance it seems best not to back-patch, at least not till we get some more confidence that this patch has no new bugs. Patch by me, but thanks to Jie Zhang for a preliminary version. Discussion: https://postgr.es/m/15580-d1a6de5a3d65da51@postgresql.org Discussion: https://postgr.es/m/1396E95157071C4EBBA51892C5368521017F2E6E63@G08CNEXMBPEKD02.g08.fujitsu.local
2019-04-23 18:25:27 +02:00
alterstmt->missing_ok = false;
cxt->alist = lappend(cxt->alist, alterstmt);
}
return index;
}
/*
* transformExtendedStatistics
* Handle extended statistic objects
*
* Right now, there's nothing to do here, so we just append the list to
* the existing "after" list.
*/
static void
transformExtendedStatistics(CreateStmtContext *cxt)
{
cxt->alist = list_concat(cxt->alist, cxt->extstats);
}
/*
* transformCheckConstraints
* handle CHECK constraints
*
* Right now, there's nothing to do here when called from ALTER TABLE,
* but the other constraint-transformation functions are called in both
* the CREATE TABLE and ALTER TABLE paths, so do the same here, and just
* don't do anything if we're not authorized to skip validation.
*/
static void
transformCheckConstraints(CreateStmtContext *cxt, bool skipValidation)
{
ListCell *ckclist;
if (cxt->ckconstraints == NIL)
return;
/*
* If creating a new table (but not a foreign table), we can safely skip
* validation of check constraints, and nonetheless mark them valid. (This
* will override any user-supplied NOT VALID flag.)
*/
if (skipValidation)
{
foreach(ckclist, cxt->ckconstraints)
{
Constraint *constraint = (Constraint *) lfirst(ckclist);
constraint->skip_validation = true;
constraint->initially_valid = true;
}
}
}
/*
* transformFKConstraints
* handle FOREIGN KEY constraints
*/
static void
transformFKConstraints(CreateStmtContext *cxt,
bool skipValidation, bool isAddConstraint)
{
ListCell *fkclist;
if (cxt->fkconstraints == NIL)
return;
/*
* If CREATE TABLE or adding a column with NULL default, we can safely
* skip validation of FK constraints, and nonetheless mark them valid.
* (This will override any user-supplied NOT VALID flag.)
*/
if (skipValidation)
{
foreach(fkclist, cxt->fkconstraints)
{
Constraint *constraint = (Constraint *) lfirst(fkclist);
constraint->skip_validation = true;
constraint->initially_valid = true;
}
}
/*
* For CREATE TABLE or ALTER TABLE ADD COLUMN, gin up an ALTER TABLE ADD
* CONSTRAINT command to execute after the basic command is complete. (If
* called from ADD CONSTRAINT, that routine will add the FK constraints to
* its own subcommand list.)
*
* Note: the ADD CONSTRAINT command must also execute after any index
* creation commands. Thus, this should run after
* transformIndexConstraints, so that the CREATE INDEX commands are
* already in cxt->alist. See also the handling of cxt->likeclauses.
*/
if (!isAddConstraint)
{
AlterTableStmt *alterstmt = makeNode(AlterTableStmt);
alterstmt->relation = cxt->relation;
alterstmt->cmds = NIL;
alterstmt->objtype = OBJECT_TABLE;
foreach(fkclist, cxt->fkconstraints)
{
Constraint *constraint = (Constraint *) lfirst(fkclist);
AlterTableCmd *altercmd = makeNode(AlterTableCmd);
Restructure ALTER TABLE execution to fix assorted bugs. We've had numerous bug reports about how (1) IF NOT EXISTS clauses in ALTER TABLE don't behave as-expected, and (2) combining certain actions into one ALTER TABLE doesn't work, though executing the same actions as separate statements does. This patch cleans up all of the cases so far reported from the field, though there are still some oddities associated with identity columns. The core problem behind all of these bugs is that we do parse analysis of ALTER TABLE subcommands too soon, before starting execution of the statement. The root of the bugs in group (1) is that parse analysis schedules derived commands (such as a CREATE SEQUENCE for a serial column) before it's known whether the IF NOT EXISTS clause should cause a subcommand to be skipped. The root of the bugs in group (2) is that earlier subcommands may change the catalog state that later subcommands need to be parsed against. Hence, postpone parse analysis of ALTER TABLE's subcommands, and do that one subcommand at a time, during "phase 2" of ALTER TABLE which is the phase that does catalog rewrites. Thus the catalog effects of earlier subcommands are already visible when we analyze later ones. (The sole exception is that we do parse analysis for ALTER COLUMN TYPE subcommands during phase 1, so that their USING expressions can be parsed against the table's original state, which is what we need. Arguably, these bugs stem from falsely concluding that because ALTER COLUMN TYPE must do early parse analysis, every other command subtype can too.) This means that ALTER TABLE itself must deal with execution of any non-ALTER-TABLE derived statements that are generated by parse analysis. Add a suitable entry point to utility.c to accept those recursive calls, and create a struct to pass through the information needed by the recursive call, rather than making the argument lists of AlterTable() and friends even longer. Getting this to work correctly required a little bit of fiddling with the subcommand pass structure, in particular breaking up AT_PASS_ADD_CONSTR into multiple passes. But otherwise it's mostly a pretty straightforward application of the above ideas. Fixing the residual issues for identity columns requires refactoring of where the dependency link from an identity column to its sequence gets set up. So that seems like suitable material for a separate patch, especially since this one is pretty big already. Discussion: https://postgr.es/m/10365.1558909428@sss.pgh.pa.us
2020-01-16 00:49:24 +01:00
altercmd->subtype = AT_AddConstraint;
altercmd->name = NULL;
altercmd->def = (Node *) constraint;
alterstmt->cmds = lappend(alterstmt->cmds, altercmd);
}
cxt->alist = lappend(cxt->alist, alterstmt);
}
}
/*
* transformIndexStmt - parse analysis for CREATE INDEX and ALTER TABLE
*
* Note: this is a no-op for an index not using either index expressions or
* a predicate expression. There are several code paths that create indexes
* without bothering to call this, because they know they don't have any
* such expressions to deal with.
*
* To avoid race conditions, it's important that this function rely only on
* the passed-in relid (and not on stmt->relation) to determine the target
* relation.
*/
IndexStmt *
transformIndexStmt(Oid relid, IndexStmt *stmt, const char *queryString)
{
ParseState *pstate;
Make parser rely more heavily on the ParseNamespaceItem data structure. When I added the ParseNamespaceItem data structure (in commit 5ebaaa494), it wasn't very tightly integrated into the parser's APIs. In the wake of adding p_rtindex to that struct (commit b541e9acc), there is a good reason to make more use of it: by passing around ParseNamespaceItem pointers instead of bare RTE pointers, we can get rid of various messy methods for passing back or deducing the rangetable index of an RTE during parsing. Hence, refactor the addRangeTableEntryXXX functions to build and return a ParseNamespaceItem struct, not just the RTE proper; and replace addRTEtoQuery with addNSItemToQuery, which is passed a ParseNamespaceItem rather than building one internally. Also, add per-column data (a ParseNamespaceColumn array) to each ParseNamespaceItem. These arrays are built during addRangeTableEntryXXX, where we have column type data at hand so that it's nearly free to fill the data structure. Later, when we need to build Vars referencing RTEs, we can use the ParseNamespaceColumn info to avoid the rather expensive operations done in get_rte_attribute_type() or expandRTE(). get_rte_attribute_type() is indeed dead code now, so I've removed it. This makes for a useful improvement in parse analysis speed, around 20% in one moderately-complex test query. The ParseNamespaceColumn structs also include Var identity information (varno/varattno). That info isn't actually being used in this patch, except that p_varno == 0 is a handy test for a dropped column. A follow-on patch will make more use of it. Discussion: https://postgr.es/m/2461.1577764221@sss.pgh.pa.us
2020-01-02 17:29:01 +01:00
ParseNamespaceItem *nsitem;
ListCell *l;
Relation rel;
Get rid of multiple applications of transformExpr() to the same tree. transformExpr() has for many years had provisions to do nothing when applied to an already-transformed expression tree. However, this was always ugly and of dubious reliability, so we'd be much better off without it. The primary historical reason for it was that gram.y sometimes returned multiple links to the same subexpression, which is no longer true as of my BETWEEN fixes. We'd also grown some lazy hacks in CREATE TABLE LIKE (failing to distinguish between raw and already-transformed index specifications) and one or two other places. This patch removes the need for and support for re-transforming already transformed expressions. The index case is dealt with by adding a flag to struct IndexStmt to indicate that it's already been transformed; which has some benefit anyway in that tablecmds.c can now Assert that transformation has happened rather than just assuming. The other main reason was some rather sloppy code for array type coercion, which can be fixed (and its performance improved too) by refactoring. I did leave transformJoinUsingClause() still constructing expressions containing untransformed operator nodes being applied to Vars, so that transformExpr() still has to allow Var inputs. But that's a much narrower, and safer, special case than before, since Vars will never appear in a raw parse tree, and they don't have any substructure to worry about. In passing fix some oversights in the patch that added CREATE INDEX IF NOT EXISTS (missing processing of IndexStmt.if_not_exists). These appear relatively harmless, but still sloppy coding practice.
2015-02-22 19:59:09 +01:00
/* Nothing to do if statement already transformed. */
if (stmt->transformed)
return stmt;
/* Set up pstate */
pstate = make_parsestate(NULL);
pstate->p_sourcetext = queryString;
/*
* Put the parent table into the rtable so that the expressions can refer
* to its fields without qualification. Caller is responsible for locking
* relation, but we still need to open it.
*/
rel = relation_open(relid, NoLock);
Make parser rely more heavily on the ParseNamespaceItem data structure. When I added the ParseNamespaceItem data structure (in commit 5ebaaa494), it wasn't very tightly integrated into the parser's APIs. In the wake of adding p_rtindex to that struct (commit b541e9acc), there is a good reason to make more use of it: by passing around ParseNamespaceItem pointers instead of bare RTE pointers, we can get rid of various messy methods for passing back or deducing the rangetable index of an RTE during parsing. Hence, refactor the addRangeTableEntryXXX functions to build and return a ParseNamespaceItem struct, not just the RTE proper; and replace addRTEtoQuery with addNSItemToQuery, which is passed a ParseNamespaceItem rather than building one internally. Also, add per-column data (a ParseNamespaceColumn array) to each ParseNamespaceItem. These arrays are built during addRangeTableEntryXXX, where we have column type data at hand so that it's nearly free to fill the data structure. Later, when we need to build Vars referencing RTEs, we can use the ParseNamespaceColumn info to avoid the rather expensive operations done in get_rte_attribute_type() or expandRTE(). get_rte_attribute_type() is indeed dead code now, so I've removed it. This makes for a useful improvement in parse analysis speed, around 20% in one moderately-complex test query. The ParseNamespaceColumn structs also include Var identity information (varno/varattno). That info isn't actually being used in this patch, except that p_varno == 0 is a handy test for a dropped column. A follow-on patch will make more use of it. Discussion: https://postgr.es/m/2461.1577764221@sss.pgh.pa.us
2020-01-02 17:29:01 +01:00
nsitem = addRangeTableEntryForRelation(pstate, rel,
AccessShareLock,
NULL, false, true);
/* no to join list, yes to namespaces */
Make parser rely more heavily on the ParseNamespaceItem data structure. When I added the ParseNamespaceItem data structure (in commit 5ebaaa494), it wasn't very tightly integrated into the parser's APIs. In the wake of adding p_rtindex to that struct (commit b541e9acc), there is a good reason to make more use of it: by passing around ParseNamespaceItem pointers instead of bare RTE pointers, we can get rid of various messy methods for passing back or deducing the rangetable index of an RTE during parsing. Hence, refactor the addRangeTableEntryXXX functions to build and return a ParseNamespaceItem struct, not just the RTE proper; and replace addRTEtoQuery with addNSItemToQuery, which is passed a ParseNamespaceItem rather than building one internally. Also, add per-column data (a ParseNamespaceColumn array) to each ParseNamespaceItem. These arrays are built during addRangeTableEntryXXX, where we have column type data at hand so that it's nearly free to fill the data structure. Later, when we need to build Vars referencing RTEs, we can use the ParseNamespaceColumn info to avoid the rather expensive operations done in get_rte_attribute_type() or expandRTE(). get_rte_attribute_type() is indeed dead code now, so I've removed it. This makes for a useful improvement in parse analysis speed, around 20% in one moderately-complex test query. The ParseNamespaceColumn structs also include Var identity information (varno/varattno). That info isn't actually being used in this patch, except that p_varno == 0 is a handy test for a dropped column. A follow-on patch will make more use of it. Discussion: https://postgr.es/m/2461.1577764221@sss.pgh.pa.us
2020-01-02 17:29:01 +01:00
addNSItemToQuery(pstate, nsitem, false, true, true);
/* take care of the where clause */
if (stmt->whereClause)
{
stmt->whereClause = transformWhereClause(pstate,
stmt->whereClause,
EXPR_KIND_INDEX_PREDICATE,
"WHERE");
/* we have to fix its collations too */
assign_expr_collations(pstate, stmt->whereClause);
}
/* take care of any index expressions */
foreach(l, stmt->indexParams)
{
IndexElem *ielem = (IndexElem *) lfirst(l);
if (ielem->expr)
{
/* Extract preliminary index col name before transforming expr */
if (ielem->indexcolname == NULL)
ielem->indexcolname = FigureIndexColname(ielem->expr);
/* Now do parse transformation of the expression */
ielem->expr = transformExpr(pstate, ielem->expr,
EXPR_KIND_INDEX_EXPRESSION);
/* We have to fix its collations too */
assign_expr_collations(pstate, ielem->expr);
/*
* transformExpr() should have already rejected subqueries,
Improve parser's and planner's handling of set-returning functions. Teach the parser to reject misplaced set-returning functions during parse analysis using p_expr_kind, in much the same way as we do for aggregates and window functions (cf commit eaccfded9). While this isn't complete (it misses nesting-based restrictions), it's much better than the previous error reporting for such cases, and it allows elimination of assorted ad-hoc expression_returns_set() error checks. We could add nesting checks later if it seems important to catch all cases at parse time. There is one case the parser will now throw error for although previous versions allowed it, which is SRFs in the tlist of an UPDATE. That never behaved sensibly (since it's ill-defined which generated row should be used to perform the update) and it's hard to see why it should not be treated as an error. It's a release-note-worthy change though. Also, add a new Query field hasTargetSRFs reporting whether there are any SRFs in the targetlist (including GROUP BY/ORDER BY expressions). The parser can now set that basically for free during parse analysis, and we can use it in a number of places to avoid expression_returns_set searches. (There will be more such checks soon.) In some places, this allows decontorting the logic since it's no longer expensive to check for SRFs in the tlist --- so I made the checks parallel to the handling of hasAggs/hasWindowFuncs wherever it seemed appropriate. catversion bump because adding a Query field changes stored rules. Andres Freund and Tom Lane Discussion: <24639.1473782855@sss.pgh.pa.us>
2016-09-13 19:54:24 +02:00
* aggregates, window functions, and SRFs, based on the EXPR_KIND_
* for an index expression.
*
* DefineIndex() will make more checks.
*/
}
}
/*
* Check that only the base rel is mentioned. (This should be dead code
* now that add_missing_from is history.)
*/
if (list_length(pstate->p_rtable) != 1)
ereport(ERROR,
(errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
errmsg("index expressions and predicates can refer only to the table being indexed")));
free_parsestate(pstate);
/* Close relation */
table_close(rel, NoLock);
Get rid of multiple applications of transformExpr() to the same tree. transformExpr() has for many years had provisions to do nothing when applied to an already-transformed expression tree. However, this was always ugly and of dubious reliability, so we'd be much better off without it. The primary historical reason for it was that gram.y sometimes returned multiple links to the same subexpression, which is no longer true as of my BETWEEN fixes. We'd also grown some lazy hacks in CREATE TABLE LIKE (failing to distinguish between raw and already-transformed index specifications) and one or two other places. This patch removes the need for and support for re-transforming already transformed expressions. The index case is dealt with by adding a flag to struct IndexStmt to indicate that it's already been transformed; which has some benefit anyway in that tablecmds.c can now Assert that transformation has happened rather than just assuming. The other main reason was some rather sloppy code for array type coercion, which can be fixed (and its performance improved too) by refactoring. I did leave transformJoinUsingClause() still constructing expressions containing untransformed operator nodes being applied to Vars, so that transformExpr() still has to allow Var inputs. But that's a much narrower, and safer, special case than before, since Vars will never appear in a raw parse tree, and they don't have any substructure to worry about. In passing fix some oversights in the patch that added CREATE INDEX IF NOT EXISTS (missing processing of IndexStmt.if_not_exists). These appear relatively harmless, but still sloppy coding practice.
2015-02-22 19:59:09 +01:00
/* Mark statement as successfully transformed */
stmt->transformed = true;
return stmt;
}
Extended statistics on expressions Allow defining extended statistics on expressions, not just just on simple column references. With this commit, expressions are supported by all existing extended statistics kinds, improving the same types of estimates. A simple example may look like this: CREATE TABLE t (a int); CREATE STATISTICS s ON mod(a,10), mod(a,20) FROM t; ANALYZE t; The collected statistics are useful e.g. to estimate queries with those expressions in WHERE or GROUP BY clauses: SELECT * FROM t WHERE mod(a,10) = 0 AND mod(a,20) = 0; SELECT 1 FROM t GROUP BY mod(a,10), mod(a,20); This introduces new internal statistics kind 'e' (expressions) which is built automatically when the statistics object definition includes any expressions. This represents single-expression statistics, as if there was an expression index (but without the index maintenance overhead). The statistics is stored in pg_statistics_ext_data as an array of composite types, which is possible thanks to 79f6a942bd. CREATE STATISTICS allows building statistics on a single expression, in which case in which case it's not possible to specify statistics kinds. A new system view pg_stats_ext_exprs can be used to display expression statistics, similarly to pg_stats and pg_stats_ext views. ALTER TABLE ... ALTER COLUMN ... TYPE now treats indexes the same way it treats indexes, i.e. it drops and recreates the statistics. This means all statistics are reset, and we no longer try to preserve at least the functional dependencies. This should not be a major issue in practice, as the functional dependencies actually rely on per-column statistics, which were always reset anyway. Author: Tomas Vondra Reviewed-by: Justin Pryzby, Dean Rasheed, Zhihong Yu Discussion: https://postgr.es/m/ad7891d2-e90c-b446-9fe2-7419143847d7%40enterprisedb.com
2021-03-26 23:22:01 +01:00
/*
* transformStatsStmt - parse analysis for CREATE STATISTICS
*
* To avoid race conditions, it's important that this function relies only on
Extended statistics on expressions Allow defining extended statistics on expressions, not just just on simple column references. With this commit, expressions are supported by all existing extended statistics kinds, improving the same types of estimates. A simple example may look like this: CREATE TABLE t (a int); CREATE STATISTICS s ON mod(a,10), mod(a,20) FROM t; ANALYZE t; The collected statistics are useful e.g. to estimate queries with those expressions in WHERE or GROUP BY clauses: SELECT * FROM t WHERE mod(a,10) = 0 AND mod(a,20) = 0; SELECT 1 FROM t GROUP BY mod(a,10), mod(a,20); This introduces new internal statistics kind 'e' (expressions) which is built automatically when the statistics object definition includes any expressions. This represents single-expression statistics, as if there was an expression index (but without the index maintenance overhead). The statistics is stored in pg_statistics_ext_data as an array of composite types, which is possible thanks to 79f6a942bd. CREATE STATISTICS allows building statistics on a single expression, in which case in which case it's not possible to specify statistics kinds. A new system view pg_stats_ext_exprs can be used to display expression statistics, similarly to pg_stats and pg_stats_ext views. ALTER TABLE ... ALTER COLUMN ... TYPE now treats indexes the same way it treats indexes, i.e. it drops and recreates the statistics. This means all statistics are reset, and we no longer try to preserve at least the functional dependencies. This should not be a major issue in practice, as the functional dependencies actually rely on per-column statistics, which were always reset anyway. Author: Tomas Vondra Reviewed-by: Justin Pryzby, Dean Rasheed, Zhihong Yu Discussion: https://postgr.es/m/ad7891d2-e90c-b446-9fe2-7419143847d7%40enterprisedb.com
2021-03-26 23:22:01 +01:00
* the passed-in relid (and not on stmt->relation) to determine the target
* relation.
*/
CreateStatsStmt *
transformStatsStmt(Oid relid, CreateStatsStmt *stmt, const char *queryString)
{
ParseState *pstate;
ParseNamespaceItem *nsitem;
ListCell *l;
Relation rel;
/* Nothing to do if statement already transformed. */
if (stmt->transformed)
return stmt;
/* Set up pstate */
pstate = make_parsestate(NULL);
pstate->p_sourcetext = queryString;
/*
* Put the parent table into the rtable so that the expressions can refer
* to its fields without qualification. Caller is responsible for locking
* relation, but we still need to open it.
*/
rel = relation_open(relid, NoLock);
nsitem = addRangeTableEntryForRelation(pstate, rel,
AccessShareLock,
NULL, false, true);
/* no to join list, yes to namespaces */
addNSItemToQuery(pstate, nsitem, false, true, true);
/* take care of any expressions */
foreach(l, stmt->exprs)
{
StatsElem *selem = (StatsElem *) lfirst(l);
if (selem->expr)
{
/* Now do parse transformation of the expression */
selem->expr = transformExpr(pstate, selem->expr,
EXPR_KIND_STATS_EXPRESSION);
/* We have to fix its collations too */
assign_expr_collations(pstate, selem->expr);
}
}
/*
* Check that only the base rel is mentioned. (This should be dead code
* now that add_missing_from is history.)
*/
if (list_length(pstate->p_rtable) != 1)
ereport(ERROR,
(errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
errmsg("statistics expressions can refer only to the table being referenced")));
Extended statistics on expressions Allow defining extended statistics on expressions, not just just on simple column references. With this commit, expressions are supported by all existing extended statistics kinds, improving the same types of estimates. A simple example may look like this: CREATE TABLE t (a int); CREATE STATISTICS s ON mod(a,10), mod(a,20) FROM t; ANALYZE t; The collected statistics are useful e.g. to estimate queries with those expressions in WHERE or GROUP BY clauses: SELECT * FROM t WHERE mod(a,10) = 0 AND mod(a,20) = 0; SELECT 1 FROM t GROUP BY mod(a,10), mod(a,20); This introduces new internal statistics kind 'e' (expressions) which is built automatically when the statistics object definition includes any expressions. This represents single-expression statistics, as if there was an expression index (but without the index maintenance overhead). The statistics is stored in pg_statistics_ext_data as an array of composite types, which is possible thanks to 79f6a942bd. CREATE STATISTICS allows building statistics on a single expression, in which case in which case it's not possible to specify statistics kinds. A new system view pg_stats_ext_exprs can be used to display expression statistics, similarly to pg_stats and pg_stats_ext views. ALTER TABLE ... ALTER COLUMN ... TYPE now treats indexes the same way it treats indexes, i.e. it drops and recreates the statistics. This means all statistics are reset, and we no longer try to preserve at least the functional dependencies. This should not be a major issue in practice, as the functional dependencies actually rely on per-column statistics, which were always reset anyway. Author: Tomas Vondra Reviewed-by: Justin Pryzby, Dean Rasheed, Zhihong Yu Discussion: https://postgr.es/m/ad7891d2-e90c-b446-9fe2-7419143847d7%40enterprisedb.com
2021-03-26 23:22:01 +01:00
free_parsestate(pstate);
/* Close relation */
table_close(rel, NoLock);
/* Mark statement as successfully transformed */
stmt->transformed = true;
return stmt;
}
/*
* transformRuleStmt -
* transform a CREATE RULE Statement. The action is a list of parse
* trees which is transformed into a list of query trees, and we also
* transform the WHERE clause if any.
*
* actions and whereClause are output parameters that receive the
* transformed results.
*/
void
transformRuleStmt(RuleStmt *stmt, const char *queryString,
List **actions, Node **whereClause)
{
Relation rel;
ParseState *pstate;
Make parser rely more heavily on the ParseNamespaceItem data structure. When I added the ParseNamespaceItem data structure (in commit 5ebaaa494), it wasn't very tightly integrated into the parser's APIs. In the wake of adding p_rtindex to that struct (commit b541e9acc), there is a good reason to make more use of it: by passing around ParseNamespaceItem pointers instead of bare RTE pointers, we can get rid of various messy methods for passing back or deducing the rangetable index of an RTE during parsing. Hence, refactor the addRangeTableEntryXXX functions to build and return a ParseNamespaceItem struct, not just the RTE proper; and replace addRTEtoQuery with addNSItemToQuery, which is passed a ParseNamespaceItem rather than building one internally. Also, add per-column data (a ParseNamespaceColumn array) to each ParseNamespaceItem. These arrays are built during addRangeTableEntryXXX, where we have column type data at hand so that it's nearly free to fill the data structure. Later, when we need to build Vars referencing RTEs, we can use the ParseNamespaceColumn info to avoid the rather expensive operations done in get_rte_attribute_type() or expandRTE(). get_rte_attribute_type() is indeed dead code now, so I've removed it. This makes for a useful improvement in parse analysis speed, around 20% in one moderately-complex test query. The ParseNamespaceColumn structs also include Var identity information (varno/varattno). That info isn't actually being used in this patch, except that p_varno == 0 is a handy test for a dropped column. A follow-on patch will make more use of it. Discussion: https://postgr.es/m/2461.1577764221@sss.pgh.pa.us
2020-01-02 17:29:01 +01:00
ParseNamespaceItem *oldnsitem;
ParseNamespaceItem *newnsitem;
/*
* To avoid deadlock, make sure the first thing we do is grab
* AccessExclusiveLock on the target relation. This will be needed by
* DefineQueryRewrite(), and we don't want to grab a lesser lock
* beforehand.
*/
rel = table_openrv(stmt->relation, AccessExclusiveLock);
if (rel->rd_rel->relkind == RELKIND_MATVIEW)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("rules on materialized views are not supported")));
/* Set up pstate */
pstate = make_parsestate(NULL);
pstate->p_sourcetext = queryString;
/*
* NOTE: 'OLD' must always have a varno equal to 1 and 'NEW' equal to 2.
Make parser rely more heavily on the ParseNamespaceItem data structure. When I added the ParseNamespaceItem data structure (in commit 5ebaaa494), it wasn't very tightly integrated into the parser's APIs. In the wake of adding p_rtindex to that struct (commit b541e9acc), there is a good reason to make more use of it: by passing around ParseNamespaceItem pointers instead of bare RTE pointers, we can get rid of various messy methods for passing back or deducing the rangetable index of an RTE during parsing. Hence, refactor the addRangeTableEntryXXX functions to build and return a ParseNamespaceItem struct, not just the RTE proper; and replace addRTEtoQuery with addNSItemToQuery, which is passed a ParseNamespaceItem rather than building one internally. Also, add per-column data (a ParseNamespaceColumn array) to each ParseNamespaceItem. These arrays are built during addRangeTableEntryXXX, where we have column type data at hand so that it's nearly free to fill the data structure. Later, when we need to build Vars referencing RTEs, we can use the ParseNamespaceColumn info to avoid the rather expensive operations done in get_rte_attribute_type() or expandRTE(). get_rte_attribute_type() is indeed dead code now, so I've removed it. This makes for a useful improvement in parse analysis speed, around 20% in one moderately-complex test query. The ParseNamespaceColumn structs also include Var identity information (varno/varattno). That info isn't actually being used in this patch, except that p_varno == 0 is a handy test for a dropped column. A follow-on patch will make more use of it. Discussion: https://postgr.es/m/2461.1577764221@sss.pgh.pa.us
2020-01-02 17:29:01 +01:00
* Set up their ParseNamespaceItems in the main pstate for use in parsing
* the rule qualification.
*/
Make parser rely more heavily on the ParseNamespaceItem data structure. When I added the ParseNamespaceItem data structure (in commit 5ebaaa494), it wasn't very tightly integrated into the parser's APIs. In the wake of adding p_rtindex to that struct (commit b541e9acc), there is a good reason to make more use of it: by passing around ParseNamespaceItem pointers instead of bare RTE pointers, we can get rid of various messy methods for passing back or deducing the rangetable index of an RTE during parsing. Hence, refactor the addRangeTableEntryXXX functions to build and return a ParseNamespaceItem struct, not just the RTE proper; and replace addRTEtoQuery with addNSItemToQuery, which is passed a ParseNamespaceItem rather than building one internally. Also, add per-column data (a ParseNamespaceColumn array) to each ParseNamespaceItem. These arrays are built during addRangeTableEntryXXX, where we have column type data at hand so that it's nearly free to fill the data structure. Later, when we need to build Vars referencing RTEs, we can use the ParseNamespaceColumn info to avoid the rather expensive operations done in get_rte_attribute_type() or expandRTE(). get_rte_attribute_type() is indeed dead code now, so I've removed it. This makes for a useful improvement in parse analysis speed, around 20% in one moderately-complex test query. The ParseNamespaceColumn structs also include Var identity information (varno/varattno). That info isn't actually being used in this patch, except that p_varno == 0 is a handy test for a dropped column. A follow-on patch will make more use of it. Discussion: https://postgr.es/m/2461.1577764221@sss.pgh.pa.us
2020-01-02 17:29:01 +01:00
oldnsitem = addRangeTableEntryForRelation(pstate, rel,
AccessShareLock,
makeAlias("old", NIL),
false, false);
newnsitem = addRangeTableEntryForRelation(pstate, rel,
AccessShareLock,
makeAlias("new", NIL),
false, false);
/*
* They must be in the namespace too for lookup purposes, but only add the
* one(s) that are relevant for the current kind of rule. In an UPDATE
* rule, quals must refer to OLD.field or NEW.field to be unambiguous, but
* there's no need to be so picky for INSERT & DELETE. We do not add them
* to the joinlist.
*/
switch (stmt->event)
{
case CMD_SELECT:
Make parser rely more heavily on the ParseNamespaceItem data structure. When I added the ParseNamespaceItem data structure (in commit 5ebaaa494), it wasn't very tightly integrated into the parser's APIs. In the wake of adding p_rtindex to that struct (commit b541e9acc), there is a good reason to make more use of it: by passing around ParseNamespaceItem pointers instead of bare RTE pointers, we can get rid of various messy methods for passing back or deducing the rangetable index of an RTE during parsing. Hence, refactor the addRangeTableEntryXXX functions to build and return a ParseNamespaceItem struct, not just the RTE proper; and replace addRTEtoQuery with addNSItemToQuery, which is passed a ParseNamespaceItem rather than building one internally. Also, add per-column data (a ParseNamespaceColumn array) to each ParseNamespaceItem. These arrays are built during addRangeTableEntryXXX, where we have column type data at hand so that it's nearly free to fill the data structure. Later, when we need to build Vars referencing RTEs, we can use the ParseNamespaceColumn info to avoid the rather expensive operations done in get_rte_attribute_type() or expandRTE(). get_rte_attribute_type() is indeed dead code now, so I've removed it. This makes for a useful improvement in parse analysis speed, around 20% in one moderately-complex test query. The ParseNamespaceColumn structs also include Var identity information (varno/varattno). That info isn't actually being used in this patch, except that p_varno == 0 is a handy test for a dropped column. A follow-on patch will make more use of it. Discussion: https://postgr.es/m/2461.1577764221@sss.pgh.pa.us
2020-01-02 17:29:01 +01:00
addNSItemToQuery(pstate, oldnsitem, false, true, true);
break;
case CMD_UPDATE:
Make parser rely more heavily on the ParseNamespaceItem data structure. When I added the ParseNamespaceItem data structure (in commit 5ebaaa494), it wasn't very tightly integrated into the parser's APIs. In the wake of adding p_rtindex to that struct (commit b541e9acc), there is a good reason to make more use of it: by passing around ParseNamespaceItem pointers instead of bare RTE pointers, we can get rid of various messy methods for passing back or deducing the rangetable index of an RTE during parsing. Hence, refactor the addRangeTableEntryXXX functions to build and return a ParseNamespaceItem struct, not just the RTE proper; and replace addRTEtoQuery with addNSItemToQuery, which is passed a ParseNamespaceItem rather than building one internally. Also, add per-column data (a ParseNamespaceColumn array) to each ParseNamespaceItem. These arrays are built during addRangeTableEntryXXX, where we have column type data at hand so that it's nearly free to fill the data structure. Later, when we need to build Vars referencing RTEs, we can use the ParseNamespaceColumn info to avoid the rather expensive operations done in get_rte_attribute_type() or expandRTE(). get_rte_attribute_type() is indeed dead code now, so I've removed it. This makes for a useful improvement in parse analysis speed, around 20% in one moderately-complex test query. The ParseNamespaceColumn structs also include Var identity information (varno/varattno). That info isn't actually being used in this patch, except that p_varno == 0 is a handy test for a dropped column. A follow-on patch will make more use of it. Discussion: https://postgr.es/m/2461.1577764221@sss.pgh.pa.us
2020-01-02 17:29:01 +01:00
addNSItemToQuery(pstate, oldnsitem, false, true, true);
addNSItemToQuery(pstate, newnsitem, false, true, true);
break;
case CMD_INSERT:
Make parser rely more heavily on the ParseNamespaceItem data structure. When I added the ParseNamespaceItem data structure (in commit 5ebaaa494), it wasn't very tightly integrated into the parser's APIs. In the wake of adding p_rtindex to that struct (commit b541e9acc), there is a good reason to make more use of it: by passing around ParseNamespaceItem pointers instead of bare RTE pointers, we can get rid of various messy methods for passing back or deducing the rangetable index of an RTE during parsing. Hence, refactor the addRangeTableEntryXXX functions to build and return a ParseNamespaceItem struct, not just the RTE proper; and replace addRTEtoQuery with addNSItemToQuery, which is passed a ParseNamespaceItem rather than building one internally. Also, add per-column data (a ParseNamespaceColumn array) to each ParseNamespaceItem. These arrays are built during addRangeTableEntryXXX, where we have column type data at hand so that it's nearly free to fill the data structure. Later, when we need to build Vars referencing RTEs, we can use the ParseNamespaceColumn info to avoid the rather expensive operations done in get_rte_attribute_type() or expandRTE(). get_rte_attribute_type() is indeed dead code now, so I've removed it. This makes for a useful improvement in parse analysis speed, around 20% in one moderately-complex test query. The ParseNamespaceColumn structs also include Var identity information (varno/varattno). That info isn't actually being used in this patch, except that p_varno == 0 is a handy test for a dropped column. A follow-on patch will make more use of it. Discussion: https://postgr.es/m/2461.1577764221@sss.pgh.pa.us
2020-01-02 17:29:01 +01:00
addNSItemToQuery(pstate, newnsitem, false, true, true);
break;
case CMD_DELETE:
Make parser rely more heavily on the ParseNamespaceItem data structure. When I added the ParseNamespaceItem data structure (in commit 5ebaaa494), it wasn't very tightly integrated into the parser's APIs. In the wake of adding p_rtindex to that struct (commit b541e9acc), there is a good reason to make more use of it: by passing around ParseNamespaceItem pointers instead of bare RTE pointers, we can get rid of various messy methods for passing back or deducing the rangetable index of an RTE during parsing. Hence, refactor the addRangeTableEntryXXX functions to build and return a ParseNamespaceItem struct, not just the RTE proper; and replace addRTEtoQuery with addNSItemToQuery, which is passed a ParseNamespaceItem rather than building one internally. Also, add per-column data (a ParseNamespaceColumn array) to each ParseNamespaceItem. These arrays are built during addRangeTableEntryXXX, where we have column type data at hand so that it's nearly free to fill the data structure. Later, when we need to build Vars referencing RTEs, we can use the ParseNamespaceColumn info to avoid the rather expensive operations done in get_rte_attribute_type() or expandRTE(). get_rte_attribute_type() is indeed dead code now, so I've removed it. This makes for a useful improvement in parse analysis speed, around 20% in one moderately-complex test query. The ParseNamespaceColumn structs also include Var identity information (varno/varattno). That info isn't actually being used in this patch, except that p_varno == 0 is a handy test for a dropped column. A follow-on patch will make more use of it. Discussion: https://postgr.es/m/2461.1577764221@sss.pgh.pa.us
2020-01-02 17:29:01 +01:00
addNSItemToQuery(pstate, oldnsitem, false, true, true);
break;
default:
elog(ERROR, "unrecognized event type: %d",
(int) stmt->event);
break;
}
/* take care of the where clause */
*whereClause = transformWhereClause(pstate,
Centralize the logic for protective copying of utility statements. In the "simple Query" code path, it's fine for parse analysis or execution of a utility statement to scribble on the statement's node tree, since that'll just be thrown away afterwards. However it's not fine if the node tree is in the plan cache, as then it'd be corrupted for subsequent executions. Up to now we've dealt with that by having individual utility-statement functions apply copyObject() if they were going to modify the tree. But that's prone to errors of omission. Bug #17053 from Charles Samborski shows that CREATE/ALTER DOMAIN didn't get this memo, and can crash if executed repeatedly from plan cache. In the back branches, we'll just apply a narrow band-aid for that, but in HEAD it seems prudent to have a more principled fix that will close off the possibility of other similar bugs in future. Hence, let's hoist the responsibility for doing copyObject up into ProcessUtility from its children, thus ensuring that it happens for all utility statement types. Also, modify ProcessUtility's API so that its callers can tell it whether a copy step is necessary. It turns out that in all cases, the immediate caller knows whether the node tree is transient, so this doesn't involve a huge amount of code thrashing. In this way, while we lose a little bit in the execute-from-cache code path due to sometimes copying node trees that wouldn't be mutated anyway, we gain something in the simple-Query code path by not copying throwaway node trees. Statements that are complex enough to be expensive to copy are almost certainly ones that would have to be copied anyway, so the loss in the cache code path shouldn't be much. (Note that this whole problem applies only to utility statements. Optimizable statements don't have the issue because we long ago made the executor treat Plan trees as read-only. Perhaps someday we will make utility statement execution act likewise, but I'm not holding my breath.) Discussion: https://postgr.es/m/931771.1623893989@sss.pgh.pa.us Discussion: https://postgr.es/m/17053-3ca3f501bbc212b4@postgresql.org
2021-06-18 17:22:58 +02:00
stmt->whereClause,
EXPR_KIND_WHERE,
"WHERE");
/* we have to fix its collations too */
assign_expr_collations(pstate, *whereClause);
/* this is probably dead code without add_missing_from: */
if (list_length(pstate->p_rtable) != 2) /* naughty, naughty... */
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("rule WHERE condition cannot contain references to other relations")));
/*
* 'instead nothing' rules with a qualification need a query rangetable so
* the rewrite handler can add the negated rule qualification to the
* original query. We create a query with the new command type CMD_NOTHING
* here that is treated specially by the rewrite system.
*/
if (stmt->actions == NIL)
{
Query *nothing_qry = makeNode(Query);
nothing_qry->commandType = CMD_NOTHING;
nothing_qry->rtable = pstate->p_rtable;
Rework query relation permission checking Currently, information about the permissions to be checked on relations mentioned in a query is stored in their range table entries. So the executor must scan the entire range table looking for relations that need to have permissions checked. This can make the permission checking part of the executor initialization needlessly expensive when many inheritance children are present in the range range. While the permissions need not be checked on the individual child relations, the executor still must visit every range table entry to filter them out. This commit moves the permission checking information out of the range table entries into a new plan node called RTEPermissionInfo. Every top-level (inheritance "root") RTE_RELATION entry in the range table gets one and a list of those is maintained alongside the range table. This new list is initialized by the parser when initializing the range table. The rewriter can add more entries to it as rules/views are expanded. Finally, the planner combines the lists of the individual subqueries into one flat list that is passed to the executor for checking. To make it quick to find the RTEPermissionInfo entry belonging to a given relation, RangeTblEntry gets a new Index field 'perminfoindex' that stores the corresponding RTEPermissionInfo's index in the query's list of the latter. ExecutorCheckPerms_hook has gained another List * argument; the signature is now: typedef bool (*ExecutorCheckPerms_hook_type) (List *rangeTable, List *rtePermInfos, bool ereport_on_violation); The first argument is no longer used by any in-core uses of the hook, but we leave it in place because there may be other implementations that do. Implementations should likely scan the rtePermInfos list to determine which operations to allow or deny. Author: Amit Langote <amitlangote09@gmail.com> Discussion: https://postgr.es/m/CA+HiwqGjJDmUhDSfv-U2qhKJjt9ST7Xh9JXC_irsAQ1TAUsJYg@mail.gmail.com
2022-12-06 16:09:24 +01:00
nothing_qry->rteperminfos = pstate->p_rteperminfos;
nothing_qry->jointree = makeFromExpr(NIL, NULL); /* no join wanted */
*actions = list_make1(nothing_qry);
}
else
{
ListCell *l;
List *newactions = NIL;
/*
* transform each statement, like parse_sub_analyze()
*/
foreach(l, stmt->actions)
{
Node *action = (Node *) lfirst(l);
ParseState *sub_pstate = make_parsestate(NULL);
Query *sub_qry,
*top_subqry;
bool has_old,
has_new;
/*
* Since outer ParseState isn't parent of inner, have to pass down
* the query text by hand.
*/
sub_pstate->p_sourcetext = queryString;
/*
* Set up OLD/NEW in the rtable for this statement. The entries
* are added only to relnamespace, not varnamespace, because we
* don't want them to be referred to by unqualified field names
* nor "*" in the rule actions. We decide later whether to put
* them in the joinlist.
*/
Make parser rely more heavily on the ParseNamespaceItem data structure. When I added the ParseNamespaceItem data structure (in commit 5ebaaa494), it wasn't very tightly integrated into the parser's APIs. In the wake of adding p_rtindex to that struct (commit b541e9acc), there is a good reason to make more use of it: by passing around ParseNamespaceItem pointers instead of bare RTE pointers, we can get rid of various messy methods for passing back or deducing the rangetable index of an RTE during parsing. Hence, refactor the addRangeTableEntryXXX functions to build and return a ParseNamespaceItem struct, not just the RTE proper; and replace addRTEtoQuery with addNSItemToQuery, which is passed a ParseNamespaceItem rather than building one internally. Also, add per-column data (a ParseNamespaceColumn array) to each ParseNamespaceItem. These arrays are built during addRangeTableEntryXXX, where we have column type data at hand so that it's nearly free to fill the data structure. Later, when we need to build Vars referencing RTEs, we can use the ParseNamespaceColumn info to avoid the rather expensive operations done in get_rte_attribute_type() or expandRTE(). get_rte_attribute_type() is indeed dead code now, so I've removed it. This makes for a useful improvement in parse analysis speed, around 20% in one moderately-complex test query. The ParseNamespaceColumn structs also include Var identity information (varno/varattno). That info isn't actually being used in this patch, except that p_varno == 0 is a handy test for a dropped column. A follow-on patch will make more use of it. Discussion: https://postgr.es/m/2461.1577764221@sss.pgh.pa.us
2020-01-02 17:29:01 +01:00
oldnsitem = addRangeTableEntryForRelation(sub_pstate, rel,
AccessShareLock,
makeAlias("old", NIL),
false, false);
newnsitem = addRangeTableEntryForRelation(sub_pstate, rel,
AccessShareLock,
makeAlias("new", NIL),
false, false);
addNSItemToQuery(sub_pstate, oldnsitem, false, true, false);
addNSItemToQuery(sub_pstate, newnsitem, false, true, false);
/* Transform the rule action statement */
Centralize the logic for protective copying of utility statements. In the "simple Query" code path, it's fine for parse analysis or execution of a utility statement to scribble on the statement's node tree, since that'll just be thrown away afterwards. However it's not fine if the node tree is in the plan cache, as then it'd be corrupted for subsequent executions. Up to now we've dealt with that by having individual utility-statement functions apply copyObject() if they were going to modify the tree. But that's prone to errors of omission. Bug #17053 from Charles Samborski shows that CREATE/ALTER DOMAIN didn't get this memo, and can crash if executed repeatedly from plan cache. In the back branches, we'll just apply a narrow band-aid for that, but in HEAD it seems prudent to have a more principled fix that will close off the possibility of other similar bugs in future. Hence, let's hoist the responsibility for doing copyObject up into ProcessUtility from its children, thus ensuring that it happens for all utility statement types. Also, modify ProcessUtility's API so that its callers can tell it whether a copy step is necessary. It turns out that in all cases, the immediate caller knows whether the node tree is transient, so this doesn't involve a huge amount of code thrashing. In this way, while we lose a little bit in the execute-from-cache code path due to sometimes copying node trees that wouldn't be mutated anyway, we gain something in the simple-Query code path by not copying throwaway node trees. Statements that are complex enough to be expensive to copy are almost certainly ones that would have to be copied anyway, so the loss in the cache code path shouldn't be much. (Note that this whole problem applies only to utility statements. Optimizable statements don't have the issue because we long ago made the executor treat Plan trees as read-only. Perhaps someday we will make utility statement execution act likewise, but I'm not holding my breath.) Discussion: https://postgr.es/m/931771.1623893989@sss.pgh.pa.us Discussion: https://postgr.es/m/17053-3ca3f501bbc212b4@postgresql.org
2021-06-18 17:22:58 +02:00
top_subqry = transformStmt(sub_pstate, action);
/*
* We cannot support utility-statement actions (eg NOTIFY) with
* nonempty rule WHERE conditions, because there's no way to make
* the utility action execute conditionally.
*/
if (top_subqry->commandType == CMD_UTILITY &&
*whereClause != NULL)
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("rules with WHERE conditions can only have SELECT, INSERT, UPDATE, or DELETE actions")));
/*
* If the action is INSERT...SELECT, OLD/NEW have been pushed down
* into the SELECT, and that's what we need to look at. (Ugly
* kluge ... try to fix this when we redesign querytrees.)
*/
sub_qry = getInsertSelectQuery(top_subqry, NULL);
/*
* If the sub_qry is a setop, we cannot attach any qualifications
* to it, because the planner won't notice them. This could
* perhaps be relaxed someday, but for now, we may as well reject
* such a rule immediately.
*/
if (sub_qry->setOperations != NULL && *whereClause != NULL)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("conditional UNION/INTERSECT/EXCEPT statements are not implemented")));
/*
* Validate action's use of OLD/NEW, qual too
*/
has_old =
rangeTableEntry_used((Node *) sub_qry, PRS2_OLD_VARNO, 0) ||
rangeTableEntry_used(*whereClause, PRS2_OLD_VARNO, 0);
has_new =
rangeTableEntry_used((Node *) sub_qry, PRS2_NEW_VARNO, 0) ||
rangeTableEntry_used(*whereClause, PRS2_NEW_VARNO, 0);
switch (stmt->event)
{
case CMD_SELECT:
if (has_old)
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("ON SELECT rule cannot use OLD")));
if (has_new)
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("ON SELECT rule cannot use NEW")));
break;
case CMD_UPDATE:
/* both are OK */
break;
case CMD_INSERT:
if (has_old)
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("ON INSERT rule cannot use OLD")));
break;
case CMD_DELETE:
if (has_new)
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("ON DELETE rule cannot use NEW")));
break;
default:
elog(ERROR, "unrecognized event type: %d",
(int) stmt->event);
break;
}
/*
* OLD/NEW are not allowed in WITH queries, because they would
* amount to outer references for the WITH, which we disallow.
* However, they were already in the outer rangetable when we
* analyzed the query, so we have to check.
*
* Note that in the INSERT...SELECT case, we need to examine the
* CTE lists of both top_subqry and sub_qry.
*
* Note that we aren't digging into the body of the query looking
* for WITHs in nested sub-SELECTs. A WITH down there can
* legitimately refer to OLD/NEW, because it'd be an
* indirect-correlated outer reference.
*/
if (rangeTableEntry_used((Node *) top_subqry->cteList,
PRS2_OLD_VARNO, 0) ||
rangeTableEntry_used((Node *) sub_qry->cteList,
PRS2_OLD_VARNO, 0))
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot refer to OLD within WITH query")));
if (rangeTableEntry_used((Node *) top_subqry->cteList,
PRS2_NEW_VARNO, 0) ||
rangeTableEntry_used((Node *) sub_qry->cteList,
PRS2_NEW_VARNO, 0))
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot refer to NEW within WITH query")));
/*
* For efficiency's sake, add OLD to the rule action's jointree
* only if it was actually referenced in the statement or qual.
*
* For INSERT, NEW is not really a relation (only a reference to
* the to-be-inserted tuple) and should never be added to the
* jointree.
*
* For UPDATE, we treat NEW as being another kind of reference to
* OLD, because it represents references to *transformed* tuples
* of the existing relation. It would be wrong to enter NEW
* separately in the jointree, since that would cause a double
* join of the updated relation. It's also wrong to fail to make
* a jointree entry if only NEW and not OLD is mentioned.
*/
if (has_old || (has_new && stmt->event == CMD_UPDATE))
{
Make parser rely more heavily on the ParseNamespaceItem data structure. When I added the ParseNamespaceItem data structure (in commit 5ebaaa494), it wasn't very tightly integrated into the parser's APIs. In the wake of adding p_rtindex to that struct (commit b541e9acc), there is a good reason to make more use of it: by passing around ParseNamespaceItem pointers instead of bare RTE pointers, we can get rid of various messy methods for passing back or deducing the rangetable index of an RTE during parsing. Hence, refactor the addRangeTableEntryXXX functions to build and return a ParseNamespaceItem struct, not just the RTE proper; and replace addRTEtoQuery with addNSItemToQuery, which is passed a ParseNamespaceItem rather than building one internally. Also, add per-column data (a ParseNamespaceColumn array) to each ParseNamespaceItem. These arrays are built during addRangeTableEntryXXX, where we have column type data at hand so that it's nearly free to fill the data structure. Later, when we need to build Vars referencing RTEs, we can use the ParseNamespaceColumn info to avoid the rather expensive operations done in get_rte_attribute_type() or expandRTE(). get_rte_attribute_type() is indeed dead code now, so I've removed it. This makes for a useful improvement in parse analysis speed, around 20% in one moderately-complex test query. The ParseNamespaceColumn structs also include Var identity information (varno/varattno). That info isn't actually being used in this patch, except that p_varno == 0 is a handy test for a dropped column. A follow-on patch will make more use of it. Discussion: https://postgr.es/m/2461.1577764221@sss.pgh.pa.us
2020-01-02 17:29:01 +01:00
RangeTblRef *rtr;
/*
* If sub_qry is a setop, manipulating its jointree will do no
* good at all, because the jointree is dummy. (This should be
* a can't-happen case because of prior tests.)
*/
if (sub_qry->setOperations != NULL)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("conditional UNION/INTERSECT/EXCEPT statements are not implemented")));
Make parser rely more heavily on the ParseNamespaceItem data structure. When I added the ParseNamespaceItem data structure (in commit 5ebaaa494), it wasn't very tightly integrated into the parser's APIs. In the wake of adding p_rtindex to that struct (commit b541e9acc), there is a good reason to make more use of it: by passing around ParseNamespaceItem pointers instead of bare RTE pointers, we can get rid of various messy methods for passing back or deducing the rangetable index of an RTE during parsing. Hence, refactor the addRangeTableEntryXXX functions to build and return a ParseNamespaceItem struct, not just the RTE proper; and replace addRTEtoQuery with addNSItemToQuery, which is passed a ParseNamespaceItem rather than building one internally. Also, add per-column data (a ParseNamespaceColumn array) to each ParseNamespaceItem. These arrays are built during addRangeTableEntryXXX, where we have column type data at hand so that it's nearly free to fill the data structure. Later, when we need to build Vars referencing RTEs, we can use the ParseNamespaceColumn info to avoid the rather expensive operations done in get_rte_attribute_type() or expandRTE(). get_rte_attribute_type() is indeed dead code now, so I've removed it. This makes for a useful improvement in parse analysis speed, around 20% in one moderately-complex test query. The ParseNamespaceColumn structs also include Var identity information (varno/varattno). That info isn't actually being used in this patch, except that p_varno == 0 is a handy test for a dropped column. A follow-on patch will make more use of it. Discussion: https://postgr.es/m/2461.1577764221@sss.pgh.pa.us
2020-01-02 17:29:01 +01:00
/* hackishly add OLD to the already-built FROM clause */
rtr = makeNode(RangeTblRef);
rtr->rtindex = oldnsitem->p_rtindex;
sub_qry->jointree->fromlist =
lappend(sub_qry->jointree->fromlist, rtr);
}
newactions = lappend(newactions, top_subqry);
free_parsestate(sub_pstate);
}
*actions = newactions;
}
free_parsestate(pstate);
/* Close relation, but keep the exclusive lock */
table_close(rel, NoLock);
}
/*
* transformAlterTableStmt -
* parse analysis for ALTER TABLE
*
Restructure ALTER TABLE execution to fix assorted bugs. We've had numerous bug reports about how (1) IF NOT EXISTS clauses in ALTER TABLE don't behave as-expected, and (2) combining certain actions into one ALTER TABLE doesn't work, though executing the same actions as separate statements does. This patch cleans up all of the cases so far reported from the field, though there are still some oddities associated with identity columns. The core problem behind all of these bugs is that we do parse analysis of ALTER TABLE subcommands too soon, before starting execution of the statement. The root of the bugs in group (1) is that parse analysis schedules derived commands (such as a CREATE SEQUENCE for a serial column) before it's known whether the IF NOT EXISTS clause should cause a subcommand to be skipped. The root of the bugs in group (2) is that earlier subcommands may change the catalog state that later subcommands need to be parsed against. Hence, postpone parse analysis of ALTER TABLE's subcommands, and do that one subcommand at a time, during "phase 2" of ALTER TABLE which is the phase that does catalog rewrites. Thus the catalog effects of earlier subcommands are already visible when we analyze later ones. (The sole exception is that we do parse analysis for ALTER COLUMN TYPE subcommands during phase 1, so that their USING expressions can be parsed against the table's original state, which is what we need. Arguably, these bugs stem from falsely concluding that because ALTER COLUMN TYPE must do early parse analysis, every other command subtype can too.) This means that ALTER TABLE itself must deal with execution of any non-ALTER-TABLE derived statements that are generated by parse analysis. Add a suitable entry point to utility.c to accept those recursive calls, and create a struct to pass through the information needed by the recursive call, rather than making the argument lists of AlterTable() and friends even longer. Getting this to work correctly required a little bit of fiddling with the subcommand pass structure, in particular breaking up AT_PASS_ADD_CONSTR into multiple passes. But otherwise it's mostly a pretty straightforward application of the above ideas. Fixing the residual issues for identity columns requires refactoring of where the dependency link from an identity column to its sequence gets set up. So that seems like suitable material for a separate patch, especially since this one is pretty big already. Discussion: https://postgr.es/m/10365.1558909428@sss.pgh.pa.us
2020-01-16 00:49:24 +01:00
* Returns the transformed AlterTableStmt. There may be additional actions
* to be done before and after the transformed statement, which are returned
* in *beforeStmts and *afterStmts as lists of utility command parsetrees.
*
* To avoid race conditions, it's important that this function rely only on
* the passed-in relid (and not on stmt->relation) to determine the target
* relation.
*/
Restructure ALTER TABLE execution to fix assorted bugs. We've had numerous bug reports about how (1) IF NOT EXISTS clauses in ALTER TABLE don't behave as-expected, and (2) combining certain actions into one ALTER TABLE doesn't work, though executing the same actions as separate statements does. This patch cleans up all of the cases so far reported from the field, though there are still some oddities associated with identity columns. The core problem behind all of these bugs is that we do parse analysis of ALTER TABLE subcommands too soon, before starting execution of the statement. The root of the bugs in group (1) is that parse analysis schedules derived commands (such as a CREATE SEQUENCE for a serial column) before it's known whether the IF NOT EXISTS clause should cause a subcommand to be skipped. The root of the bugs in group (2) is that earlier subcommands may change the catalog state that later subcommands need to be parsed against. Hence, postpone parse analysis of ALTER TABLE's subcommands, and do that one subcommand at a time, during "phase 2" of ALTER TABLE which is the phase that does catalog rewrites. Thus the catalog effects of earlier subcommands are already visible when we analyze later ones. (The sole exception is that we do parse analysis for ALTER COLUMN TYPE subcommands during phase 1, so that their USING expressions can be parsed against the table's original state, which is what we need. Arguably, these bugs stem from falsely concluding that because ALTER COLUMN TYPE must do early parse analysis, every other command subtype can too.) This means that ALTER TABLE itself must deal with execution of any non-ALTER-TABLE derived statements that are generated by parse analysis. Add a suitable entry point to utility.c to accept those recursive calls, and create a struct to pass through the information needed by the recursive call, rather than making the argument lists of AlterTable() and friends even longer. Getting this to work correctly required a little bit of fiddling with the subcommand pass structure, in particular breaking up AT_PASS_ADD_CONSTR into multiple passes. But otherwise it's mostly a pretty straightforward application of the above ideas. Fixing the residual issues for identity columns requires refactoring of where the dependency link from an identity column to its sequence gets set up. So that seems like suitable material for a separate patch, especially since this one is pretty big already. Discussion: https://postgr.es/m/10365.1558909428@sss.pgh.pa.us
2020-01-16 00:49:24 +01:00
AlterTableStmt *
transformAlterTableStmt(Oid relid, AlterTableStmt *stmt,
Restructure ALTER TABLE execution to fix assorted bugs. We've had numerous bug reports about how (1) IF NOT EXISTS clauses in ALTER TABLE don't behave as-expected, and (2) combining certain actions into one ALTER TABLE doesn't work, though executing the same actions as separate statements does. This patch cleans up all of the cases so far reported from the field, though there are still some oddities associated with identity columns. The core problem behind all of these bugs is that we do parse analysis of ALTER TABLE subcommands too soon, before starting execution of the statement. The root of the bugs in group (1) is that parse analysis schedules derived commands (such as a CREATE SEQUENCE for a serial column) before it's known whether the IF NOT EXISTS clause should cause a subcommand to be skipped. The root of the bugs in group (2) is that earlier subcommands may change the catalog state that later subcommands need to be parsed against. Hence, postpone parse analysis of ALTER TABLE's subcommands, and do that one subcommand at a time, during "phase 2" of ALTER TABLE which is the phase that does catalog rewrites. Thus the catalog effects of earlier subcommands are already visible when we analyze later ones. (The sole exception is that we do parse analysis for ALTER COLUMN TYPE subcommands during phase 1, so that their USING expressions can be parsed against the table's original state, which is what we need. Arguably, these bugs stem from falsely concluding that because ALTER COLUMN TYPE must do early parse analysis, every other command subtype can too.) This means that ALTER TABLE itself must deal with execution of any non-ALTER-TABLE derived statements that are generated by parse analysis. Add a suitable entry point to utility.c to accept those recursive calls, and create a struct to pass through the information needed by the recursive call, rather than making the argument lists of AlterTable() and friends even longer. Getting this to work correctly required a little bit of fiddling with the subcommand pass structure, in particular breaking up AT_PASS_ADD_CONSTR into multiple passes. But otherwise it's mostly a pretty straightforward application of the above ideas. Fixing the residual issues for identity columns requires refactoring of where the dependency link from an identity column to its sequence gets set up. So that seems like suitable material for a separate patch, especially since this one is pretty big already. Discussion: https://postgr.es/m/10365.1558909428@sss.pgh.pa.us
2020-01-16 00:49:24 +01:00
const char *queryString,
List **beforeStmts, List **afterStmts)
{
Relation rel;
TupleDesc tupdesc;
ParseState *pstate;
CreateStmtContext cxt;
List *save_alist;
ListCell *lcmd,
*l;
List *newcmds = NIL;
bool skipValidation = true;
AlterTableCmd *newcmd;
Make parser rely more heavily on the ParseNamespaceItem data structure. When I added the ParseNamespaceItem data structure (in commit 5ebaaa494), it wasn't very tightly integrated into the parser's APIs. In the wake of adding p_rtindex to that struct (commit b541e9acc), there is a good reason to make more use of it: by passing around ParseNamespaceItem pointers instead of bare RTE pointers, we can get rid of various messy methods for passing back or deducing the rangetable index of an RTE during parsing. Hence, refactor the addRangeTableEntryXXX functions to build and return a ParseNamespaceItem struct, not just the RTE proper; and replace addRTEtoQuery with addNSItemToQuery, which is passed a ParseNamespaceItem rather than building one internally. Also, add per-column data (a ParseNamespaceColumn array) to each ParseNamespaceItem. These arrays are built during addRangeTableEntryXXX, where we have column type data at hand so that it's nearly free to fill the data structure. Later, when we need to build Vars referencing RTEs, we can use the ParseNamespaceColumn info to avoid the rather expensive operations done in get_rte_attribute_type() or expandRTE(). get_rte_attribute_type() is indeed dead code now, so I've removed it. This makes for a useful improvement in parse analysis speed, around 20% in one moderately-complex test query. The ParseNamespaceColumn structs also include Var identity information (varno/varattno). That info isn't actually being used in this patch, except that p_varno == 0 is a handy test for a dropped column. A follow-on patch will make more use of it. Discussion: https://postgr.es/m/2461.1577764221@sss.pgh.pa.us
2020-01-02 17:29:01 +01:00
ParseNamespaceItem *nsitem;
/* Caller is responsible for locking the relation */
rel = relation_open(relid, NoLock);
tupdesc = RelationGetDescr(rel);
/* Set up pstate */
pstate = make_parsestate(NULL);
pstate->p_sourcetext = queryString;
Make parser rely more heavily on the ParseNamespaceItem data structure. When I added the ParseNamespaceItem data structure (in commit 5ebaaa494), it wasn't very tightly integrated into the parser's APIs. In the wake of adding p_rtindex to that struct (commit b541e9acc), there is a good reason to make more use of it: by passing around ParseNamespaceItem pointers instead of bare RTE pointers, we can get rid of various messy methods for passing back or deducing the rangetable index of an RTE during parsing. Hence, refactor the addRangeTableEntryXXX functions to build and return a ParseNamespaceItem struct, not just the RTE proper; and replace addRTEtoQuery with addNSItemToQuery, which is passed a ParseNamespaceItem rather than building one internally. Also, add per-column data (a ParseNamespaceColumn array) to each ParseNamespaceItem. These arrays are built during addRangeTableEntryXXX, where we have column type data at hand so that it's nearly free to fill the data structure. Later, when we need to build Vars referencing RTEs, we can use the ParseNamespaceColumn info to avoid the rather expensive operations done in get_rte_attribute_type() or expandRTE(). get_rte_attribute_type() is indeed dead code now, so I've removed it. This makes for a useful improvement in parse analysis speed, around 20% in one moderately-complex test query. The ParseNamespaceColumn structs also include Var identity information (varno/varattno). That info isn't actually being used in this patch, except that p_varno == 0 is a handy test for a dropped column. A follow-on patch will make more use of it. Discussion: https://postgr.es/m/2461.1577764221@sss.pgh.pa.us
2020-01-02 17:29:01 +01:00
nsitem = addRangeTableEntryForRelation(pstate,
rel,
AccessShareLock,
NULL,
false,
true);
addNSItemToQuery(pstate, nsitem, false, true, true);
/* Set up CreateStmtContext */
cxt.pstate = pstate;
Restructure ALTER TABLE execution to fix assorted bugs. We've had numerous bug reports about how (1) IF NOT EXISTS clauses in ALTER TABLE don't behave as-expected, and (2) combining certain actions into one ALTER TABLE doesn't work, though executing the same actions as separate statements does. This patch cleans up all of the cases so far reported from the field, though there are still some oddities associated with identity columns. The core problem behind all of these bugs is that we do parse analysis of ALTER TABLE subcommands too soon, before starting execution of the statement. The root of the bugs in group (1) is that parse analysis schedules derived commands (such as a CREATE SEQUENCE for a serial column) before it's known whether the IF NOT EXISTS clause should cause a subcommand to be skipped. The root of the bugs in group (2) is that earlier subcommands may change the catalog state that later subcommands need to be parsed against. Hence, postpone parse analysis of ALTER TABLE's subcommands, and do that one subcommand at a time, during "phase 2" of ALTER TABLE which is the phase that does catalog rewrites. Thus the catalog effects of earlier subcommands are already visible when we analyze later ones. (The sole exception is that we do parse analysis for ALTER COLUMN TYPE subcommands during phase 1, so that their USING expressions can be parsed against the table's original state, which is what we need. Arguably, these bugs stem from falsely concluding that because ALTER COLUMN TYPE must do early parse analysis, every other command subtype can too.) This means that ALTER TABLE itself must deal with execution of any non-ALTER-TABLE derived statements that are generated by parse analysis. Add a suitable entry point to utility.c to accept those recursive calls, and create a struct to pass through the information needed by the recursive call, rather than making the argument lists of AlterTable() and friends even longer. Getting this to work correctly required a little bit of fiddling with the subcommand pass structure, in particular breaking up AT_PASS_ADD_CONSTR into multiple passes. But otherwise it's mostly a pretty straightforward application of the above ideas. Fixing the residual issues for identity columns requires refactoring of where the dependency link from an identity column to its sequence gets set up. So that seems like suitable material for a separate patch, especially since this one is pretty big already. Discussion: https://postgr.es/m/10365.1558909428@sss.pgh.pa.us
2020-01-16 00:49:24 +01:00
if (rel->rd_rel->relkind == RELKIND_FOREIGN_TABLE)
{
cxt.stmtType = "ALTER FOREIGN TABLE";
cxt.isforeign = true;
}
else
{
cxt.stmtType = "ALTER TABLE";
cxt.isforeign = false;
}
cxt.relation = stmt->relation;
cxt.rel = rel;
cxt.inhRelations = NIL;
cxt.isalter = true;
cxt.columns = NIL;
cxt.ckconstraints = NIL;
cxt.fkconstraints = NIL;
cxt.ixconstraints = NIL;
cxt.likeclauses = NIL;
cxt.extstats = NIL;
cxt.blist = NIL;
cxt.alist = NIL;
cxt.pkey = NULL;
Implement table partitioning. Table partitioning is like table inheritance and reuses much of the existing infrastructure, but there are some important differences. The parent is called a partitioned table and is always empty; it may not have indexes or non-inherited constraints, since those make no sense for a relation with no data of its own. The children are called partitions and contain all of the actual data. Each partition has an implicit partitioning constraint. Multiple inheritance is not allowed, and partitioning and inheritance can't be mixed. Partitions can't have extra columns and may not allow nulls unless the parent does. Tuples inserted into the parent are automatically routed to the correct partition, so tuple-routing ON INSERT triggers are not needed. Tuple routing isn't yet supported for partitions which are foreign tables, and it doesn't handle updates that cross partition boundaries. Currently, tables can be range-partitioned or list-partitioned. List partitioning is limited to a single column, but range partitioning can involve multiple columns. A partitioning "column" can be an expression. Because table partitioning is less general than table inheritance, it is hoped that it will be easier to reason about properties of partitions, and therefore that this will serve as a better foundation for a variety of possible optimizations, including query planner optimizations. The tuple routing based which this patch does based on the implicit partitioning constraints is an example of this, but it seems likely that many other useful optimizations are also possible. Amit Langote, reviewed and tested by Robert Haas, Ashutosh Bapat, Amit Kapila, Rajkumar Raghuwanshi, Corey Huinker, Jaime Casanova, Rushabh Lathia, Erik Rijkers, among others. Minor revisions by me.
2016-12-07 19:17:43 +01:00
cxt.ispartitioned = (rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE);
cxt.partbound = NULL;
cxt.ofType = false;
/*
Restructure ALTER TABLE execution to fix assorted bugs. We've had numerous bug reports about how (1) IF NOT EXISTS clauses in ALTER TABLE don't behave as-expected, and (2) combining certain actions into one ALTER TABLE doesn't work, though executing the same actions as separate statements does. This patch cleans up all of the cases so far reported from the field, though there are still some oddities associated with identity columns. The core problem behind all of these bugs is that we do parse analysis of ALTER TABLE subcommands too soon, before starting execution of the statement. The root of the bugs in group (1) is that parse analysis schedules derived commands (such as a CREATE SEQUENCE for a serial column) before it's known whether the IF NOT EXISTS clause should cause a subcommand to be skipped. The root of the bugs in group (2) is that earlier subcommands may change the catalog state that later subcommands need to be parsed against. Hence, postpone parse analysis of ALTER TABLE's subcommands, and do that one subcommand at a time, during "phase 2" of ALTER TABLE which is the phase that does catalog rewrites. Thus the catalog effects of earlier subcommands are already visible when we analyze later ones. (The sole exception is that we do parse analysis for ALTER COLUMN TYPE subcommands during phase 1, so that their USING expressions can be parsed against the table's original state, which is what we need. Arguably, these bugs stem from falsely concluding that because ALTER COLUMN TYPE must do early parse analysis, every other command subtype can too.) This means that ALTER TABLE itself must deal with execution of any non-ALTER-TABLE derived statements that are generated by parse analysis. Add a suitable entry point to utility.c to accept those recursive calls, and create a struct to pass through the information needed by the recursive call, rather than making the argument lists of AlterTable() and friends even longer. Getting this to work correctly required a little bit of fiddling with the subcommand pass structure, in particular breaking up AT_PASS_ADD_CONSTR into multiple passes. But otherwise it's mostly a pretty straightforward application of the above ideas. Fixing the residual issues for identity columns requires refactoring of where the dependency link from an identity column to its sequence gets set up. So that seems like suitable material for a separate patch, especially since this one is pretty big already. Discussion: https://postgr.es/m/10365.1558909428@sss.pgh.pa.us
2020-01-16 00:49:24 +01:00
* Transform ALTER subcommands that need it (most don't). These largely
* re-use code from CREATE TABLE.
*/
foreach(lcmd, stmt->cmds)
{
AlterTableCmd *cmd = (AlterTableCmd *) lfirst(lcmd);
switch (cmd->subtype)
{
case AT_AddColumn:
{
2017-02-21 17:33:07 +01:00
ColumnDef *def = castNode(ColumnDef, cmd->def);
transformColumnDefinition(&cxt, def);
/*
* If the column has a non-null default, we can't skip
* validation of foreign keys.
*/
if (def->raw_default != NULL)
skipValidation = false;
/*
* All constraints are processed in other ways. Remove the
* original list
*/
def->constraints = NIL;
newcmds = lappend(newcmds, cmd);
break;
}
case AT_AddConstraint:
/*
* The original AddConstraint cmd node doesn't go to newcmds
*/
if (IsA(cmd->def, Constraint))
{
transformTableConstraint(&cxt, (Constraint *) cmd->def);
if (((Constraint *) cmd->def)->contype == CONSTR_FOREIGN)
skipValidation = false;
}
else
elog(ERROR, "unrecognized node type: %d",
(int) nodeTag(cmd->def));
break;
case AT_AlterColumnType:
{
Restructure ALTER TABLE execution to fix assorted bugs. We've had numerous bug reports about how (1) IF NOT EXISTS clauses in ALTER TABLE don't behave as-expected, and (2) combining certain actions into one ALTER TABLE doesn't work, though executing the same actions as separate statements does. This patch cleans up all of the cases so far reported from the field, though there are still some oddities associated with identity columns. The core problem behind all of these bugs is that we do parse analysis of ALTER TABLE subcommands too soon, before starting execution of the statement. The root of the bugs in group (1) is that parse analysis schedules derived commands (such as a CREATE SEQUENCE for a serial column) before it's known whether the IF NOT EXISTS clause should cause a subcommand to be skipped. The root of the bugs in group (2) is that earlier subcommands may change the catalog state that later subcommands need to be parsed against. Hence, postpone parse analysis of ALTER TABLE's subcommands, and do that one subcommand at a time, during "phase 2" of ALTER TABLE which is the phase that does catalog rewrites. Thus the catalog effects of earlier subcommands are already visible when we analyze later ones. (The sole exception is that we do parse analysis for ALTER COLUMN TYPE subcommands during phase 1, so that their USING expressions can be parsed against the table's original state, which is what we need. Arguably, these bugs stem from falsely concluding that because ALTER COLUMN TYPE must do early parse analysis, every other command subtype can too.) This means that ALTER TABLE itself must deal with execution of any non-ALTER-TABLE derived statements that are generated by parse analysis. Add a suitable entry point to utility.c to accept those recursive calls, and create a struct to pass through the information needed by the recursive call, rather than making the argument lists of AlterTable() and friends even longer. Getting this to work correctly required a little bit of fiddling with the subcommand pass structure, in particular breaking up AT_PASS_ADD_CONSTR into multiple passes. But otherwise it's mostly a pretty straightforward application of the above ideas. Fixing the residual issues for identity columns requires refactoring of where the dependency link from an identity column to its sequence gets set up. So that seems like suitable material for a separate patch, especially since this one is pretty big already. Discussion: https://postgr.es/m/10365.1558909428@sss.pgh.pa.us
2020-01-16 00:49:24 +01:00
ColumnDef *def = castNode(ColumnDef, cmd->def);
AttrNumber attnum;
/*
* For ALTER COLUMN TYPE, transform the USING clause if
* one was specified.
*/
if (def->raw_default)
{
def->cooked_default =
transformExpr(pstate, def->raw_default,
EXPR_KIND_ALTER_COL_TRANSFORM);
}
/*
* For identity column, create ALTER SEQUENCE command to
* change the data type of the sequence.
*/
attnum = get_attnum(relid, cmd->name);
Restructure ALTER TABLE execution to fix assorted bugs. We've had numerous bug reports about how (1) IF NOT EXISTS clauses in ALTER TABLE don't behave as-expected, and (2) combining certain actions into one ALTER TABLE doesn't work, though executing the same actions as separate statements does. This patch cleans up all of the cases so far reported from the field, though there are still some oddities associated with identity columns. The core problem behind all of these bugs is that we do parse analysis of ALTER TABLE subcommands too soon, before starting execution of the statement. The root of the bugs in group (1) is that parse analysis schedules derived commands (such as a CREATE SEQUENCE for a serial column) before it's known whether the IF NOT EXISTS clause should cause a subcommand to be skipped. The root of the bugs in group (2) is that earlier subcommands may change the catalog state that later subcommands need to be parsed against. Hence, postpone parse analysis of ALTER TABLE's subcommands, and do that one subcommand at a time, during "phase 2" of ALTER TABLE which is the phase that does catalog rewrites. Thus the catalog effects of earlier subcommands are already visible when we analyze later ones. (The sole exception is that we do parse analysis for ALTER COLUMN TYPE subcommands during phase 1, so that their USING expressions can be parsed against the table's original state, which is what we need. Arguably, these bugs stem from falsely concluding that because ALTER COLUMN TYPE must do early parse analysis, every other command subtype can too.) This means that ALTER TABLE itself must deal with execution of any non-ALTER-TABLE derived statements that are generated by parse analysis. Add a suitable entry point to utility.c to accept those recursive calls, and create a struct to pass through the information needed by the recursive call, rather than making the argument lists of AlterTable() and friends even longer. Getting this to work correctly required a little bit of fiddling with the subcommand pass structure, in particular breaking up AT_PASS_ADD_CONSTR into multiple passes. But otherwise it's mostly a pretty straightforward application of the above ideas. Fixing the residual issues for identity columns requires refactoring of where the dependency link from an identity column to its sequence gets set up. So that seems like suitable material for a separate patch, especially since this one is pretty big already. Discussion: https://postgr.es/m/10365.1558909428@sss.pgh.pa.us
2020-01-16 00:49:24 +01:00
if (attnum == InvalidAttrNumber)
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_COLUMN),
errmsg("column \"%s\" of relation \"%s\" does not exist",
cmd->name, RelationGetRelationName(rel))));
if (attnum > 0 &&
TupleDescAttr(tupdesc, attnum - 1)->attidentity)
{
Oid seq_relid = getIdentitySequence(relid, attnum, false);
Oid typeOid = typenameTypeId(pstate, def->typeName);
AlterSeqStmt *altseqstmt = makeNode(AlterSeqStmt);
altseqstmt->sequence = makeRangeVar(get_namespace_name(get_rel_namespace(seq_relid)),
get_rel_name(seq_relid),
-1);
altseqstmt->options = list_make1(makeDefElem("as", (Node *) makeTypeNameFromOid(typeOid, -1), -1));
altseqstmt->for_identity = true;
cxt.blist = lappend(cxt.blist, altseqstmt);
}
newcmds = lappend(newcmds, cmd);
break;
}
case AT_AddIdentity:
{
Constraint *def = castNode(Constraint, cmd->def);
ColumnDef *newdef = makeNode(ColumnDef);
AttrNumber attnum;
newdef->colname = cmd->name;
newdef->identity = def->generated_when;
cmd->def = (Node *) newdef;
attnum = get_attnum(relid, cmd->name);
Restructure ALTER TABLE execution to fix assorted bugs. We've had numerous bug reports about how (1) IF NOT EXISTS clauses in ALTER TABLE don't behave as-expected, and (2) combining certain actions into one ALTER TABLE doesn't work, though executing the same actions as separate statements does. This patch cleans up all of the cases so far reported from the field, though there are still some oddities associated with identity columns. The core problem behind all of these bugs is that we do parse analysis of ALTER TABLE subcommands too soon, before starting execution of the statement. The root of the bugs in group (1) is that parse analysis schedules derived commands (such as a CREATE SEQUENCE for a serial column) before it's known whether the IF NOT EXISTS clause should cause a subcommand to be skipped. The root of the bugs in group (2) is that earlier subcommands may change the catalog state that later subcommands need to be parsed against. Hence, postpone parse analysis of ALTER TABLE's subcommands, and do that one subcommand at a time, during "phase 2" of ALTER TABLE which is the phase that does catalog rewrites. Thus the catalog effects of earlier subcommands are already visible when we analyze later ones. (The sole exception is that we do parse analysis for ALTER COLUMN TYPE subcommands during phase 1, so that their USING expressions can be parsed against the table's original state, which is what we need. Arguably, these bugs stem from falsely concluding that because ALTER COLUMN TYPE must do early parse analysis, every other command subtype can too.) This means that ALTER TABLE itself must deal with execution of any non-ALTER-TABLE derived statements that are generated by parse analysis. Add a suitable entry point to utility.c to accept those recursive calls, and create a struct to pass through the information needed by the recursive call, rather than making the argument lists of AlterTable() and friends even longer. Getting this to work correctly required a little bit of fiddling with the subcommand pass structure, in particular breaking up AT_PASS_ADD_CONSTR into multiple passes. But otherwise it's mostly a pretty straightforward application of the above ideas. Fixing the residual issues for identity columns requires refactoring of where the dependency link from an identity column to its sequence gets set up. So that seems like suitable material for a separate patch, especially since this one is pretty big already. Discussion: https://postgr.es/m/10365.1558909428@sss.pgh.pa.us
2020-01-16 00:49:24 +01:00
if (attnum == InvalidAttrNumber)
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_COLUMN),
errmsg("column \"%s\" of relation \"%s\" does not exist",
cmd->name, RelationGetRelationName(rel))));
Restructure ALTER TABLE execution to fix assorted bugs. We've had numerous bug reports about how (1) IF NOT EXISTS clauses in ALTER TABLE don't behave as-expected, and (2) combining certain actions into one ALTER TABLE doesn't work, though executing the same actions as separate statements does. This patch cleans up all of the cases so far reported from the field, though there are still some oddities associated with identity columns. The core problem behind all of these bugs is that we do parse analysis of ALTER TABLE subcommands too soon, before starting execution of the statement. The root of the bugs in group (1) is that parse analysis schedules derived commands (such as a CREATE SEQUENCE for a serial column) before it's known whether the IF NOT EXISTS clause should cause a subcommand to be skipped. The root of the bugs in group (2) is that earlier subcommands may change the catalog state that later subcommands need to be parsed against. Hence, postpone parse analysis of ALTER TABLE's subcommands, and do that one subcommand at a time, during "phase 2" of ALTER TABLE which is the phase that does catalog rewrites. Thus the catalog effects of earlier subcommands are already visible when we analyze later ones. (The sole exception is that we do parse analysis for ALTER COLUMN TYPE subcommands during phase 1, so that their USING expressions can be parsed against the table's original state, which is what we need. Arguably, these bugs stem from falsely concluding that because ALTER COLUMN TYPE must do early parse analysis, every other command subtype can too.) This means that ALTER TABLE itself must deal with execution of any non-ALTER-TABLE derived statements that are generated by parse analysis. Add a suitable entry point to utility.c to accept those recursive calls, and create a struct to pass through the information needed by the recursive call, rather than making the argument lists of AlterTable() and friends even longer. Getting this to work correctly required a little bit of fiddling with the subcommand pass structure, in particular breaking up AT_PASS_ADD_CONSTR into multiple passes. But otherwise it's mostly a pretty straightforward application of the above ideas. Fixing the residual issues for identity columns requires refactoring of where the dependency link from an identity column to its sequence gets set up. So that seems like suitable material for a separate patch, especially since this one is pretty big already. Discussion: https://postgr.es/m/10365.1558909428@sss.pgh.pa.us
2020-01-16 00:49:24 +01:00
generateSerialExtraStmts(&cxt, newdef,
get_atttype(relid, attnum),
def->options, true, true,
NULL, NULL);
newcmds = lappend(newcmds, cmd);
break;
}
case AT_SetIdentity:
{
/*
* Create an ALTER SEQUENCE statement for the internal
* sequence of the identity column.
*/
ListCell *lc;
List *newseqopts = NIL;
List *newdef = NIL;
AttrNumber attnum;
Restructure ALTER TABLE execution to fix assorted bugs. We've had numerous bug reports about how (1) IF NOT EXISTS clauses in ALTER TABLE don't behave as-expected, and (2) combining certain actions into one ALTER TABLE doesn't work, though executing the same actions as separate statements does. This patch cleans up all of the cases so far reported from the field, though there are still some oddities associated with identity columns. The core problem behind all of these bugs is that we do parse analysis of ALTER TABLE subcommands too soon, before starting execution of the statement. The root of the bugs in group (1) is that parse analysis schedules derived commands (such as a CREATE SEQUENCE for a serial column) before it's known whether the IF NOT EXISTS clause should cause a subcommand to be skipped. The root of the bugs in group (2) is that earlier subcommands may change the catalog state that later subcommands need to be parsed against. Hence, postpone parse analysis of ALTER TABLE's subcommands, and do that one subcommand at a time, during "phase 2" of ALTER TABLE which is the phase that does catalog rewrites. Thus the catalog effects of earlier subcommands are already visible when we analyze later ones. (The sole exception is that we do parse analysis for ALTER COLUMN TYPE subcommands during phase 1, so that their USING expressions can be parsed against the table's original state, which is what we need. Arguably, these bugs stem from falsely concluding that because ALTER COLUMN TYPE must do early parse analysis, every other command subtype can too.) This means that ALTER TABLE itself must deal with execution of any non-ALTER-TABLE derived statements that are generated by parse analysis. Add a suitable entry point to utility.c to accept those recursive calls, and create a struct to pass through the information needed by the recursive call, rather than making the argument lists of AlterTable() and friends even longer. Getting this to work correctly required a little bit of fiddling with the subcommand pass structure, in particular breaking up AT_PASS_ADD_CONSTR into multiple passes. But otherwise it's mostly a pretty straightforward application of the above ideas. Fixing the residual issues for identity columns requires refactoring of where the dependency link from an identity column to its sequence gets set up. So that seems like suitable material for a separate patch, especially since this one is pretty big already. Discussion: https://postgr.es/m/10365.1558909428@sss.pgh.pa.us
2020-01-16 00:49:24 +01:00
Oid seq_relid;
/*
* Split options into those handled by ALTER SEQUENCE and
* those for ALTER TABLE proper.
*/
foreach(lc, castNode(List, cmd->def))
{
DefElem *def = lfirst_node(DefElem, lc);
if (strcmp(def->defname, "generated") == 0)
newdef = lappend(newdef, def);
else
newseqopts = lappend(newseqopts, def);
}
attnum = get_attnum(relid, cmd->name);
Restructure ALTER TABLE execution to fix assorted bugs. We've had numerous bug reports about how (1) IF NOT EXISTS clauses in ALTER TABLE don't behave as-expected, and (2) combining certain actions into one ALTER TABLE doesn't work, though executing the same actions as separate statements does. This patch cleans up all of the cases so far reported from the field, though there are still some oddities associated with identity columns. The core problem behind all of these bugs is that we do parse analysis of ALTER TABLE subcommands too soon, before starting execution of the statement. The root of the bugs in group (1) is that parse analysis schedules derived commands (such as a CREATE SEQUENCE for a serial column) before it's known whether the IF NOT EXISTS clause should cause a subcommand to be skipped. The root of the bugs in group (2) is that earlier subcommands may change the catalog state that later subcommands need to be parsed against. Hence, postpone parse analysis of ALTER TABLE's subcommands, and do that one subcommand at a time, during "phase 2" of ALTER TABLE which is the phase that does catalog rewrites. Thus the catalog effects of earlier subcommands are already visible when we analyze later ones. (The sole exception is that we do parse analysis for ALTER COLUMN TYPE subcommands during phase 1, so that their USING expressions can be parsed against the table's original state, which is what we need. Arguably, these bugs stem from falsely concluding that because ALTER COLUMN TYPE must do early parse analysis, every other command subtype can too.) This means that ALTER TABLE itself must deal with execution of any non-ALTER-TABLE derived statements that are generated by parse analysis. Add a suitable entry point to utility.c to accept those recursive calls, and create a struct to pass through the information needed by the recursive call, rather than making the argument lists of AlterTable() and friends even longer. Getting this to work correctly required a little bit of fiddling with the subcommand pass structure, in particular breaking up AT_PASS_ADD_CONSTR into multiple passes. But otherwise it's mostly a pretty straightforward application of the above ideas. Fixing the residual issues for identity columns requires refactoring of where the dependency link from an identity column to its sequence gets set up. So that seems like suitable material for a separate patch, especially since this one is pretty big already. Discussion: https://postgr.es/m/10365.1558909428@sss.pgh.pa.us
2020-01-16 00:49:24 +01:00
if (attnum == InvalidAttrNumber)
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_COLUMN),
errmsg("column \"%s\" of relation \"%s\" does not exist",
cmd->name, RelationGetRelationName(rel))));
Restructure ALTER TABLE execution to fix assorted bugs. We've had numerous bug reports about how (1) IF NOT EXISTS clauses in ALTER TABLE don't behave as-expected, and (2) combining certain actions into one ALTER TABLE doesn't work, though executing the same actions as separate statements does. This patch cleans up all of the cases so far reported from the field, though there are still some oddities associated with identity columns. The core problem behind all of these bugs is that we do parse analysis of ALTER TABLE subcommands too soon, before starting execution of the statement. The root of the bugs in group (1) is that parse analysis schedules derived commands (such as a CREATE SEQUENCE for a serial column) before it's known whether the IF NOT EXISTS clause should cause a subcommand to be skipped. The root of the bugs in group (2) is that earlier subcommands may change the catalog state that later subcommands need to be parsed against. Hence, postpone parse analysis of ALTER TABLE's subcommands, and do that one subcommand at a time, during "phase 2" of ALTER TABLE which is the phase that does catalog rewrites. Thus the catalog effects of earlier subcommands are already visible when we analyze later ones. (The sole exception is that we do parse analysis for ALTER COLUMN TYPE subcommands during phase 1, so that their USING expressions can be parsed against the table's original state, which is what we need. Arguably, these bugs stem from falsely concluding that because ALTER COLUMN TYPE must do early parse analysis, every other command subtype can too.) This means that ALTER TABLE itself must deal with execution of any non-ALTER-TABLE derived statements that are generated by parse analysis. Add a suitable entry point to utility.c to accept those recursive calls, and create a struct to pass through the information needed by the recursive call, rather than making the argument lists of AlterTable() and friends even longer. Getting this to work correctly required a little bit of fiddling with the subcommand pass structure, in particular breaking up AT_PASS_ADD_CONSTR into multiple passes. But otherwise it's mostly a pretty straightforward application of the above ideas. Fixing the residual issues for identity columns requires refactoring of where the dependency link from an identity column to its sequence gets set up. So that seems like suitable material for a separate patch, especially since this one is pretty big already. Discussion: https://postgr.es/m/10365.1558909428@sss.pgh.pa.us
2020-01-16 00:49:24 +01:00
seq_relid = getIdentitySequence(relid, attnum, true);
Restructure ALTER TABLE execution to fix assorted bugs. We've had numerous bug reports about how (1) IF NOT EXISTS clauses in ALTER TABLE don't behave as-expected, and (2) combining certain actions into one ALTER TABLE doesn't work, though executing the same actions as separate statements does. This patch cleans up all of the cases so far reported from the field, though there are still some oddities associated with identity columns. The core problem behind all of these bugs is that we do parse analysis of ALTER TABLE subcommands too soon, before starting execution of the statement. The root of the bugs in group (1) is that parse analysis schedules derived commands (such as a CREATE SEQUENCE for a serial column) before it's known whether the IF NOT EXISTS clause should cause a subcommand to be skipped. The root of the bugs in group (2) is that earlier subcommands may change the catalog state that later subcommands need to be parsed against. Hence, postpone parse analysis of ALTER TABLE's subcommands, and do that one subcommand at a time, during "phase 2" of ALTER TABLE which is the phase that does catalog rewrites. Thus the catalog effects of earlier subcommands are already visible when we analyze later ones. (The sole exception is that we do parse analysis for ALTER COLUMN TYPE subcommands during phase 1, so that their USING expressions can be parsed against the table's original state, which is what we need. Arguably, these bugs stem from falsely concluding that because ALTER COLUMN TYPE must do early parse analysis, every other command subtype can too.) This means that ALTER TABLE itself must deal with execution of any non-ALTER-TABLE derived statements that are generated by parse analysis. Add a suitable entry point to utility.c to accept those recursive calls, and create a struct to pass through the information needed by the recursive call, rather than making the argument lists of AlterTable() and friends even longer. Getting this to work correctly required a little bit of fiddling with the subcommand pass structure, in particular breaking up AT_PASS_ADD_CONSTR into multiple passes. But otherwise it's mostly a pretty straightforward application of the above ideas. Fixing the residual issues for identity columns requires refactoring of where the dependency link from an identity column to its sequence gets set up. So that seems like suitable material for a separate patch, especially since this one is pretty big already. Discussion: https://postgr.es/m/10365.1558909428@sss.pgh.pa.us
2020-01-16 00:49:24 +01:00
if (seq_relid)
{
AlterSeqStmt *seqstmt;
Restructure ALTER TABLE execution to fix assorted bugs. We've had numerous bug reports about how (1) IF NOT EXISTS clauses in ALTER TABLE don't behave as-expected, and (2) combining certain actions into one ALTER TABLE doesn't work, though executing the same actions as separate statements does. This patch cleans up all of the cases so far reported from the field, though there are still some oddities associated with identity columns. The core problem behind all of these bugs is that we do parse analysis of ALTER TABLE subcommands too soon, before starting execution of the statement. The root of the bugs in group (1) is that parse analysis schedules derived commands (such as a CREATE SEQUENCE for a serial column) before it's known whether the IF NOT EXISTS clause should cause a subcommand to be skipped. The root of the bugs in group (2) is that earlier subcommands may change the catalog state that later subcommands need to be parsed against. Hence, postpone parse analysis of ALTER TABLE's subcommands, and do that one subcommand at a time, during "phase 2" of ALTER TABLE which is the phase that does catalog rewrites. Thus the catalog effects of earlier subcommands are already visible when we analyze later ones. (The sole exception is that we do parse analysis for ALTER COLUMN TYPE subcommands during phase 1, so that their USING expressions can be parsed against the table's original state, which is what we need. Arguably, these bugs stem from falsely concluding that because ALTER COLUMN TYPE must do early parse analysis, every other command subtype can too.) This means that ALTER TABLE itself must deal with execution of any non-ALTER-TABLE derived statements that are generated by parse analysis. Add a suitable entry point to utility.c to accept those recursive calls, and create a struct to pass through the information needed by the recursive call, rather than making the argument lists of AlterTable() and friends even longer. Getting this to work correctly required a little bit of fiddling with the subcommand pass structure, in particular breaking up AT_PASS_ADD_CONSTR into multiple passes. But otherwise it's mostly a pretty straightforward application of the above ideas. Fixing the residual issues for identity columns requires refactoring of where the dependency link from an identity column to its sequence gets set up. So that seems like suitable material for a separate patch, especially since this one is pretty big already. Discussion: https://postgr.es/m/10365.1558909428@sss.pgh.pa.us
2020-01-16 00:49:24 +01:00
seqstmt = makeNode(AlterSeqStmt);
seqstmt->sequence = makeRangeVar(get_namespace_name(get_rel_namespace(seq_relid)),
get_rel_name(seq_relid), -1);
seqstmt->options = newseqopts;
seqstmt->for_identity = true;
seqstmt->missing_ok = false;
Restructure ALTER TABLE execution to fix assorted bugs. We've had numerous bug reports about how (1) IF NOT EXISTS clauses in ALTER TABLE don't behave as-expected, and (2) combining certain actions into one ALTER TABLE doesn't work, though executing the same actions as separate statements does. This patch cleans up all of the cases so far reported from the field, though there are still some oddities associated with identity columns. The core problem behind all of these bugs is that we do parse analysis of ALTER TABLE subcommands too soon, before starting execution of the statement. The root of the bugs in group (1) is that parse analysis schedules derived commands (such as a CREATE SEQUENCE for a serial column) before it's known whether the IF NOT EXISTS clause should cause a subcommand to be skipped. The root of the bugs in group (2) is that earlier subcommands may change the catalog state that later subcommands need to be parsed against. Hence, postpone parse analysis of ALTER TABLE's subcommands, and do that one subcommand at a time, during "phase 2" of ALTER TABLE which is the phase that does catalog rewrites. Thus the catalog effects of earlier subcommands are already visible when we analyze later ones. (The sole exception is that we do parse analysis for ALTER COLUMN TYPE subcommands during phase 1, so that their USING expressions can be parsed against the table's original state, which is what we need. Arguably, these bugs stem from falsely concluding that because ALTER COLUMN TYPE must do early parse analysis, every other command subtype can too.) This means that ALTER TABLE itself must deal with execution of any non-ALTER-TABLE derived statements that are generated by parse analysis. Add a suitable entry point to utility.c to accept those recursive calls, and create a struct to pass through the information needed by the recursive call, rather than making the argument lists of AlterTable() and friends even longer. Getting this to work correctly required a little bit of fiddling with the subcommand pass structure, in particular breaking up AT_PASS_ADD_CONSTR into multiple passes. But otherwise it's mostly a pretty straightforward application of the above ideas. Fixing the residual issues for identity columns requires refactoring of where the dependency link from an identity column to its sequence gets set up. So that seems like suitable material for a separate patch, especially since this one is pretty big already. Discussion: https://postgr.es/m/10365.1558909428@sss.pgh.pa.us
2020-01-16 00:49:24 +01:00
cxt.blist = lappend(cxt.blist, seqstmt);
}
/*
Restructure ALTER TABLE execution to fix assorted bugs. We've had numerous bug reports about how (1) IF NOT EXISTS clauses in ALTER TABLE don't behave as-expected, and (2) combining certain actions into one ALTER TABLE doesn't work, though executing the same actions as separate statements does. This patch cleans up all of the cases so far reported from the field, though there are still some oddities associated with identity columns. The core problem behind all of these bugs is that we do parse analysis of ALTER TABLE subcommands too soon, before starting execution of the statement. The root of the bugs in group (1) is that parse analysis schedules derived commands (such as a CREATE SEQUENCE for a serial column) before it's known whether the IF NOT EXISTS clause should cause a subcommand to be skipped. The root of the bugs in group (2) is that earlier subcommands may change the catalog state that later subcommands need to be parsed against. Hence, postpone parse analysis of ALTER TABLE's subcommands, and do that one subcommand at a time, during "phase 2" of ALTER TABLE which is the phase that does catalog rewrites. Thus the catalog effects of earlier subcommands are already visible when we analyze later ones. (The sole exception is that we do parse analysis for ALTER COLUMN TYPE subcommands during phase 1, so that their USING expressions can be parsed against the table's original state, which is what we need. Arguably, these bugs stem from falsely concluding that because ALTER COLUMN TYPE must do early parse analysis, every other command subtype can too.) This means that ALTER TABLE itself must deal with execution of any non-ALTER-TABLE derived statements that are generated by parse analysis. Add a suitable entry point to utility.c to accept those recursive calls, and create a struct to pass through the information needed by the recursive call, rather than making the argument lists of AlterTable() and friends even longer. Getting this to work correctly required a little bit of fiddling with the subcommand pass structure, in particular breaking up AT_PASS_ADD_CONSTR into multiple passes. But otherwise it's mostly a pretty straightforward application of the above ideas. Fixing the residual issues for identity columns requires refactoring of where the dependency link from an identity column to its sequence gets set up. So that seems like suitable material for a separate patch, especially since this one is pretty big already. Discussion: https://postgr.es/m/10365.1558909428@sss.pgh.pa.us
2020-01-16 00:49:24 +01:00
* If column was not an identity column, we just let the
* ALTER TABLE command error out later. (There are cases
* this fails to cover, but we'll need to restructure
* where creation of the sequence dependency linkage
* happens before we can fix it.)
*/
cmd->def = (Node *) newdef;
newcmds = lappend(newcmds, cmd);
break;
}
Implement table partitioning. Table partitioning is like table inheritance and reuses much of the existing infrastructure, but there are some important differences. The parent is called a partitioned table and is always empty; it may not have indexes or non-inherited constraints, since those make no sense for a relation with no data of its own. The children are called partitions and contain all of the actual data. Each partition has an implicit partitioning constraint. Multiple inheritance is not allowed, and partitioning and inheritance can't be mixed. Partitions can't have extra columns and may not allow nulls unless the parent does. Tuples inserted into the parent are automatically routed to the correct partition, so tuple-routing ON INSERT triggers are not needed. Tuple routing isn't yet supported for partitions which are foreign tables, and it doesn't handle updates that cross partition boundaries. Currently, tables can be range-partitioned or list-partitioned. List partitioning is limited to a single column, but range partitioning can involve multiple columns. A partitioning "column" can be an expression. Because table partitioning is less general than table inheritance, it is hoped that it will be easier to reason about properties of partitions, and therefore that this will serve as a better foundation for a variety of possible optimizations, including query planner optimizations. The tuple routing based which this patch does based on the implicit partitioning constraints is an example of this, but it seems likely that many other useful optimizations are also possible. Amit Langote, reviewed and tested by Robert Haas, Ashutosh Bapat, Amit Kapila, Rajkumar Raghuwanshi, Corey Huinker, Jaime Casanova, Rushabh Lathia, Erik Rijkers, among others. Minor revisions by me.
2016-12-07 19:17:43 +01:00
case AT_AttachPartition:
case AT_DetachPartition:
Implement table partitioning. Table partitioning is like table inheritance and reuses much of the existing infrastructure, but there are some important differences. The parent is called a partitioned table and is always empty; it may not have indexes or non-inherited constraints, since those make no sense for a relation with no data of its own. The children are called partitions and contain all of the actual data. Each partition has an implicit partitioning constraint. Multiple inheritance is not allowed, and partitioning and inheritance can't be mixed. Partitions can't have extra columns and may not allow nulls unless the parent does. Tuples inserted into the parent are automatically routed to the correct partition, so tuple-routing ON INSERT triggers are not needed. Tuple routing isn't yet supported for partitions which are foreign tables, and it doesn't handle updates that cross partition boundaries. Currently, tables can be range-partitioned or list-partitioned. List partitioning is limited to a single column, but range partitioning can involve multiple columns. A partitioning "column" can be an expression. Because table partitioning is less general than table inheritance, it is hoped that it will be easier to reason about properties of partitions, and therefore that this will serve as a better foundation for a variety of possible optimizations, including query planner optimizations. The tuple routing based which this patch does based on the implicit partitioning constraints is an example of this, but it seems likely that many other useful optimizations are also possible. Amit Langote, reviewed and tested by Robert Haas, Ashutosh Bapat, Amit Kapila, Rajkumar Raghuwanshi, Corey Huinker, Jaime Casanova, Rushabh Lathia, Erik Rijkers, among others. Minor revisions by me.
2016-12-07 19:17:43 +01:00
{
PartitionCmd *partcmd = (PartitionCmd *) cmd->def;
transformPartitionCmd(&cxt, partcmd);
/* assign transformed value of the partition bound */
Implement table partitioning. Table partitioning is like table inheritance and reuses much of the existing infrastructure, but there are some important differences. The parent is called a partitioned table and is always empty; it may not have indexes or non-inherited constraints, since those make no sense for a relation with no data of its own. The children are called partitions and contain all of the actual data. Each partition has an implicit partitioning constraint. Multiple inheritance is not allowed, and partitioning and inheritance can't be mixed. Partitions can't have extra columns and may not allow nulls unless the parent does. Tuples inserted into the parent are automatically routed to the correct partition, so tuple-routing ON INSERT triggers are not needed. Tuple routing isn't yet supported for partitions which are foreign tables, and it doesn't handle updates that cross partition boundaries. Currently, tables can be range-partitioned or list-partitioned. List partitioning is limited to a single column, but range partitioning can involve multiple columns. A partitioning "column" can be an expression. Because table partitioning is less general than table inheritance, it is hoped that it will be easier to reason about properties of partitions, and therefore that this will serve as a better foundation for a variety of possible optimizations, including query planner optimizations. The tuple routing based which this patch does based on the implicit partitioning constraints is an example of this, but it seems likely that many other useful optimizations are also possible. Amit Langote, reviewed and tested by Robert Haas, Ashutosh Bapat, Amit Kapila, Rajkumar Raghuwanshi, Corey Huinker, Jaime Casanova, Rushabh Lathia, Erik Rijkers, among others. Minor revisions by me.
2016-12-07 19:17:43 +01:00
partcmd->bound = cxt.partbound;
}
newcmds = lappend(newcmds, cmd);
break;
default:
Restructure ALTER TABLE execution to fix assorted bugs. We've had numerous bug reports about how (1) IF NOT EXISTS clauses in ALTER TABLE don't behave as-expected, and (2) combining certain actions into one ALTER TABLE doesn't work, though executing the same actions as separate statements does. This patch cleans up all of the cases so far reported from the field, though there are still some oddities associated with identity columns. The core problem behind all of these bugs is that we do parse analysis of ALTER TABLE subcommands too soon, before starting execution of the statement. The root of the bugs in group (1) is that parse analysis schedules derived commands (such as a CREATE SEQUENCE for a serial column) before it's known whether the IF NOT EXISTS clause should cause a subcommand to be skipped. The root of the bugs in group (2) is that earlier subcommands may change the catalog state that later subcommands need to be parsed against. Hence, postpone parse analysis of ALTER TABLE's subcommands, and do that one subcommand at a time, during "phase 2" of ALTER TABLE which is the phase that does catalog rewrites. Thus the catalog effects of earlier subcommands are already visible when we analyze later ones. (The sole exception is that we do parse analysis for ALTER COLUMN TYPE subcommands during phase 1, so that their USING expressions can be parsed against the table's original state, which is what we need. Arguably, these bugs stem from falsely concluding that because ALTER COLUMN TYPE must do early parse analysis, every other command subtype can too.) This means that ALTER TABLE itself must deal with execution of any non-ALTER-TABLE derived statements that are generated by parse analysis. Add a suitable entry point to utility.c to accept those recursive calls, and create a struct to pass through the information needed by the recursive call, rather than making the argument lists of AlterTable() and friends even longer. Getting this to work correctly required a little bit of fiddling with the subcommand pass structure, in particular breaking up AT_PASS_ADD_CONSTR into multiple passes. But otherwise it's mostly a pretty straightforward application of the above ideas. Fixing the residual issues for identity columns requires refactoring of where the dependency link from an identity column to its sequence gets set up. So that seems like suitable material for a separate patch, especially since this one is pretty big already. Discussion: https://postgr.es/m/10365.1558909428@sss.pgh.pa.us
2020-01-16 00:49:24 +01:00
/*
* Currently, we shouldn't actually get here for subcommand
* types that don't require transformation; but if we do, just
* emit them unchanged.
*/
newcmds = lappend(newcmds, cmd);
break;
}
}
/*
Avoid order-of-execution problems with ALTER TABLE ADD PRIMARY KEY. Up to now, DefineIndex() was responsible for adding attnotnull constraints to the columns of a primary key, in any case where it hadn't been convenient for transformIndexConstraint() to mark those columns as is_not_null. It (or rather its minion index_check_primary_key) did this by executing an ALTER TABLE SET NOT NULL command for the target table. The trouble with this solution is that if we're creating the index due to ALTER TABLE ADD PRIMARY KEY, and the outer ALTER TABLE has additional sub-commands, the inner ALTER TABLE's operations executed at the wrong time with respect to the outer ALTER TABLE's operations. In particular, the inner ALTER would perform a validation scan at a point where the table's storage might be inconsistent with its catalog entries. (This is on the hairy edge of being a security problem, but AFAICS it isn't one because the inner scan would only be interested in the tuples' null bitmaps.) This can result in unexpected failures, such as the one seen in bug #15580 from Allison Kaptur. To fix, let's remove the attempt to do SET NOT NULL from DefineIndex(), reducing index_check_primary_key's role to verifying that the columns are already not null. (It shouldn't ever see such a case, but it seems wise to keep the check for safety.) Instead, make transformIndexConstraint() generate ALTER TABLE SET NOT NULL subcommands to be executed ahead of the ADD PRIMARY KEY operation in every case where it can't force the column to be created already-not-null. This requires only minor surgery in parse_utilcmd.c, and it makes for a much more satisfying spec for transformIndexConstraint(): it's no longer having to take it on faith that someone else will handle addition of NOT NULL constraints. To make that work, we have to move the execution of AT_SetNotNull into an ALTER pass that executes ahead of AT_PASS_ADD_INDEX. I moved it to AT_PASS_COL_ATTRS, and put that after AT_PASS_ADD_COL to avoid failure when the column is being added in the same command. This incidentally fixes a bug in the only previous usage of AT_PASS_COL_ATTRS, for AT_SetIdentity: it didn't work either for a newly-added column. Playing around with this exposed a separate bug in ALTER TABLE ONLY ... ADD PRIMARY KEY for partitioned tables. The intent of the ONLY modifier in that context is to prevent doing anything that would require holding lock for a long time --- but the implied SET NOT NULL would recurse to the child partitions, and do an expensive validation scan for any child where the column(s) were not already NOT NULL. To fix that, invent a new ALTER subcommand AT_CheckNotNull that just insists that a child column be already NOT NULL, and apply that, not AT_SetNotNull, when recursing to children in this scenario. This results in a slightly laxer definition of ALTER TABLE ONLY ... SET NOT NULL for partitioned tables, too: that command will now work as long as all children are already NOT NULL, whereas before it just threw up its hands if there were any partitions. In passing, clean up the API of generateClonedIndexStmt(): remove a useless argument, ensure that the output argument is not left undefined, update the header comment. A small side effect of this change is that no-such-column errors in ALTER TABLE ADD PRIMARY KEY now produce a different message that includes the table name, because they are now detected by the SET NOT NULL step which has historically worded its error that way. That seems fine to me, so I didn't make any effort to avoid the wording change. The basic bug #15580 is of very long standing, and these other bugs aren't new in v12 either. However, this is a pretty significant change in the way ALTER TABLE ADD PRIMARY KEY works. On balance it seems best not to back-patch, at least not till we get some more confidence that this patch has no new bugs. Patch by me, but thanks to Jie Zhang for a preliminary version. Discussion: https://postgr.es/m/15580-d1a6de5a3d65da51@postgresql.org Discussion: https://postgr.es/m/1396E95157071C4EBBA51892C5368521017F2E6E63@G08CNEXMBPEKD02.g08.fujitsu.local
2019-04-23 18:25:27 +02:00
* Transfer anything we already have in cxt.alist into save_alist, to keep
* it separate from the output of transformIndexConstraints.
*/
save_alist = cxt.alist;
cxt.alist = NIL;
/* Postprocess constraints */
transformIndexConstraints(&cxt);
transformFKConstraints(&cxt, skipValidation, true);
transformCheckConstraints(&cxt, false);
/*
* Push any index-creation commands into the ALTER, so that they can be
* scheduled nicely by tablecmds.c. Note that tablecmds.c assumes that
* the IndexStmt attached to an AT_AddIndex or AT_AddIndexConstraint
* subcommand has already been through transformIndexStmt.
*/
foreach(l, cxt.alist)
{
Avoid order-of-execution problems with ALTER TABLE ADD PRIMARY KEY. Up to now, DefineIndex() was responsible for adding attnotnull constraints to the columns of a primary key, in any case where it hadn't been convenient for transformIndexConstraint() to mark those columns as is_not_null. It (or rather its minion index_check_primary_key) did this by executing an ALTER TABLE SET NOT NULL command for the target table. The trouble with this solution is that if we're creating the index due to ALTER TABLE ADD PRIMARY KEY, and the outer ALTER TABLE has additional sub-commands, the inner ALTER TABLE's operations executed at the wrong time with respect to the outer ALTER TABLE's operations. In particular, the inner ALTER would perform a validation scan at a point where the table's storage might be inconsistent with its catalog entries. (This is on the hairy edge of being a security problem, but AFAICS it isn't one because the inner scan would only be interested in the tuples' null bitmaps.) This can result in unexpected failures, such as the one seen in bug #15580 from Allison Kaptur. To fix, let's remove the attempt to do SET NOT NULL from DefineIndex(), reducing index_check_primary_key's role to verifying that the columns are already not null. (It shouldn't ever see such a case, but it seems wise to keep the check for safety.) Instead, make transformIndexConstraint() generate ALTER TABLE SET NOT NULL subcommands to be executed ahead of the ADD PRIMARY KEY operation in every case where it can't force the column to be created already-not-null. This requires only minor surgery in parse_utilcmd.c, and it makes for a much more satisfying spec for transformIndexConstraint(): it's no longer having to take it on faith that someone else will handle addition of NOT NULL constraints. To make that work, we have to move the execution of AT_SetNotNull into an ALTER pass that executes ahead of AT_PASS_ADD_INDEX. I moved it to AT_PASS_COL_ATTRS, and put that after AT_PASS_ADD_COL to avoid failure when the column is being added in the same command. This incidentally fixes a bug in the only previous usage of AT_PASS_COL_ATTRS, for AT_SetIdentity: it didn't work either for a newly-added column. Playing around with this exposed a separate bug in ALTER TABLE ONLY ... ADD PRIMARY KEY for partitioned tables. The intent of the ONLY modifier in that context is to prevent doing anything that would require holding lock for a long time --- but the implied SET NOT NULL would recurse to the child partitions, and do an expensive validation scan for any child where the column(s) were not already NOT NULL. To fix that, invent a new ALTER subcommand AT_CheckNotNull that just insists that a child column be already NOT NULL, and apply that, not AT_SetNotNull, when recursing to children in this scenario. This results in a slightly laxer definition of ALTER TABLE ONLY ... SET NOT NULL for partitioned tables, too: that command will now work as long as all children are already NOT NULL, whereas before it just threw up its hands if there were any partitions. In passing, clean up the API of generateClonedIndexStmt(): remove a useless argument, ensure that the output argument is not left undefined, update the header comment. A small side effect of this change is that no-such-column errors in ALTER TABLE ADD PRIMARY KEY now produce a different message that includes the table name, because they are now detected by the SET NOT NULL step which has historically worded its error that way. That seems fine to me, so I didn't make any effort to avoid the wording change. The basic bug #15580 is of very long standing, and these other bugs aren't new in v12 either. However, this is a pretty significant change in the way ALTER TABLE ADD PRIMARY KEY works. On balance it seems best not to back-patch, at least not till we get some more confidence that this patch has no new bugs. Patch by me, but thanks to Jie Zhang for a preliminary version. Discussion: https://postgr.es/m/15580-d1a6de5a3d65da51@postgresql.org Discussion: https://postgr.es/m/1396E95157071C4EBBA51892C5368521017F2E6E63@G08CNEXMBPEKD02.g08.fujitsu.local
2019-04-23 18:25:27 +02:00
Node *istmt = (Node *) lfirst(l);
Avoid order-of-execution problems with ALTER TABLE ADD PRIMARY KEY. Up to now, DefineIndex() was responsible for adding attnotnull constraints to the columns of a primary key, in any case where it hadn't been convenient for transformIndexConstraint() to mark those columns as is_not_null. It (or rather its minion index_check_primary_key) did this by executing an ALTER TABLE SET NOT NULL command for the target table. The trouble with this solution is that if we're creating the index due to ALTER TABLE ADD PRIMARY KEY, and the outer ALTER TABLE has additional sub-commands, the inner ALTER TABLE's operations executed at the wrong time with respect to the outer ALTER TABLE's operations. In particular, the inner ALTER would perform a validation scan at a point where the table's storage might be inconsistent with its catalog entries. (This is on the hairy edge of being a security problem, but AFAICS it isn't one because the inner scan would only be interested in the tuples' null bitmaps.) This can result in unexpected failures, such as the one seen in bug #15580 from Allison Kaptur. To fix, let's remove the attempt to do SET NOT NULL from DefineIndex(), reducing index_check_primary_key's role to verifying that the columns are already not null. (It shouldn't ever see such a case, but it seems wise to keep the check for safety.) Instead, make transformIndexConstraint() generate ALTER TABLE SET NOT NULL subcommands to be executed ahead of the ADD PRIMARY KEY operation in every case where it can't force the column to be created already-not-null. This requires only minor surgery in parse_utilcmd.c, and it makes for a much more satisfying spec for transformIndexConstraint(): it's no longer having to take it on faith that someone else will handle addition of NOT NULL constraints. To make that work, we have to move the execution of AT_SetNotNull into an ALTER pass that executes ahead of AT_PASS_ADD_INDEX. I moved it to AT_PASS_COL_ATTRS, and put that after AT_PASS_ADD_COL to avoid failure when the column is being added in the same command. This incidentally fixes a bug in the only previous usage of AT_PASS_COL_ATTRS, for AT_SetIdentity: it didn't work either for a newly-added column. Playing around with this exposed a separate bug in ALTER TABLE ONLY ... ADD PRIMARY KEY for partitioned tables. The intent of the ONLY modifier in that context is to prevent doing anything that would require holding lock for a long time --- but the implied SET NOT NULL would recurse to the child partitions, and do an expensive validation scan for any child where the column(s) were not already NOT NULL. To fix that, invent a new ALTER subcommand AT_CheckNotNull that just insists that a child column be already NOT NULL, and apply that, not AT_SetNotNull, when recursing to children in this scenario. This results in a slightly laxer definition of ALTER TABLE ONLY ... SET NOT NULL for partitioned tables, too: that command will now work as long as all children are already NOT NULL, whereas before it just threw up its hands if there were any partitions. In passing, clean up the API of generateClonedIndexStmt(): remove a useless argument, ensure that the output argument is not left undefined, update the header comment. A small side effect of this change is that no-such-column errors in ALTER TABLE ADD PRIMARY KEY now produce a different message that includes the table name, because they are now detected by the SET NOT NULL step which has historically worded its error that way. That seems fine to me, so I didn't make any effort to avoid the wording change. The basic bug #15580 is of very long standing, and these other bugs aren't new in v12 either. However, this is a pretty significant change in the way ALTER TABLE ADD PRIMARY KEY works. On balance it seems best not to back-patch, at least not till we get some more confidence that this patch has no new bugs. Patch by me, but thanks to Jie Zhang for a preliminary version. Discussion: https://postgr.es/m/15580-d1a6de5a3d65da51@postgresql.org Discussion: https://postgr.es/m/1396E95157071C4EBBA51892C5368521017F2E6E63@G08CNEXMBPEKD02.g08.fujitsu.local
2019-04-23 18:25:27 +02:00
/*
* We assume here that cxt.alist contains only IndexStmts and possibly
* ALTER TABLE SET NOT NULL statements generated from primary key
* constraints. We absorb the subcommands of the latter directly.
Avoid order-of-execution problems with ALTER TABLE ADD PRIMARY KEY. Up to now, DefineIndex() was responsible for adding attnotnull constraints to the columns of a primary key, in any case where it hadn't been convenient for transformIndexConstraint() to mark those columns as is_not_null. It (or rather its minion index_check_primary_key) did this by executing an ALTER TABLE SET NOT NULL command for the target table. The trouble with this solution is that if we're creating the index due to ALTER TABLE ADD PRIMARY KEY, and the outer ALTER TABLE has additional sub-commands, the inner ALTER TABLE's operations executed at the wrong time with respect to the outer ALTER TABLE's operations. In particular, the inner ALTER would perform a validation scan at a point where the table's storage might be inconsistent with its catalog entries. (This is on the hairy edge of being a security problem, but AFAICS it isn't one because the inner scan would only be interested in the tuples' null bitmaps.) This can result in unexpected failures, such as the one seen in bug #15580 from Allison Kaptur. To fix, let's remove the attempt to do SET NOT NULL from DefineIndex(), reducing index_check_primary_key's role to verifying that the columns are already not null. (It shouldn't ever see such a case, but it seems wise to keep the check for safety.) Instead, make transformIndexConstraint() generate ALTER TABLE SET NOT NULL subcommands to be executed ahead of the ADD PRIMARY KEY operation in every case where it can't force the column to be created already-not-null. This requires only minor surgery in parse_utilcmd.c, and it makes for a much more satisfying spec for transformIndexConstraint(): it's no longer having to take it on faith that someone else will handle addition of NOT NULL constraints. To make that work, we have to move the execution of AT_SetNotNull into an ALTER pass that executes ahead of AT_PASS_ADD_INDEX. I moved it to AT_PASS_COL_ATTRS, and put that after AT_PASS_ADD_COL to avoid failure when the column is being added in the same command. This incidentally fixes a bug in the only previous usage of AT_PASS_COL_ATTRS, for AT_SetIdentity: it didn't work either for a newly-added column. Playing around with this exposed a separate bug in ALTER TABLE ONLY ... ADD PRIMARY KEY for partitioned tables. The intent of the ONLY modifier in that context is to prevent doing anything that would require holding lock for a long time --- but the implied SET NOT NULL would recurse to the child partitions, and do an expensive validation scan for any child where the column(s) were not already NOT NULL. To fix that, invent a new ALTER subcommand AT_CheckNotNull that just insists that a child column be already NOT NULL, and apply that, not AT_SetNotNull, when recursing to children in this scenario. This results in a slightly laxer definition of ALTER TABLE ONLY ... SET NOT NULL for partitioned tables, too: that command will now work as long as all children are already NOT NULL, whereas before it just threw up its hands if there were any partitions. In passing, clean up the API of generateClonedIndexStmt(): remove a useless argument, ensure that the output argument is not left undefined, update the header comment. A small side effect of this change is that no-such-column errors in ALTER TABLE ADD PRIMARY KEY now produce a different message that includes the table name, because they are now detected by the SET NOT NULL step which has historically worded its error that way. That seems fine to me, so I didn't make any effort to avoid the wording change. The basic bug #15580 is of very long standing, and these other bugs aren't new in v12 either. However, this is a pretty significant change in the way ALTER TABLE ADD PRIMARY KEY works. On balance it seems best not to back-patch, at least not till we get some more confidence that this patch has no new bugs. Patch by me, but thanks to Jie Zhang for a preliminary version. Discussion: https://postgr.es/m/15580-d1a6de5a3d65da51@postgresql.org Discussion: https://postgr.es/m/1396E95157071C4EBBA51892C5368521017F2E6E63@G08CNEXMBPEKD02.g08.fujitsu.local
2019-04-23 18:25:27 +02:00
*/
if (IsA(istmt, IndexStmt))
{
IndexStmt *idxstmt = (IndexStmt *) istmt;
idxstmt = transformIndexStmt(relid, idxstmt, queryString);
newcmd = makeNode(AlterTableCmd);
newcmd->subtype = OidIsValid(idxstmt->indexOid) ? AT_AddIndexConstraint : AT_AddIndex;
newcmd->def = (Node *) idxstmt;
newcmds = lappend(newcmds, newcmd);
}
else if (IsA(istmt, AlterTableStmt))
{
AlterTableStmt *alterstmt = (AlterTableStmt *) istmt;
newcmds = list_concat(newcmds, alterstmt->cmds);
}
else
elog(ERROR, "unexpected stmt type %d", (int) nodeTag(istmt));
}
cxt.alist = NIL;
/* Append any CHECK or FK constraints to the commands list */
foreach(l, cxt.ckconstraints)
{
newcmd = makeNode(AlterTableCmd);
newcmd->subtype = AT_AddConstraint;
newcmd->def = (Node *) lfirst(l);
newcmds = lappend(newcmds, newcmd);
}
foreach(l, cxt.fkconstraints)
{
newcmd = makeNode(AlterTableCmd);
newcmd->subtype = AT_AddConstraint;
newcmd->def = (Node *) lfirst(l);
newcmds = lappend(newcmds, newcmd);
}
/* Append extended statistics objects */
transformExtendedStatistics(&cxt);
/* Close rel */
relation_close(rel, NoLock);
/*
* Output results.
*/
stmt->cmds = newcmds;
Restructure ALTER TABLE execution to fix assorted bugs. We've had numerous bug reports about how (1) IF NOT EXISTS clauses in ALTER TABLE don't behave as-expected, and (2) combining certain actions into one ALTER TABLE doesn't work, though executing the same actions as separate statements does. This patch cleans up all of the cases so far reported from the field, though there are still some oddities associated with identity columns. The core problem behind all of these bugs is that we do parse analysis of ALTER TABLE subcommands too soon, before starting execution of the statement. The root of the bugs in group (1) is that parse analysis schedules derived commands (such as a CREATE SEQUENCE for a serial column) before it's known whether the IF NOT EXISTS clause should cause a subcommand to be skipped. The root of the bugs in group (2) is that earlier subcommands may change the catalog state that later subcommands need to be parsed against. Hence, postpone parse analysis of ALTER TABLE's subcommands, and do that one subcommand at a time, during "phase 2" of ALTER TABLE which is the phase that does catalog rewrites. Thus the catalog effects of earlier subcommands are already visible when we analyze later ones. (The sole exception is that we do parse analysis for ALTER COLUMN TYPE subcommands during phase 1, so that their USING expressions can be parsed against the table's original state, which is what we need. Arguably, these bugs stem from falsely concluding that because ALTER COLUMN TYPE must do early parse analysis, every other command subtype can too.) This means that ALTER TABLE itself must deal with execution of any non-ALTER-TABLE derived statements that are generated by parse analysis. Add a suitable entry point to utility.c to accept those recursive calls, and create a struct to pass through the information needed by the recursive call, rather than making the argument lists of AlterTable() and friends even longer. Getting this to work correctly required a little bit of fiddling with the subcommand pass structure, in particular breaking up AT_PASS_ADD_CONSTR into multiple passes. But otherwise it's mostly a pretty straightforward application of the above ideas. Fixing the residual issues for identity columns requires refactoring of where the dependency link from an identity column to its sequence gets set up. So that seems like suitable material for a separate patch, especially since this one is pretty big already. Discussion: https://postgr.es/m/10365.1558909428@sss.pgh.pa.us
2020-01-16 00:49:24 +01:00
*beforeStmts = cxt.blist;
*afterStmts = list_concat(cxt.alist, save_alist);
Restructure ALTER TABLE execution to fix assorted bugs. We've had numerous bug reports about how (1) IF NOT EXISTS clauses in ALTER TABLE don't behave as-expected, and (2) combining certain actions into one ALTER TABLE doesn't work, though executing the same actions as separate statements does. This patch cleans up all of the cases so far reported from the field, though there are still some oddities associated with identity columns. The core problem behind all of these bugs is that we do parse analysis of ALTER TABLE subcommands too soon, before starting execution of the statement. The root of the bugs in group (1) is that parse analysis schedules derived commands (such as a CREATE SEQUENCE for a serial column) before it's known whether the IF NOT EXISTS clause should cause a subcommand to be skipped. The root of the bugs in group (2) is that earlier subcommands may change the catalog state that later subcommands need to be parsed against. Hence, postpone parse analysis of ALTER TABLE's subcommands, and do that one subcommand at a time, during "phase 2" of ALTER TABLE which is the phase that does catalog rewrites. Thus the catalog effects of earlier subcommands are already visible when we analyze later ones. (The sole exception is that we do parse analysis for ALTER COLUMN TYPE subcommands during phase 1, so that their USING expressions can be parsed against the table's original state, which is what we need. Arguably, these bugs stem from falsely concluding that because ALTER COLUMN TYPE must do early parse analysis, every other command subtype can too.) This means that ALTER TABLE itself must deal with execution of any non-ALTER-TABLE derived statements that are generated by parse analysis. Add a suitable entry point to utility.c to accept those recursive calls, and create a struct to pass through the information needed by the recursive call, rather than making the argument lists of AlterTable() and friends even longer. Getting this to work correctly required a little bit of fiddling with the subcommand pass structure, in particular breaking up AT_PASS_ADD_CONSTR into multiple passes. But otherwise it's mostly a pretty straightforward application of the above ideas. Fixing the residual issues for identity columns requires refactoring of where the dependency link from an identity column to its sequence gets set up. So that seems like suitable material for a separate patch, especially since this one is pretty big already. Discussion: https://postgr.es/m/10365.1558909428@sss.pgh.pa.us
2020-01-16 00:49:24 +01:00
return stmt;
}
/*
* Preprocess a list of column constraint clauses
* to attach constraint attributes to their primary constraint nodes
* and detect inconsistent/misplaced constraint attributes.
*
* NOTE: currently, attributes are only supported for FOREIGN KEY, UNIQUE,
* EXCLUSION, and PRIMARY KEY constraints, but someday they ought to be
* supported for other constraint types.
*/
static void
transformConstraintAttrs(CreateStmtContext *cxt, List *constraintList)
{
Constraint *lastprimarycon = NULL;
bool saw_deferrability = false;
bool saw_initially = false;
ListCell *clist;
#define SUPPORTS_ATTRS(node) \
((node) != NULL && \
((node)->contype == CONSTR_PRIMARY || \
(node)->contype == CONSTR_UNIQUE || \
(node)->contype == CONSTR_EXCLUSION || \
(node)->contype == CONSTR_FOREIGN))
foreach(clist, constraintList)
{
Constraint *con = (Constraint *) lfirst(clist);
if (!IsA(con, Constraint))
elog(ERROR, "unrecognized node type: %d",
(int) nodeTag(con));
switch (con->contype)
{
case CONSTR_ATTR_DEFERRABLE:
if (!SUPPORTS_ATTRS(lastprimarycon))
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("misplaced DEFERRABLE clause"),
parser_errposition(cxt->pstate, con->location)));
if (saw_deferrability)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("multiple DEFERRABLE/NOT DEFERRABLE clauses not allowed"),
parser_errposition(cxt->pstate, con->location)));
saw_deferrability = true;
lastprimarycon->deferrable = true;
break;
case CONSTR_ATTR_NOT_DEFERRABLE:
if (!SUPPORTS_ATTRS(lastprimarycon))
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("misplaced NOT DEFERRABLE clause"),
parser_errposition(cxt->pstate, con->location)));
if (saw_deferrability)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("multiple DEFERRABLE/NOT DEFERRABLE clauses not allowed"),
parser_errposition(cxt->pstate, con->location)));
saw_deferrability = true;
lastprimarycon->deferrable = false;
if (saw_initially &&
lastprimarycon->initdeferred)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("constraint declared INITIALLY DEFERRED must be DEFERRABLE"),
parser_errposition(cxt->pstate, con->location)));
break;
case CONSTR_ATTR_DEFERRED:
if (!SUPPORTS_ATTRS(lastprimarycon))
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("misplaced INITIALLY DEFERRED clause"),
parser_errposition(cxt->pstate, con->location)));
if (saw_initially)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("multiple INITIALLY IMMEDIATE/DEFERRED clauses not allowed"),
parser_errposition(cxt->pstate, con->location)));
saw_initially = true;
lastprimarycon->initdeferred = true;
/*
* If only INITIALLY DEFERRED appears, assume DEFERRABLE
*/
if (!saw_deferrability)
lastprimarycon->deferrable = true;
else if (!lastprimarycon->deferrable)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("constraint declared INITIALLY DEFERRED must be DEFERRABLE"),
parser_errposition(cxt->pstate, con->location)));
break;
case CONSTR_ATTR_IMMEDIATE:
if (!SUPPORTS_ATTRS(lastprimarycon))
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("misplaced INITIALLY IMMEDIATE clause"),
parser_errposition(cxt->pstate, con->location)));
if (saw_initially)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("multiple INITIALLY IMMEDIATE/DEFERRED clauses not allowed"),
parser_errposition(cxt->pstate, con->location)));
saw_initially = true;
lastprimarycon->initdeferred = false;
break;
default:
/* Otherwise it's not an attribute */
lastprimarycon = con;
/* reset flags for new primary node */
saw_deferrability = false;
saw_initially = false;
break;
}
}
}
/*
* Special handling of type definition for a column
*/
static void
transformColumnType(CreateStmtContext *cxt, ColumnDef *column)
{
/*
Remove collation information from TypeName, where it does not belong. The initial collations patch treated a COLLATE spec as part of a TypeName, following what can only be described as brain fade on the part of the SQL committee. It's a lot more reasonable to treat COLLATE as a syntactically separate object, so that it can be added in only the productions where it actually belongs, rather than needing to reject it in a boatload of places where it doesn't belong (something the original patch mostly failed to do). In addition this change lets us meet the spec's requirement to allow COLLATE anywhere in the clauses of a ColumnDef, and it avoids unfriendly behavior for constructs such as "foo::type COLLATE collation". To do this, pull collation information out of TypeName and put it in ColumnDef instead, thus reverting most of the collation-related changes in parse_type.c's API. I made one additional structural change, which was to use a ColumnDef as an intermediate node in AT_AlterColumnType AlterTableCmd nodes. This provides enough room to get rid of the "transform" wart in AlterTableCmd too, since the ColumnDef can carry the USING expression easily enough. Also fix some other minor bugs that have crept in in the same areas, like failure to copy recently-added fields of ColumnDef in copyfuncs.c. While at it, document the formerly secret ability to specify a collation in ALTER TABLE ALTER COLUMN TYPE, ALTER TYPE ADD ATTRIBUTE, and ALTER TYPE ALTER ATTRIBUTE TYPE; and correct some misstatements about what the default collation selection will be when COLLATE is omitted. BTW, the three-parameter form of format_type() should go away too, since it just contributes to the confusion in this area; but I'll do that in a separate patch.
2011-03-10 04:38:52 +01:00
* All we really need to do here is verify that the type is valid,
* including any collation spec that might be present.
*/
Remove collation information from TypeName, where it does not belong. The initial collations patch treated a COLLATE spec as part of a TypeName, following what can only be described as brain fade on the part of the SQL committee. It's a lot more reasonable to treat COLLATE as a syntactically separate object, so that it can be added in only the productions where it actually belongs, rather than needing to reject it in a boatload of places where it doesn't belong (something the original patch mostly failed to do). In addition this change lets us meet the spec's requirement to allow COLLATE anywhere in the clauses of a ColumnDef, and it avoids unfriendly behavior for constructs such as "foo::type COLLATE collation". To do this, pull collation information out of TypeName and put it in ColumnDef instead, thus reverting most of the collation-related changes in parse_type.c's API. I made one additional structural change, which was to use a ColumnDef as an intermediate node in AT_AlterColumnType AlterTableCmd nodes. This provides enough room to get rid of the "transform" wart in AlterTableCmd too, since the ColumnDef can carry the USING expression easily enough. Also fix some other minor bugs that have crept in in the same areas, like failure to copy recently-added fields of ColumnDef in copyfuncs.c. While at it, document the formerly secret ability to specify a collation in ALTER TABLE ALTER COLUMN TYPE, ALTER TYPE ADD ATTRIBUTE, and ALTER TYPE ALTER ATTRIBUTE TYPE; and correct some misstatements about what the default collation selection will be when COLLATE is omitted. BTW, the three-parameter form of format_type() should go away too, since it just contributes to the confusion in this area; but I'll do that in a separate patch.
2011-03-10 04:38:52 +01:00
Type ctype = typenameType(cxt->pstate, column->typeName, NULL);
if (column->collClause)
{
Form_pg_type typtup = (Form_pg_type) GETSTRUCT(ctype);
LookupCollation(cxt->pstate,
column->collClause->collname,
Remove collation information from TypeName, where it does not belong. The initial collations patch treated a COLLATE spec as part of a TypeName, following what can only be described as brain fade on the part of the SQL committee. It's a lot more reasonable to treat COLLATE as a syntactically separate object, so that it can be added in only the productions where it actually belongs, rather than needing to reject it in a boatload of places where it doesn't belong (something the original patch mostly failed to do). In addition this change lets us meet the spec's requirement to allow COLLATE anywhere in the clauses of a ColumnDef, and it avoids unfriendly behavior for constructs such as "foo::type COLLATE collation". To do this, pull collation information out of TypeName and put it in ColumnDef instead, thus reverting most of the collation-related changes in parse_type.c's API. I made one additional structural change, which was to use a ColumnDef as an intermediate node in AT_AlterColumnType AlterTableCmd nodes. This provides enough room to get rid of the "transform" wart in AlterTableCmd too, since the ColumnDef can carry the USING expression easily enough. Also fix some other minor bugs that have crept in in the same areas, like failure to copy recently-added fields of ColumnDef in copyfuncs.c. While at it, document the formerly secret ability to specify a collation in ALTER TABLE ALTER COLUMN TYPE, ALTER TYPE ADD ATTRIBUTE, and ALTER TYPE ALTER ATTRIBUTE TYPE; and correct some misstatements about what the default collation selection will be when COLLATE is omitted. BTW, the three-parameter form of format_type() should go away too, since it just contributes to the confusion in this area; but I'll do that in a separate patch.
2011-03-10 04:38:52 +01:00
column->collClause->location);
/* Complain if COLLATE is applied to an uncollatable type */
if (!OidIsValid(typtup->typcollation))
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
errmsg("collations are not supported by type %s",
Remove WITH OIDS support, change oid catalog column visibility. Previously tables declared WITH OIDS, including a significant fraction of the catalog tables, stored the oid column not as a normal column, but as part of the tuple header. This special column was not shown by default, which was somewhat odd, as it's often (consider e.g. pg_class.oid) one of the more important parts of a row. Neither pg_dump nor COPY included the contents of the oid column by default. The fact that the oid column was not an ordinary column necessitated a significant amount of special case code to support oid columns. That already was painful for the existing, but upcoming work aiming to make table storage pluggable, would have required expanding and duplicating that "specialness" significantly. WITH OIDS has been deprecated since 2005 (commit ff02d0a05280e0). Remove it. Removing includes: - CREATE TABLE and ALTER TABLE syntax for declaring the table to be WITH OIDS has been removed (WITH (oids[ = true]) will error out) - pg_dump does not support dumping tables declared WITH OIDS and will issue a warning when dumping one (and ignore the oid column). - restoring an pg_dump archive with pg_restore will warn when restoring a table with oid contents (and ignore the oid column) - COPY will refuse to load binary dump that includes oids. - pg_upgrade will error out when encountering tables declared WITH OIDS, they have to be altered to remove the oid column first. - Functionality to access the oid of the last inserted row (like plpgsql's RESULT_OID, spi's SPI_lastoid, ...) has been removed. The syntax for declaring a table WITHOUT OIDS (or WITH (oids = false) for CREATE TABLE) is still supported. While that requires a bit of support code, it seems unnecessary to break applications / dumps that do not use oids, and are explicit about not using them. The biggest user of WITH OID columns was postgres' catalog. This commit changes all 'magic' oid columns to be columns that are normally declared and stored. To reduce unnecessary query breakage all the newly added columns are still named 'oid', even if a table's column naming scheme would indicate 'reloid' or such. This obviously requires adapting a lot code, mostly replacing oid access via HeapTupleGetOid() with access to the underlying Form_pg_*->oid column. The bootstrap process now assigns oids for all oid columns in genbki.pl that do not have an explicit value (starting at the largest oid previously used), only oids assigned later by oids will be above FirstBootstrapObjectId. As the oid column now is a normal column the special bootstrap syntax for oids has been removed. Oids are not automatically assigned during insertion anymore, all backend code explicitly assigns oids with GetNewOidWithIndex(). For the rare case that insertions into the catalog via SQL are called for the new pg_nextoid() function can be used (which only works on catalog tables). The fact that oid columns on system tables are now normal columns means that they will be included in the set of columns expanded by * (i.e. SELECT * FROM pg_class will now include the table's oid, previously it did not). It'd not technically be hard to hide oid column by default, but that'd mean confusing behavior would either have to be carried forward forever, or it'd cause breakage down the line. While it's not unlikely that further adjustments are needed, the scope/invasiveness of the patch makes it worthwhile to get merge this now. It's painful to maintain externally, too complicated to commit after the code code freeze, and a dependency of a number of other patches. Catversion bump, for obvious reasons. Author: Andres Freund, with contributions by John Naylor Discussion: https://postgr.es/m/20180930034810.ywp2c7awz7opzcfr@alap3.anarazel.de
2018-11-21 00:36:57 +01:00
format_type_be(typtup->oid)),
Remove collation information from TypeName, where it does not belong. The initial collations patch treated a COLLATE spec as part of a TypeName, following what can only be described as brain fade on the part of the SQL committee. It's a lot more reasonable to treat COLLATE as a syntactically separate object, so that it can be added in only the productions where it actually belongs, rather than needing to reject it in a boatload of places where it doesn't belong (something the original patch mostly failed to do). In addition this change lets us meet the spec's requirement to allow COLLATE anywhere in the clauses of a ColumnDef, and it avoids unfriendly behavior for constructs such as "foo::type COLLATE collation". To do this, pull collation information out of TypeName and put it in ColumnDef instead, thus reverting most of the collation-related changes in parse_type.c's API. I made one additional structural change, which was to use a ColumnDef as an intermediate node in AT_AlterColumnType AlterTableCmd nodes. This provides enough room to get rid of the "transform" wart in AlterTableCmd too, since the ColumnDef can carry the USING expression easily enough. Also fix some other minor bugs that have crept in in the same areas, like failure to copy recently-added fields of ColumnDef in copyfuncs.c. While at it, document the formerly secret ability to specify a collation in ALTER TABLE ALTER COLUMN TYPE, ALTER TYPE ADD ATTRIBUTE, and ALTER TYPE ALTER ATTRIBUTE TYPE; and correct some misstatements about what the default collation selection will be when COLLATE is omitted. BTW, the three-parameter form of format_type() should go away too, since it just contributes to the confusion in this area; but I'll do that in a separate patch.
2011-03-10 04:38:52 +01:00
parser_errposition(cxt->pstate,
column->collClause->location)));
}
ReleaseSysCache(ctype);
}
/*
Fix crashes with CREATE SCHEMA AUTHORIZATION and schema elements CREATE SCHEMA AUTHORIZATION with appended schema elements can lead to crashes when comparing the schema name of the query with the schemas used in the qualification of some clauses in the elements' queries. The origin of the problem is that the transformation routine for the elements listed in a CREATE SCHEMA query uses as new, expected, schema name the one listed in CreateSchemaStmt itself. However, depending on the query, CreateSchemaStmt.schemaname may be NULL, being computed instead from the role specification of the query given by the AUTHORIZATION clause, that could be either: - A user name string, with the new schema name being set to the same value as the role given. - Guessed from CURRENT_ROLE, SESSION_ROLE or CURRENT_ROLE, with a new schema name computed from the security context where CREATE SCHEMA is running. Regression tests are added for CREATE SCHEMA with some appended elements (some of them with schema qualifications), covering also some role specification patterns. While on it, this simplifies the context structure used during the transformation of the elements listed in a CREATE SCHEMA query by removing the fields for the role specification and the role type. They were not used, and for the role specification this could be confusing as the schema name may by extracted from that at the beginning of CreateSchemaCommand(). This issue exists for a long time, so backpatch down to all the versions supported. Reported-by: Song Hongyu Author: Michael Paquier Reviewed-by: Richard Guo Discussion: https://postgr.es/m/17909-f65c12dfc5f0451d@postgresql.org Backpatch-through: 11
2023-04-28 12:29:12 +02:00
* transformCreateSchemaStmtElements -
* analyzes the elements of a CREATE SCHEMA statement
*
Fix crashes with CREATE SCHEMA AUTHORIZATION and schema elements CREATE SCHEMA AUTHORIZATION with appended schema elements can lead to crashes when comparing the schema name of the query with the schemas used in the qualification of some clauses in the elements' queries. The origin of the problem is that the transformation routine for the elements listed in a CREATE SCHEMA query uses as new, expected, schema name the one listed in CreateSchemaStmt itself. However, depending on the query, CreateSchemaStmt.schemaname may be NULL, being computed instead from the role specification of the query given by the AUTHORIZATION clause, that could be either: - A user name string, with the new schema name being set to the same value as the role given. - Guessed from CURRENT_ROLE, SESSION_ROLE or CURRENT_ROLE, with a new schema name computed from the security context where CREATE SCHEMA is running. Regression tests are added for CREATE SCHEMA with some appended elements (some of them with schema qualifications), covering also some role specification patterns. While on it, this simplifies the context structure used during the transformation of the elements listed in a CREATE SCHEMA query by removing the fields for the role specification and the role type. They were not used, and for the role specification this could be confusing as the schema name may by extracted from that at the beginning of CreateSchemaCommand(). This issue exists for a long time, so backpatch down to all the versions supported. Reported-by: Song Hongyu Author: Michael Paquier Reviewed-by: Richard Guo Discussion: https://postgr.es/m/17909-f65c12dfc5f0451d@postgresql.org Backpatch-through: 11
2023-04-28 12:29:12 +02:00
* Split the schema element list from a CREATE SCHEMA statement into
* individual commands and place them in the result list in an order
* such that there are no forward references (e.g. GRANT to a table
* created later in the list). Note that the logic we use for determining
* forward references is presently quite incomplete.
*
* "schemaName" is the name of the schema that will be used for the creation
* of the objects listed, that may be compiled from the schema name defined
* in the statement or a role specification.
*
* SQL also allows constraints to make forward references, so thumb through
* the table columns and move forward references to a posterior alter-table
* command.
*
* The result is a list of parse nodes that still need to be analyzed ---
* but we can't analyze the later commands until we've executed the earlier
* ones, because of possible inter-object references.
*
* Note: this breaks the rules a little bit by modifying schema-name fields
* within passed-in structs. However, the transformation would be the same
* if done over, so it should be all right to scribble on the input to this
* extent.
*/
List *
Fix crashes with CREATE SCHEMA AUTHORIZATION and schema elements CREATE SCHEMA AUTHORIZATION with appended schema elements can lead to crashes when comparing the schema name of the query with the schemas used in the qualification of some clauses in the elements' queries. The origin of the problem is that the transformation routine for the elements listed in a CREATE SCHEMA query uses as new, expected, schema name the one listed in CreateSchemaStmt itself. However, depending on the query, CreateSchemaStmt.schemaname may be NULL, being computed instead from the role specification of the query given by the AUTHORIZATION clause, that could be either: - A user name string, with the new schema name being set to the same value as the role given. - Guessed from CURRENT_ROLE, SESSION_ROLE or CURRENT_ROLE, with a new schema name computed from the security context where CREATE SCHEMA is running. Regression tests are added for CREATE SCHEMA with some appended elements (some of them with schema qualifications), covering also some role specification patterns. While on it, this simplifies the context structure used during the transformation of the elements listed in a CREATE SCHEMA query by removing the fields for the role specification and the role type. They were not used, and for the role specification this could be confusing as the schema name may by extracted from that at the beginning of CreateSchemaCommand(). This issue exists for a long time, so backpatch down to all the versions supported. Reported-by: Song Hongyu Author: Michael Paquier Reviewed-by: Richard Guo Discussion: https://postgr.es/m/17909-f65c12dfc5f0451d@postgresql.org Backpatch-through: 11
2023-04-28 12:29:12 +02:00
transformCreateSchemaStmtElements(List *schemaElts, const char *schemaName)
{
CreateSchemaStmtContext cxt;
List *result;
ListCell *elements;
Fix crashes with CREATE SCHEMA AUTHORIZATION and schema elements CREATE SCHEMA AUTHORIZATION with appended schema elements can lead to crashes when comparing the schema name of the query with the schemas used in the qualification of some clauses in the elements' queries. The origin of the problem is that the transformation routine for the elements listed in a CREATE SCHEMA query uses as new, expected, schema name the one listed in CreateSchemaStmt itself. However, depending on the query, CreateSchemaStmt.schemaname may be NULL, being computed instead from the role specification of the query given by the AUTHORIZATION clause, that could be either: - A user name string, with the new schema name being set to the same value as the role given. - Guessed from CURRENT_ROLE, SESSION_ROLE or CURRENT_ROLE, with a new schema name computed from the security context where CREATE SCHEMA is running. Regression tests are added for CREATE SCHEMA with some appended elements (some of them with schema qualifications), covering also some role specification patterns. While on it, this simplifies the context structure used during the transformation of the elements listed in a CREATE SCHEMA query by removing the fields for the role specification and the role type. They were not used, and for the role specification this could be confusing as the schema name may by extracted from that at the beginning of CreateSchemaCommand(). This issue exists for a long time, so backpatch down to all the versions supported. Reported-by: Song Hongyu Author: Michael Paquier Reviewed-by: Richard Guo Discussion: https://postgr.es/m/17909-f65c12dfc5f0451d@postgresql.org Backpatch-through: 11
2023-04-28 12:29:12 +02:00
cxt.schemaname = schemaName;
cxt.sequences = NIL;
cxt.tables = NIL;
cxt.views = NIL;
cxt.indexes = NIL;
cxt.triggers = NIL;
cxt.grants = NIL;
/*
* Run through each schema element in the schema element list. Separate
* statements by type, and do preliminary analysis.
*/
Fix crashes with CREATE SCHEMA AUTHORIZATION and schema elements CREATE SCHEMA AUTHORIZATION with appended schema elements can lead to crashes when comparing the schema name of the query with the schemas used in the qualification of some clauses in the elements' queries. The origin of the problem is that the transformation routine for the elements listed in a CREATE SCHEMA query uses as new, expected, schema name the one listed in CreateSchemaStmt itself. However, depending on the query, CreateSchemaStmt.schemaname may be NULL, being computed instead from the role specification of the query given by the AUTHORIZATION clause, that could be either: - A user name string, with the new schema name being set to the same value as the role given. - Guessed from CURRENT_ROLE, SESSION_ROLE or CURRENT_ROLE, with a new schema name computed from the security context where CREATE SCHEMA is running. Regression tests are added for CREATE SCHEMA with some appended elements (some of them with schema qualifications), covering also some role specification patterns. While on it, this simplifies the context structure used during the transformation of the elements listed in a CREATE SCHEMA query by removing the fields for the role specification and the role type. They were not used, and for the role specification this could be confusing as the schema name may by extracted from that at the beginning of CreateSchemaCommand(). This issue exists for a long time, so backpatch down to all the versions supported. Reported-by: Song Hongyu Author: Michael Paquier Reviewed-by: Richard Guo Discussion: https://postgr.es/m/17909-f65c12dfc5f0451d@postgresql.org Backpatch-through: 11
2023-04-28 12:29:12 +02:00
foreach(elements, schemaElts)
{
Node *element = lfirst(elements);
switch (nodeTag(element))
{
case T_CreateSeqStmt:
{
CreateSeqStmt *elp = (CreateSeqStmt *) element;
setSchemaName(cxt.schemaname, &elp->sequence->schemaname);
cxt.sequences = lappend(cxt.sequences, element);
}
break;
case T_CreateStmt:
{
CreateStmt *elp = (CreateStmt *) element;
setSchemaName(cxt.schemaname, &elp->relation->schemaname);
/*
* XXX todo: deal with constraints
*/
cxt.tables = lappend(cxt.tables, element);
}
break;
case T_ViewStmt:
{
ViewStmt *elp = (ViewStmt *) element;
setSchemaName(cxt.schemaname, &elp->view->schemaname);
/*
* XXX todo: deal with references between views
*/
cxt.views = lappend(cxt.views, element);
}
break;
case T_IndexStmt:
{
IndexStmt *elp = (IndexStmt *) element;
setSchemaName(cxt.schemaname, &elp->relation->schemaname);
cxt.indexes = lappend(cxt.indexes, element);
}
break;
case T_CreateTrigStmt:
{
CreateTrigStmt *elp = (CreateTrigStmt *) element;
setSchemaName(cxt.schemaname, &elp->relation->schemaname);
cxt.triggers = lappend(cxt.triggers, element);
}
break;
case T_GrantStmt:
cxt.grants = lappend(cxt.grants, element);
break;
default:
elog(ERROR, "unrecognized node type: %d",
(int) nodeTag(element));
}
}
result = NIL;
result = list_concat(result, cxt.sequences);
result = list_concat(result, cxt.tables);
result = list_concat(result, cxt.views);
result = list_concat(result, cxt.indexes);
result = list_concat(result, cxt.triggers);
result = list_concat(result, cxt.grants);
return result;
}
/*
* setSchemaName
* Set or check schema name in an element of a CREATE SCHEMA command
*/
static void
Fix crashes with CREATE SCHEMA AUTHORIZATION and schema elements CREATE SCHEMA AUTHORIZATION with appended schema elements can lead to crashes when comparing the schema name of the query with the schemas used in the qualification of some clauses in the elements' queries. The origin of the problem is that the transformation routine for the elements listed in a CREATE SCHEMA query uses as new, expected, schema name the one listed in CreateSchemaStmt itself. However, depending on the query, CreateSchemaStmt.schemaname may be NULL, being computed instead from the role specification of the query given by the AUTHORIZATION clause, that could be either: - A user name string, with the new schema name being set to the same value as the role given. - Guessed from CURRENT_ROLE, SESSION_ROLE or CURRENT_ROLE, with a new schema name computed from the security context where CREATE SCHEMA is running. Regression tests are added for CREATE SCHEMA with some appended elements (some of them with schema qualifications), covering also some role specification patterns. While on it, this simplifies the context structure used during the transformation of the elements listed in a CREATE SCHEMA query by removing the fields for the role specification and the role type. They were not used, and for the role specification this could be confusing as the schema name may by extracted from that at the beginning of CreateSchemaCommand(). This issue exists for a long time, so backpatch down to all the versions supported. Reported-by: Song Hongyu Author: Michael Paquier Reviewed-by: Richard Guo Discussion: https://postgr.es/m/17909-f65c12dfc5f0451d@postgresql.org Backpatch-through: 11
2023-04-28 12:29:12 +02:00
setSchemaName(const char *context_schema, char **stmt_schema_name)
{
if (*stmt_schema_name == NULL)
Fix crashes with CREATE SCHEMA AUTHORIZATION and schema elements CREATE SCHEMA AUTHORIZATION with appended schema elements can lead to crashes when comparing the schema name of the query with the schemas used in the qualification of some clauses in the elements' queries. The origin of the problem is that the transformation routine for the elements listed in a CREATE SCHEMA query uses as new, expected, schema name the one listed in CreateSchemaStmt itself. However, depending on the query, CreateSchemaStmt.schemaname may be NULL, being computed instead from the role specification of the query given by the AUTHORIZATION clause, that could be either: - A user name string, with the new schema name being set to the same value as the role given. - Guessed from CURRENT_ROLE, SESSION_ROLE or CURRENT_ROLE, with a new schema name computed from the security context where CREATE SCHEMA is running. Regression tests are added for CREATE SCHEMA with some appended elements (some of them with schema qualifications), covering also some role specification patterns. While on it, this simplifies the context structure used during the transformation of the elements listed in a CREATE SCHEMA query by removing the fields for the role specification and the role type. They were not used, and for the role specification this could be confusing as the schema name may by extracted from that at the beginning of CreateSchemaCommand(). This issue exists for a long time, so backpatch down to all the versions supported. Reported-by: Song Hongyu Author: Michael Paquier Reviewed-by: Richard Guo Discussion: https://postgr.es/m/17909-f65c12dfc5f0451d@postgresql.org Backpatch-through: 11
2023-04-28 12:29:12 +02:00
*stmt_schema_name = unconstify(char *, context_schema);
else if (strcmp(context_schema, *stmt_schema_name) != 0)
ereport(ERROR,
(errcode(ERRCODE_INVALID_SCHEMA_DEFINITION),
errmsg("CREATE specifies a schema (%s) "
"different from the one being created (%s)",
*stmt_schema_name, context_schema)));
}
Implement table partitioning. Table partitioning is like table inheritance and reuses much of the existing infrastructure, but there are some important differences. The parent is called a partitioned table and is always empty; it may not have indexes or non-inherited constraints, since those make no sense for a relation with no data of its own. The children are called partitions and contain all of the actual data. Each partition has an implicit partitioning constraint. Multiple inheritance is not allowed, and partitioning and inheritance can't be mixed. Partitions can't have extra columns and may not allow nulls unless the parent does. Tuples inserted into the parent are automatically routed to the correct partition, so tuple-routing ON INSERT triggers are not needed. Tuple routing isn't yet supported for partitions which are foreign tables, and it doesn't handle updates that cross partition boundaries. Currently, tables can be range-partitioned or list-partitioned. List partitioning is limited to a single column, but range partitioning can involve multiple columns. A partitioning "column" can be an expression. Because table partitioning is less general than table inheritance, it is hoped that it will be easier to reason about properties of partitions, and therefore that this will serve as a better foundation for a variety of possible optimizations, including query planner optimizations. The tuple routing based which this patch does based on the implicit partitioning constraints is an example of this, but it seems likely that many other useful optimizations are also possible. Amit Langote, reviewed and tested by Robert Haas, Ashutosh Bapat, Amit Kapila, Rajkumar Raghuwanshi, Corey Huinker, Jaime Casanova, Rushabh Lathia, Erik Rijkers, among others. Minor revisions by me.
2016-12-07 19:17:43 +01:00
/*
* transformPartitionCmd
* Analyze the ATTACH/DETACH PARTITION command
*
* In case of the ATTACH PARTITION command, cxt->partbound is set to the
* transformed value of cmd->bound.
Implement table partitioning. Table partitioning is like table inheritance and reuses much of the existing infrastructure, but there are some important differences. The parent is called a partitioned table and is always empty; it may not have indexes or non-inherited constraints, since those make no sense for a relation with no data of its own. The children are called partitions and contain all of the actual data. Each partition has an implicit partitioning constraint. Multiple inheritance is not allowed, and partitioning and inheritance can't be mixed. Partitions can't have extra columns and may not allow nulls unless the parent does. Tuples inserted into the parent are automatically routed to the correct partition, so tuple-routing ON INSERT triggers are not needed. Tuple routing isn't yet supported for partitions which are foreign tables, and it doesn't handle updates that cross partition boundaries. Currently, tables can be range-partitioned or list-partitioned. List partitioning is limited to a single column, but range partitioning can involve multiple columns. A partitioning "column" can be an expression. Because table partitioning is less general than table inheritance, it is hoped that it will be easier to reason about properties of partitions, and therefore that this will serve as a better foundation for a variety of possible optimizations, including query planner optimizations. The tuple routing based which this patch does based on the implicit partitioning constraints is an example of this, but it seems likely that many other useful optimizations are also possible. Amit Langote, reviewed and tested by Robert Haas, Ashutosh Bapat, Amit Kapila, Rajkumar Raghuwanshi, Corey Huinker, Jaime Casanova, Rushabh Lathia, Erik Rijkers, among others. Minor revisions by me.
2016-12-07 19:17:43 +01:00
*/
static void
transformPartitionCmd(CreateStmtContext *cxt, PartitionCmd *cmd)
Implement table partitioning. Table partitioning is like table inheritance and reuses much of the existing infrastructure, but there are some important differences. The parent is called a partitioned table and is always empty; it may not have indexes or non-inherited constraints, since those make no sense for a relation with no data of its own. The children are called partitions and contain all of the actual data. Each partition has an implicit partitioning constraint. Multiple inheritance is not allowed, and partitioning and inheritance can't be mixed. Partitions can't have extra columns and may not allow nulls unless the parent does. Tuples inserted into the parent are automatically routed to the correct partition, so tuple-routing ON INSERT triggers are not needed. Tuple routing isn't yet supported for partitions which are foreign tables, and it doesn't handle updates that cross partition boundaries. Currently, tables can be range-partitioned or list-partitioned. List partitioning is limited to a single column, but range partitioning can involve multiple columns. A partitioning "column" can be an expression. Because table partitioning is less general than table inheritance, it is hoped that it will be easier to reason about properties of partitions, and therefore that this will serve as a better foundation for a variety of possible optimizations, including query planner optimizations. The tuple routing based which this patch does based on the implicit partitioning constraints is an example of this, but it seems likely that many other useful optimizations are also possible. Amit Langote, reviewed and tested by Robert Haas, Ashutosh Bapat, Amit Kapila, Rajkumar Raghuwanshi, Corey Huinker, Jaime Casanova, Rushabh Lathia, Erik Rijkers, among others. Minor revisions by me.
2016-12-07 19:17:43 +01:00
{
Relation parentRel = cxt->rel;
switch (parentRel->rd_rel->relkind)
{
case RELKIND_PARTITIONED_TABLE:
/* transform the partition bound, if any */
Assert(RelationGetPartitionKey(parentRel) != NULL);
if (cmd->bound != NULL)
cxt->partbound = transformPartitionBound(cxt->pstate, parentRel,
cmd->bound);
break;
case RELKIND_PARTITIONED_INDEX:
/*
* A partitioned index cannot have a partition bound set. ALTER
* INDEX prevents that with its grammar, but not ALTER TABLE.
*/
if (cmd->bound != NULL)
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("\"%s\" is not a partitioned table",
RelationGetRelationName(parentRel))));
break;
case RELKIND_RELATION:
/* the table must be partitioned */
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("table \"%s\" is not partitioned",
RelationGetRelationName(parentRel))));
break;
case RELKIND_INDEX:
/* the index must be partitioned */
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("index \"%s\" is not partitioned",
RelationGetRelationName(parentRel))));
break;
default:
/* parser shouldn't let this case through */
elog(ERROR, "\"%s\" is not a partitioned table or index",
RelationGetRelationName(parentRel));
break;
}
Implement table partitioning. Table partitioning is like table inheritance and reuses much of the existing infrastructure, but there are some important differences. The parent is called a partitioned table and is always empty; it may not have indexes or non-inherited constraints, since those make no sense for a relation with no data of its own. The children are called partitions and contain all of the actual data. Each partition has an implicit partitioning constraint. Multiple inheritance is not allowed, and partitioning and inheritance can't be mixed. Partitions can't have extra columns and may not allow nulls unless the parent does. Tuples inserted into the parent are automatically routed to the correct partition, so tuple-routing ON INSERT triggers are not needed. Tuple routing isn't yet supported for partitions which are foreign tables, and it doesn't handle updates that cross partition boundaries. Currently, tables can be range-partitioned or list-partitioned. List partitioning is limited to a single column, but range partitioning can involve multiple columns. A partitioning "column" can be an expression. Because table partitioning is less general than table inheritance, it is hoped that it will be easier to reason about properties of partitions, and therefore that this will serve as a better foundation for a variety of possible optimizations, including query planner optimizations. The tuple routing based which this patch does based on the implicit partitioning constraints is an example of this, but it seems likely that many other useful optimizations are also possible. Amit Langote, reviewed and tested by Robert Haas, Ashutosh Bapat, Amit Kapila, Rajkumar Raghuwanshi, Corey Huinker, Jaime Casanova, Rushabh Lathia, Erik Rijkers, among others. Minor revisions by me.
2016-12-07 19:17:43 +01:00
}
/*
* transformPartitionBound
*
Code review focused on new node types added by partitioning support. Fix failure to check that we got a plain Const from const-simplification of a coercion request. This is the cause of bug #14666 from Tian Bing: there is an int4 to money cast, but it's only stable not immutable (because of dependence on lc_monetary), resulting in a FuncExpr that the code was miserably unequipped to deal with, or indeed even to notice that it was failing to deal with. Add test cases around this coercion behavior. In view of the above, sprinkle the code liberally with castNode() macros, in hope of catching the next such bug a bit sooner. Also, change some functions that were randomly declared to take Node* to take more specific pointer types. And change some struct fields that were declared Node* but could be given more specific types, allowing removal of assorted explicit casts. Place PARTITION_MAX_KEYS check a bit closer to the code it's protecting. Likewise check only-one-key-for-list-partitioning restriction in a less random place. Avoid not-per-project-style usages like !strcmp(...). Fix assorted failures to avoid scribbling on the input of parse transformation. I'm not sure how necessary this is, but it's entirely silly for these functions to be expending cycles to avoid that and not getting it right. Add guards against partitioning on system columns. Put backend/nodes/ support code into an order that matches handling of these node types elsewhere. Annotate the fact that somebody added location fields to PartitionBoundSpec and PartitionRangeDatum but forgot to handle them in outfuncs.c/readfuncs.c. This is fairly harmless for production purposes (since readfuncs.c would just substitute -1 anyway) but it's still bogus. It's not worth forcing a post-beta1 initdb just to fix this, but if we have another reason to force initdb before 10.0, we should go back and clean this up. Contrariwise, somebody added location fields to PartitionElem and PartitionSpec but forgot to teach exprLocation() about them. Consolidate duplicative code in transformPartitionBound(). Improve a couple of error messages. Improve assorted commentary. Re-pgindent the files touched by this patch; this affects a few comment blocks that must have been added quite recently. Report: https://postgr.es/m/20170524024550.29935.14396@wrigleys.postgresql.org
2017-05-29 05:20:28 +02:00
* Transform a partition bound specification
Implement table partitioning. Table partitioning is like table inheritance and reuses much of the existing infrastructure, but there are some important differences. The parent is called a partitioned table and is always empty; it may not have indexes or non-inherited constraints, since those make no sense for a relation with no data of its own. The children are called partitions and contain all of the actual data. Each partition has an implicit partitioning constraint. Multiple inheritance is not allowed, and partitioning and inheritance can't be mixed. Partitions can't have extra columns and may not allow nulls unless the parent does. Tuples inserted into the parent are automatically routed to the correct partition, so tuple-routing ON INSERT triggers are not needed. Tuple routing isn't yet supported for partitions which are foreign tables, and it doesn't handle updates that cross partition boundaries. Currently, tables can be range-partitioned or list-partitioned. List partitioning is limited to a single column, but range partitioning can involve multiple columns. A partitioning "column" can be an expression. Because table partitioning is less general than table inheritance, it is hoped that it will be easier to reason about properties of partitions, and therefore that this will serve as a better foundation for a variety of possible optimizations, including query planner optimizations. The tuple routing based which this patch does based on the implicit partitioning constraints is an example of this, but it seems likely that many other useful optimizations are also possible. Amit Langote, reviewed and tested by Robert Haas, Ashutosh Bapat, Amit Kapila, Rajkumar Raghuwanshi, Corey Huinker, Jaime Casanova, Rushabh Lathia, Erik Rijkers, among others. Minor revisions by me.
2016-12-07 19:17:43 +01:00
*/
Code review focused on new node types added by partitioning support. Fix failure to check that we got a plain Const from const-simplification of a coercion request. This is the cause of bug #14666 from Tian Bing: there is an int4 to money cast, but it's only stable not immutable (because of dependence on lc_monetary), resulting in a FuncExpr that the code was miserably unequipped to deal with, or indeed even to notice that it was failing to deal with. Add test cases around this coercion behavior. In view of the above, sprinkle the code liberally with castNode() macros, in hope of catching the next such bug a bit sooner. Also, change some functions that were randomly declared to take Node* to take more specific pointer types. And change some struct fields that were declared Node* but could be given more specific types, allowing removal of assorted explicit casts. Place PARTITION_MAX_KEYS check a bit closer to the code it's protecting. Likewise check only-one-key-for-list-partitioning restriction in a less random place. Avoid not-per-project-style usages like !strcmp(...). Fix assorted failures to avoid scribbling on the input of parse transformation. I'm not sure how necessary this is, but it's entirely silly for these functions to be expending cycles to avoid that and not getting it right. Add guards against partitioning on system columns. Put backend/nodes/ support code into an order that matches handling of these node types elsewhere. Annotate the fact that somebody added location fields to PartitionBoundSpec and PartitionRangeDatum but forgot to handle them in outfuncs.c/readfuncs.c. This is fairly harmless for production purposes (since readfuncs.c would just substitute -1 anyway) but it's still bogus. It's not worth forcing a post-beta1 initdb just to fix this, but if we have another reason to force initdb before 10.0, we should go back and clean this up. Contrariwise, somebody added location fields to PartitionElem and PartitionSpec but forgot to teach exprLocation() about them. Consolidate duplicative code in transformPartitionBound(). Improve a couple of error messages. Improve assorted commentary. Re-pgindent the files touched by this patch; this affects a few comment blocks that must have been added quite recently. Report: https://postgr.es/m/20170524024550.29935.14396@wrigleys.postgresql.org
2017-05-29 05:20:28 +02:00
PartitionBoundSpec *
transformPartitionBound(ParseState *pstate, Relation parent,
PartitionBoundSpec *spec)
Implement table partitioning. Table partitioning is like table inheritance and reuses much of the existing infrastructure, but there are some important differences. The parent is called a partitioned table and is always empty; it may not have indexes or non-inherited constraints, since those make no sense for a relation with no data of its own. The children are called partitions and contain all of the actual data. Each partition has an implicit partitioning constraint. Multiple inheritance is not allowed, and partitioning and inheritance can't be mixed. Partitions can't have extra columns and may not allow nulls unless the parent does. Tuples inserted into the parent are automatically routed to the correct partition, so tuple-routing ON INSERT triggers are not needed. Tuple routing isn't yet supported for partitions which are foreign tables, and it doesn't handle updates that cross partition boundaries. Currently, tables can be range-partitioned or list-partitioned. List partitioning is limited to a single column, but range partitioning can involve multiple columns. A partitioning "column" can be an expression. Because table partitioning is less general than table inheritance, it is hoped that it will be easier to reason about properties of partitions, and therefore that this will serve as a better foundation for a variety of possible optimizations, including query planner optimizations. The tuple routing based which this patch does based on the implicit partitioning constraints is an example of this, but it seems likely that many other useful optimizations are also possible. Amit Langote, reviewed and tested by Robert Haas, Ashutosh Bapat, Amit Kapila, Rajkumar Raghuwanshi, Corey Huinker, Jaime Casanova, Rushabh Lathia, Erik Rijkers, among others. Minor revisions by me.
2016-12-07 19:17:43 +01:00
{
Code review focused on new node types added by partitioning support. Fix failure to check that we got a plain Const from const-simplification of a coercion request. This is the cause of bug #14666 from Tian Bing: there is an int4 to money cast, but it's only stable not immutable (because of dependence on lc_monetary), resulting in a FuncExpr that the code was miserably unequipped to deal with, or indeed even to notice that it was failing to deal with. Add test cases around this coercion behavior. In view of the above, sprinkle the code liberally with castNode() macros, in hope of catching the next such bug a bit sooner. Also, change some functions that were randomly declared to take Node* to take more specific pointer types. And change some struct fields that were declared Node* but could be given more specific types, allowing removal of assorted explicit casts. Place PARTITION_MAX_KEYS check a bit closer to the code it's protecting. Likewise check only-one-key-for-list-partitioning restriction in a less random place. Avoid not-per-project-style usages like !strcmp(...). Fix assorted failures to avoid scribbling on the input of parse transformation. I'm not sure how necessary this is, but it's entirely silly for these functions to be expending cycles to avoid that and not getting it right. Add guards against partitioning on system columns. Put backend/nodes/ support code into an order that matches handling of these node types elsewhere. Annotate the fact that somebody added location fields to PartitionBoundSpec and PartitionRangeDatum but forgot to handle them in outfuncs.c/readfuncs.c. This is fairly harmless for production purposes (since readfuncs.c would just substitute -1 anyway) but it's still bogus. It's not worth forcing a post-beta1 initdb just to fix this, but if we have another reason to force initdb before 10.0, we should go back and clean this up. Contrariwise, somebody added location fields to PartitionElem and PartitionSpec but forgot to teach exprLocation() about them. Consolidate duplicative code in transformPartitionBound(). Improve a couple of error messages. Improve assorted commentary. Re-pgindent the files touched by this patch; this affects a few comment blocks that must have been added quite recently. Report: https://postgr.es/m/20170524024550.29935.14396@wrigleys.postgresql.org
2017-05-29 05:20:28 +02:00
PartitionBoundSpec *result_spec;
Implement table partitioning. Table partitioning is like table inheritance and reuses much of the existing infrastructure, but there are some important differences. The parent is called a partitioned table and is always empty; it may not have indexes or non-inherited constraints, since those make no sense for a relation with no data of its own. The children are called partitions and contain all of the actual data. Each partition has an implicit partitioning constraint. Multiple inheritance is not allowed, and partitioning and inheritance can't be mixed. Partitions can't have extra columns and may not allow nulls unless the parent does. Tuples inserted into the parent are automatically routed to the correct partition, so tuple-routing ON INSERT triggers are not needed. Tuple routing isn't yet supported for partitions which are foreign tables, and it doesn't handle updates that cross partition boundaries. Currently, tables can be range-partitioned or list-partitioned. List partitioning is limited to a single column, but range partitioning can involve multiple columns. A partitioning "column" can be an expression. Because table partitioning is less general than table inheritance, it is hoped that it will be easier to reason about properties of partitions, and therefore that this will serve as a better foundation for a variety of possible optimizations, including query planner optimizations. The tuple routing based which this patch does based on the implicit partitioning constraints is an example of this, but it seems likely that many other useful optimizations are also possible. Amit Langote, reviewed and tested by Robert Haas, Ashutosh Bapat, Amit Kapila, Rajkumar Raghuwanshi, Corey Huinker, Jaime Casanova, Rushabh Lathia, Erik Rijkers, among others. Minor revisions by me.
2016-12-07 19:17:43 +01:00
PartitionKey key = RelationGetPartitionKey(parent);
char strategy = get_partition_strategy(key);
int partnatts = get_partition_natts(key);
List *partexprs = get_partition_exprs(key);
Code review focused on new node types added by partitioning support. Fix failure to check that we got a plain Const from const-simplification of a coercion request. This is the cause of bug #14666 from Tian Bing: there is an int4 to money cast, but it's only stable not immutable (because of dependence on lc_monetary), resulting in a FuncExpr that the code was miserably unequipped to deal with, or indeed even to notice that it was failing to deal with. Add test cases around this coercion behavior. In view of the above, sprinkle the code liberally with castNode() macros, in hope of catching the next such bug a bit sooner. Also, change some functions that were randomly declared to take Node* to take more specific pointer types. And change some struct fields that were declared Node* but could be given more specific types, allowing removal of assorted explicit casts. Place PARTITION_MAX_KEYS check a bit closer to the code it's protecting. Likewise check only-one-key-for-list-partitioning restriction in a less random place. Avoid not-per-project-style usages like !strcmp(...). Fix assorted failures to avoid scribbling on the input of parse transformation. I'm not sure how necessary this is, but it's entirely silly for these functions to be expending cycles to avoid that and not getting it right. Add guards against partitioning on system columns. Put backend/nodes/ support code into an order that matches handling of these node types elsewhere. Annotate the fact that somebody added location fields to PartitionBoundSpec and PartitionRangeDatum but forgot to handle them in outfuncs.c/readfuncs.c. This is fairly harmless for production purposes (since readfuncs.c would just substitute -1 anyway) but it's still bogus. It's not worth forcing a post-beta1 initdb just to fix this, but if we have another reason to force initdb before 10.0, we should go back and clean this up. Contrariwise, somebody added location fields to PartitionElem and PartitionSpec but forgot to teach exprLocation() about them. Consolidate duplicative code in transformPartitionBound(). Improve a couple of error messages. Improve assorted commentary. Re-pgindent the files touched by this patch; this affects a few comment blocks that must have been added quite recently. Report: https://postgr.es/m/20170524024550.29935.14396@wrigleys.postgresql.org
2017-05-29 05:20:28 +02:00
/* Avoid scribbling on input */
Implement table partitioning. Table partitioning is like table inheritance and reuses much of the existing infrastructure, but there are some important differences. The parent is called a partitioned table and is always empty; it may not have indexes or non-inherited constraints, since those make no sense for a relation with no data of its own. The children are called partitions and contain all of the actual data. Each partition has an implicit partitioning constraint. Multiple inheritance is not allowed, and partitioning and inheritance can't be mixed. Partitions can't have extra columns and may not allow nulls unless the parent does. Tuples inserted into the parent are automatically routed to the correct partition, so tuple-routing ON INSERT triggers are not needed. Tuple routing isn't yet supported for partitions which are foreign tables, and it doesn't handle updates that cross partition boundaries. Currently, tables can be range-partitioned or list-partitioned. List partitioning is limited to a single column, but range partitioning can involve multiple columns. A partitioning "column" can be an expression. Because table partitioning is less general than table inheritance, it is hoped that it will be easier to reason about properties of partitions, and therefore that this will serve as a better foundation for a variety of possible optimizations, including query planner optimizations. The tuple routing based which this patch does based on the implicit partitioning constraints is an example of this, but it seems likely that many other useful optimizations are also possible. Amit Langote, reviewed and tested by Robert Haas, Ashutosh Bapat, Amit Kapila, Rajkumar Raghuwanshi, Corey Huinker, Jaime Casanova, Rushabh Lathia, Erik Rijkers, among others. Minor revisions by me.
2016-12-07 19:17:43 +01:00
result_spec = copyObject(spec);
if (spec->is_default)
{
/*
* Hash partitioning does not support a default partition; there's no
* use case for it (since the set of partitions to create is perfectly
* defined), and if users do get into it accidentally, it's hard to
* back out from it afterwards.
*/
if (strategy == PARTITION_STRATEGY_HASH)
ereport(ERROR,
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
errmsg("a hash-partitioned table may not have a default partition")));
/*
* In case of the default partition, parser had no way to identify the
* partition strategy. Assign the parent's strategy to the default
* partition bound spec.
*/
result_spec->strategy = strategy;
return result_spec;
}
if (strategy == PARTITION_STRATEGY_HASH)
{
if (spec->strategy != PARTITION_STRATEGY_HASH)
ereport(ERROR,
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
errmsg("invalid bound specification for a hash partition"),
parser_errposition(pstate, exprLocation((Node *) spec))));
if (spec->modulus <= 0)
ereport(ERROR,
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
errmsg("modulus for hash partition must be an integer value greater than zero")));
Assert(spec->remainder >= 0);
if (spec->remainder >= spec->modulus)
ereport(ERROR,
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
errmsg("remainder for hash partition must be less than modulus")));
}
else if (strategy == PARTITION_STRATEGY_LIST)
Implement table partitioning. Table partitioning is like table inheritance and reuses much of the existing infrastructure, but there are some important differences. The parent is called a partitioned table and is always empty; it may not have indexes or non-inherited constraints, since those make no sense for a relation with no data of its own. The children are called partitions and contain all of the actual data. Each partition has an implicit partitioning constraint. Multiple inheritance is not allowed, and partitioning and inheritance can't be mixed. Partitions can't have extra columns and may not allow nulls unless the parent does. Tuples inserted into the parent are automatically routed to the correct partition, so tuple-routing ON INSERT triggers are not needed. Tuple routing isn't yet supported for partitions which are foreign tables, and it doesn't handle updates that cross partition boundaries. Currently, tables can be range-partitioned or list-partitioned. List partitioning is limited to a single column, but range partitioning can involve multiple columns. A partitioning "column" can be an expression. Because table partitioning is less general than table inheritance, it is hoped that it will be easier to reason about properties of partitions, and therefore that this will serve as a better foundation for a variety of possible optimizations, including query planner optimizations. The tuple routing based which this patch does based on the implicit partitioning constraints is an example of this, but it seems likely that many other useful optimizations are also possible. Amit Langote, reviewed and tested by Robert Haas, Ashutosh Bapat, Amit Kapila, Rajkumar Raghuwanshi, Corey Huinker, Jaime Casanova, Rushabh Lathia, Erik Rijkers, among others. Minor revisions by me.
2016-12-07 19:17:43 +01:00
{
ListCell *cell;
char *colname;
Code review focused on new node types added by partitioning support. Fix failure to check that we got a plain Const from const-simplification of a coercion request. This is the cause of bug #14666 from Tian Bing: there is an int4 to money cast, but it's only stable not immutable (because of dependence on lc_monetary), resulting in a FuncExpr that the code was miserably unequipped to deal with, or indeed even to notice that it was failing to deal with. Add test cases around this coercion behavior. In view of the above, sprinkle the code liberally with castNode() macros, in hope of catching the next such bug a bit sooner. Also, change some functions that were randomly declared to take Node* to take more specific pointer types. And change some struct fields that were declared Node* but could be given more specific types, allowing removal of assorted explicit casts. Place PARTITION_MAX_KEYS check a bit closer to the code it's protecting. Likewise check only-one-key-for-list-partitioning restriction in a less random place. Avoid not-per-project-style usages like !strcmp(...). Fix assorted failures to avoid scribbling on the input of parse transformation. I'm not sure how necessary this is, but it's entirely silly for these functions to be expending cycles to avoid that and not getting it right. Add guards against partitioning on system columns. Put backend/nodes/ support code into an order that matches handling of these node types elsewhere. Annotate the fact that somebody added location fields to PartitionBoundSpec and PartitionRangeDatum but forgot to handle them in outfuncs.c/readfuncs.c. This is fairly harmless for production purposes (since readfuncs.c would just substitute -1 anyway) but it's still bogus. It's not worth forcing a post-beta1 initdb just to fix this, but if we have another reason to force initdb before 10.0, we should go back and clean this up. Contrariwise, somebody added location fields to PartitionElem and PartitionSpec but forgot to teach exprLocation() about them. Consolidate duplicative code in transformPartitionBound(). Improve a couple of error messages. Improve assorted commentary. Re-pgindent the files touched by this patch; this affects a few comment blocks that must have been added quite recently. Report: https://postgr.es/m/20170524024550.29935.14396@wrigleys.postgresql.org
2017-05-29 05:20:28 +02:00
Oid coltype;
int32 coltypmod;
Oid partcollation;
Code review focused on new node types added by partitioning support. Fix failure to check that we got a plain Const from const-simplification of a coercion request. This is the cause of bug #14666 from Tian Bing: there is an int4 to money cast, but it's only stable not immutable (because of dependence on lc_monetary), resulting in a FuncExpr that the code was miserably unequipped to deal with, or indeed even to notice that it was failing to deal with. Add test cases around this coercion behavior. In view of the above, sprinkle the code liberally with castNode() macros, in hope of catching the next such bug a bit sooner. Also, change some functions that were randomly declared to take Node* to take more specific pointer types. And change some struct fields that were declared Node* but could be given more specific types, allowing removal of assorted explicit casts. Place PARTITION_MAX_KEYS check a bit closer to the code it's protecting. Likewise check only-one-key-for-list-partitioning restriction in a less random place. Avoid not-per-project-style usages like !strcmp(...). Fix assorted failures to avoid scribbling on the input of parse transformation. I'm not sure how necessary this is, but it's entirely silly for these functions to be expending cycles to avoid that and not getting it right. Add guards against partitioning on system columns. Put backend/nodes/ support code into an order that matches handling of these node types elsewhere. Annotate the fact that somebody added location fields to PartitionBoundSpec and PartitionRangeDatum but forgot to handle them in outfuncs.c/readfuncs.c. This is fairly harmless for production purposes (since readfuncs.c would just substitute -1 anyway) but it's still bogus. It's not worth forcing a post-beta1 initdb just to fix this, but if we have another reason to force initdb before 10.0, we should go back and clean this up. Contrariwise, somebody added location fields to PartitionElem and PartitionSpec but forgot to teach exprLocation() about them. Consolidate duplicative code in transformPartitionBound(). Improve a couple of error messages. Improve assorted commentary. Re-pgindent the files touched by this patch; this affects a few comment blocks that must have been added quite recently. Report: https://postgr.es/m/20170524024550.29935.14396@wrigleys.postgresql.org
2017-05-29 05:20:28 +02:00
if (spec->strategy != PARTITION_STRATEGY_LIST)
ereport(ERROR,
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
errmsg("invalid bound specification for a list partition"),
parser_errposition(pstate, exprLocation((Node *) spec))));
Implement table partitioning. Table partitioning is like table inheritance and reuses much of the existing infrastructure, but there are some important differences. The parent is called a partitioned table and is always empty; it may not have indexes or non-inherited constraints, since those make no sense for a relation with no data of its own. The children are called partitions and contain all of the actual data. Each partition has an implicit partitioning constraint. Multiple inheritance is not allowed, and partitioning and inheritance can't be mixed. Partitions can't have extra columns and may not allow nulls unless the parent does. Tuples inserted into the parent are automatically routed to the correct partition, so tuple-routing ON INSERT triggers are not needed. Tuple routing isn't yet supported for partitions which are foreign tables, and it doesn't handle updates that cross partition boundaries. Currently, tables can be range-partitioned or list-partitioned. List partitioning is limited to a single column, but range partitioning can involve multiple columns. A partitioning "column" can be an expression. Because table partitioning is less general than table inheritance, it is hoped that it will be easier to reason about properties of partitions, and therefore that this will serve as a better foundation for a variety of possible optimizations, including query planner optimizations. The tuple routing based which this patch does based on the implicit partitioning constraints is an example of this, but it seems likely that many other useful optimizations are also possible. Amit Langote, reviewed and tested by Robert Haas, Ashutosh Bapat, Amit Kapila, Rajkumar Raghuwanshi, Corey Huinker, Jaime Casanova, Rushabh Lathia, Erik Rijkers, among others. Minor revisions by me.
2016-12-07 19:17:43 +01:00
/* Get the only column's name in case we need to output an error */
if (key->partattrs[0] != 0)
colname = get_attname(RelationGetRelid(parent),
key->partattrs[0], false);
Implement table partitioning. Table partitioning is like table inheritance and reuses much of the existing infrastructure, but there are some important differences. The parent is called a partitioned table and is always empty; it may not have indexes or non-inherited constraints, since those make no sense for a relation with no data of its own. The children are called partitions and contain all of the actual data. Each partition has an implicit partitioning constraint. Multiple inheritance is not allowed, and partitioning and inheritance can't be mixed. Partitions can't have extra columns and may not allow nulls unless the parent does. Tuples inserted into the parent are automatically routed to the correct partition, so tuple-routing ON INSERT triggers are not needed. Tuple routing isn't yet supported for partitions which are foreign tables, and it doesn't handle updates that cross partition boundaries. Currently, tables can be range-partitioned or list-partitioned. List partitioning is limited to a single column, but range partitioning can involve multiple columns. A partitioning "column" can be an expression. Because table partitioning is less general than table inheritance, it is hoped that it will be easier to reason about properties of partitions, and therefore that this will serve as a better foundation for a variety of possible optimizations, including query planner optimizations. The tuple routing based which this patch does based on the implicit partitioning constraints is an example of this, but it seems likely that many other useful optimizations are also possible. Amit Langote, reviewed and tested by Robert Haas, Ashutosh Bapat, Amit Kapila, Rajkumar Raghuwanshi, Corey Huinker, Jaime Casanova, Rushabh Lathia, Erik Rijkers, among others. Minor revisions by me.
2016-12-07 19:17:43 +01:00
else
colname = deparse_expression((Node *) linitial(partexprs),
deparse_context_for(RelationGetRelationName(parent),
RelationGetRelid(parent)),
false, false);
Code review focused on new node types added by partitioning support. Fix failure to check that we got a plain Const from const-simplification of a coercion request. This is the cause of bug #14666 from Tian Bing: there is an int4 to money cast, but it's only stable not immutable (because of dependence on lc_monetary), resulting in a FuncExpr that the code was miserably unequipped to deal with, or indeed even to notice that it was failing to deal with. Add test cases around this coercion behavior. In view of the above, sprinkle the code liberally with castNode() macros, in hope of catching the next such bug a bit sooner. Also, change some functions that were randomly declared to take Node* to take more specific pointer types. And change some struct fields that were declared Node* but could be given more specific types, allowing removal of assorted explicit casts. Place PARTITION_MAX_KEYS check a bit closer to the code it's protecting. Likewise check only-one-key-for-list-partitioning restriction in a less random place. Avoid not-per-project-style usages like !strcmp(...). Fix assorted failures to avoid scribbling on the input of parse transformation. I'm not sure how necessary this is, but it's entirely silly for these functions to be expending cycles to avoid that and not getting it right. Add guards against partitioning on system columns. Put backend/nodes/ support code into an order that matches handling of these node types elsewhere. Annotate the fact that somebody added location fields to PartitionBoundSpec and PartitionRangeDatum but forgot to handle them in outfuncs.c/readfuncs.c. This is fairly harmless for production purposes (since readfuncs.c would just substitute -1 anyway) but it's still bogus. It's not worth forcing a post-beta1 initdb just to fix this, but if we have another reason to force initdb before 10.0, we should go back and clean this up. Contrariwise, somebody added location fields to PartitionElem and PartitionSpec but forgot to teach exprLocation() about them. Consolidate duplicative code in transformPartitionBound(). Improve a couple of error messages. Improve assorted commentary. Re-pgindent the files touched by this patch; this affects a few comment blocks that must have been added quite recently. Report: https://postgr.es/m/20170524024550.29935.14396@wrigleys.postgresql.org
2017-05-29 05:20:28 +02:00
/* Need its type data too */
coltype = get_partition_col_typid(key, 0);
coltypmod = get_partition_col_typmod(key, 0);
partcollation = get_partition_col_collation(key, 0);
Implement table partitioning. Table partitioning is like table inheritance and reuses much of the existing infrastructure, but there are some important differences. The parent is called a partitioned table and is always empty; it may not have indexes or non-inherited constraints, since those make no sense for a relation with no data of its own. The children are called partitions and contain all of the actual data. Each partition has an implicit partitioning constraint. Multiple inheritance is not allowed, and partitioning and inheritance can't be mixed. Partitions can't have extra columns and may not allow nulls unless the parent does. Tuples inserted into the parent are automatically routed to the correct partition, so tuple-routing ON INSERT triggers are not needed. Tuple routing isn't yet supported for partitions which are foreign tables, and it doesn't handle updates that cross partition boundaries. Currently, tables can be range-partitioned or list-partitioned. List partitioning is limited to a single column, but range partitioning can involve multiple columns. A partitioning "column" can be an expression. Because table partitioning is less general than table inheritance, it is hoped that it will be easier to reason about properties of partitions, and therefore that this will serve as a better foundation for a variety of possible optimizations, including query planner optimizations. The tuple routing based which this patch does based on the implicit partitioning constraints is an example of this, but it seems likely that many other useful optimizations are also possible. Amit Langote, reviewed and tested by Robert Haas, Ashutosh Bapat, Amit Kapila, Rajkumar Raghuwanshi, Corey Huinker, Jaime Casanova, Rushabh Lathia, Erik Rijkers, among others. Minor revisions by me.
2016-12-07 19:17:43 +01:00
result_spec->listdatums = NIL;
foreach(cell, spec->listdatums)
{
Node *expr = lfirst(cell);
Code review focused on new node types added by partitioning support. Fix failure to check that we got a plain Const from const-simplification of a coercion request. This is the cause of bug #14666 from Tian Bing: there is an int4 to money cast, but it's only stable not immutable (because of dependence on lc_monetary), resulting in a FuncExpr that the code was miserably unequipped to deal with, or indeed even to notice that it was failing to deal with. Add test cases around this coercion behavior. In view of the above, sprinkle the code liberally with castNode() macros, in hope of catching the next such bug a bit sooner. Also, change some functions that were randomly declared to take Node* to take more specific pointer types. And change some struct fields that were declared Node* but could be given more specific types, allowing removal of assorted explicit casts. Place PARTITION_MAX_KEYS check a bit closer to the code it's protecting. Likewise check only-one-key-for-list-partitioning restriction in a less random place. Avoid not-per-project-style usages like !strcmp(...). Fix assorted failures to avoid scribbling on the input of parse transformation. I'm not sure how necessary this is, but it's entirely silly for these functions to be expending cycles to avoid that and not getting it right. Add guards against partitioning on system columns. Put backend/nodes/ support code into an order that matches handling of these node types elsewhere. Annotate the fact that somebody added location fields to PartitionBoundSpec and PartitionRangeDatum but forgot to handle them in outfuncs.c/readfuncs.c. This is fairly harmless for production purposes (since readfuncs.c would just substitute -1 anyway) but it's still bogus. It's not worth forcing a post-beta1 initdb just to fix this, but if we have another reason to force initdb before 10.0, we should go back and clean this up. Contrariwise, somebody added location fields to PartitionElem and PartitionSpec but forgot to teach exprLocation() about them. Consolidate duplicative code in transformPartitionBound(). Improve a couple of error messages. Improve assorted commentary. Re-pgindent the files touched by this patch; this affects a few comment blocks that must have been added quite recently. Report: https://postgr.es/m/20170524024550.29935.14396@wrigleys.postgresql.org
2017-05-29 05:20:28 +02:00
Const *value;
Implement table partitioning. Table partitioning is like table inheritance and reuses much of the existing infrastructure, but there are some important differences. The parent is called a partitioned table and is always empty; it may not have indexes or non-inherited constraints, since those make no sense for a relation with no data of its own. The children are called partitions and contain all of the actual data. Each partition has an implicit partitioning constraint. Multiple inheritance is not allowed, and partitioning and inheritance can't be mixed. Partitions can't have extra columns and may not allow nulls unless the parent does. Tuples inserted into the parent are automatically routed to the correct partition, so tuple-routing ON INSERT triggers are not needed. Tuple routing isn't yet supported for partitions which are foreign tables, and it doesn't handle updates that cross partition boundaries. Currently, tables can be range-partitioned or list-partitioned. List partitioning is limited to a single column, but range partitioning can involve multiple columns. A partitioning "column" can be an expression. Because table partitioning is less general than table inheritance, it is hoped that it will be easier to reason about properties of partitions, and therefore that this will serve as a better foundation for a variety of possible optimizations, including query planner optimizations. The tuple routing based which this patch does based on the implicit partitioning constraints is an example of this, but it seems likely that many other useful optimizations are also possible. Amit Langote, reviewed and tested by Robert Haas, Ashutosh Bapat, Amit Kapila, Rajkumar Raghuwanshi, Corey Huinker, Jaime Casanova, Rushabh Lathia, Erik Rijkers, among others. Minor revisions by me.
2016-12-07 19:17:43 +01:00
ListCell *cell2;
bool duplicate;
value = transformPartitionBoundValue(pstate, expr,
colname, coltype, coltypmod,
partcollation);
Implement table partitioning. Table partitioning is like table inheritance and reuses much of the existing infrastructure, but there are some important differences. The parent is called a partitioned table and is always empty; it may not have indexes or non-inherited constraints, since those make no sense for a relation with no data of its own. The children are called partitions and contain all of the actual data. Each partition has an implicit partitioning constraint. Multiple inheritance is not allowed, and partitioning and inheritance can't be mixed. Partitions can't have extra columns and may not allow nulls unless the parent does. Tuples inserted into the parent are automatically routed to the correct partition, so tuple-routing ON INSERT triggers are not needed. Tuple routing isn't yet supported for partitions which are foreign tables, and it doesn't handle updates that cross partition boundaries. Currently, tables can be range-partitioned or list-partitioned. List partitioning is limited to a single column, but range partitioning can involve multiple columns. A partitioning "column" can be an expression. Because table partitioning is less general than table inheritance, it is hoped that it will be easier to reason about properties of partitions, and therefore that this will serve as a better foundation for a variety of possible optimizations, including query planner optimizations. The tuple routing based which this patch does based on the implicit partitioning constraints is an example of this, but it seems likely that many other useful optimizations are also possible. Amit Langote, reviewed and tested by Robert Haas, Ashutosh Bapat, Amit Kapila, Rajkumar Raghuwanshi, Corey Huinker, Jaime Casanova, Rushabh Lathia, Erik Rijkers, among others. Minor revisions by me.
2016-12-07 19:17:43 +01:00
/* Don't add to the result if the value is a duplicate */
duplicate = false;
foreach(cell2, result_spec->listdatums)
{
Const *value2 = lfirst_node(Const, cell2);
Implement table partitioning. Table partitioning is like table inheritance and reuses much of the existing infrastructure, but there are some important differences. The parent is called a partitioned table and is always empty; it may not have indexes or non-inherited constraints, since those make no sense for a relation with no data of its own. The children are called partitions and contain all of the actual data. Each partition has an implicit partitioning constraint. Multiple inheritance is not allowed, and partitioning and inheritance can't be mixed. Partitions can't have extra columns and may not allow nulls unless the parent does. Tuples inserted into the parent are automatically routed to the correct partition, so tuple-routing ON INSERT triggers are not needed. Tuple routing isn't yet supported for partitions which are foreign tables, and it doesn't handle updates that cross partition boundaries. Currently, tables can be range-partitioned or list-partitioned. List partitioning is limited to a single column, but range partitioning can involve multiple columns. A partitioning "column" can be an expression. Because table partitioning is less general than table inheritance, it is hoped that it will be easier to reason about properties of partitions, and therefore that this will serve as a better foundation for a variety of possible optimizations, including query planner optimizations. The tuple routing based which this patch does based on the implicit partitioning constraints is an example of this, but it seems likely that many other useful optimizations are also possible. Amit Langote, reviewed and tested by Robert Haas, Ashutosh Bapat, Amit Kapila, Rajkumar Raghuwanshi, Corey Huinker, Jaime Casanova, Rushabh Lathia, Erik Rijkers, among others. Minor revisions by me.
2016-12-07 19:17:43 +01:00
if (equal(value, value2))
{
duplicate = true;
break;
}
}
if (duplicate)
continue;
result_spec->listdatums = lappend(result_spec->listdatums,
value);
}
}
else if (strategy == PARTITION_STRATEGY_RANGE)
{
if (spec->strategy != PARTITION_STRATEGY_RANGE)
ereport(ERROR,
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
errmsg("invalid bound specification for a range partition"),
Code review focused on new node types added by partitioning support. Fix failure to check that we got a plain Const from const-simplification of a coercion request. This is the cause of bug #14666 from Tian Bing: there is an int4 to money cast, but it's only stable not immutable (because of dependence on lc_monetary), resulting in a FuncExpr that the code was miserably unequipped to deal with, or indeed even to notice that it was failing to deal with. Add test cases around this coercion behavior. In view of the above, sprinkle the code liberally with castNode() macros, in hope of catching the next such bug a bit sooner. Also, change some functions that were randomly declared to take Node* to take more specific pointer types. And change some struct fields that were declared Node* but could be given more specific types, allowing removal of assorted explicit casts. Place PARTITION_MAX_KEYS check a bit closer to the code it's protecting. Likewise check only-one-key-for-list-partitioning restriction in a less random place. Avoid not-per-project-style usages like !strcmp(...). Fix assorted failures to avoid scribbling on the input of parse transformation. I'm not sure how necessary this is, but it's entirely silly for these functions to be expending cycles to avoid that and not getting it right. Add guards against partitioning on system columns. Put backend/nodes/ support code into an order that matches handling of these node types elsewhere. Annotate the fact that somebody added location fields to PartitionBoundSpec and PartitionRangeDatum but forgot to handle them in outfuncs.c/readfuncs.c. This is fairly harmless for production purposes (since readfuncs.c would just substitute -1 anyway) but it's still bogus. It's not worth forcing a post-beta1 initdb just to fix this, but if we have another reason to force initdb before 10.0, we should go back and clean this up. Contrariwise, somebody added location fields to PartitionElem and PartitionSpec but forgot to teach exprLocation() about them. Consolidate duplicative code in transformPartitionBound(). Improve a couple of error messages. Improve assorted commentary. Re-pgindent the files touched by this patch; this affects a few comment blocks that must have been added quite recently. Report: https://postgr.es/m/20170524024550.29935.14396@wrigleys.postgresql.org
2017-05-29 05:20:28 +02:00
parser_errposition(pstate, exprLocation((Node *) spec))));
Implement table partitioning. Table partitioning is like table inheritance and reuses much of the existing infrastructure, but there are some important differences. The parent is called a partitioned table and is always empty; it may not have indexes or non-inherited constraints, since those make no sense for a relation with no data of its own. The children are called partitions and contain all of the actual data. Each partition has an implicit partitioning constraint. Multiple inheritance is not allowed, and partitioning and inheritance can't be mixed. Partitions can't have extra columns and may not allow nulls unless the parent does. Tuples inserted into the parent are automatically routed to the correct partition, so tuple-routing ON INSERT triggers are not needed. Tuple routing isn't yet supported for partitions which are foreign tables, and it doesn't handle updates that cross partition boundaries. Currently, tables can be range-partitioned or list-partitioned. List partitioning is limited to a single column, but range partitioning can involve multiple columns. A partitioning "column" can be an expression. Because table partitioning is less general than table inheritance, it is hoped that it will be easier to reason about properties of partitions, and therefore that this will serve as a better foundation for a variety of possible optimizations, including query planner optimizations. The tuple routing based which this patch does based on the implicit partitioning constraints is an example of this, but it seems likely that many other useful optimizations are also possible. Amit Langote, reviewed and tested by Robert Haas, Ashutosh Bapat, Amit Kapila, Rajkumar Raghuwanshi, Corey Huinker, Jaime Casanova, Rushabh Lathia, Erik Rijkers, among others. Minor revisions by me.
2016-12-07 19:17:43 +01:00
if (list_length(spec->lowerdatums) != partnatts)
ereport(ERROR,
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
errmsg("FROM must specify exactly one value per partitioning column")));
if (list_length(spec->upperdatums) != partnatts)
ereport(ERROR,
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
errmsg("TO must specify exactly one value per partitioning column")));
/*
* Convert raw parse nodes into PartitionRangeDatum nodes and perform
* any necessary validation.
*/
result_spec->lowerdatums =
transformPartitionRangeBounds(pstate, spec->lowerdatums,
parent);
result_spec->upperdatums =
transformPartitionRangeBounds(pstate, spec->upperdatums,
parent);
}
else
elog(ERROR, "unexpected partition strategy: %d", (int) strategy);
return result_spec;
}
/*
* transformPartitionRangeBounds
* This converts the expressions for range partition bounds from the raw
* grammar representation to PartitionRangeDatum structs
*/
static List *
transformPartitionRangeBounds(ParseState *pstate, List *blist,
Relation parent)
{
List *result = NIL;
PartitionKey key = RelationGetPartitionKey(parent);
List *partexprs = get_partition_exprs(key);
ListCell *lc;
int i,
j;
i = j = 0;
foreach(lc, blist)
{
Node *expr = lfirst(lc);
PartitionRangeDatum *prd = NULL;
/*
* Infinite range bounds -- "minvalue" and "maxvalue" -- get passed in
* as ColumnRefs.
*/
if (IsA(expr, ColumnRef))
{
ColumnRef *cref = (ColumnRef *) expr;
char *cname = NULL;
/*
* There should be a single field named either "minvalue" or
* "maxvalue".
*/
if (list_length(cref->fields) == 1 &&
IsA(linitial(cref->fields), String))
cname = strVal(linitial(cref->fields));
if (cname == NULL)
{
/*
* ColumnRef is not in the desired single-field-name form. For
* consistency between all partition strategies, let the
* expression transformation report any errors rather than
* doing it ourselves.
*/
}
else if (strcmp("minvalue", cname) == 0)
{
prd = makeNode(PartitionRangeDatum);
prd->kind = PARTITION_RANGE_DATUM_MINVALUE;
prd->value = NULL;
}
else if (strcmp("maxvalue", cname) == 0)
{
prd = makeNode(PartitionRangeDatum);
prd->kind = PARTITION_RANGE_DATUM_MAXVALUE;
prd->value = NULL;
}
}
if (prd == NULL)
Implement table partitioning. Table partitioning is like table inheritance and reuses much of the existing infrastructure, but there are some important differences. The parent is called a partitioned table and is always empty; it may not have indexes or non-inherited constraints, since those make no sense for a relation with no data of its own. The children are called partitions and contain all of the actual data. Each partition has an implicit partitioning constraint. Multiple inheritance is not allowed, and partitioning and inheritance can't be mixed. Partitions can't have extra columns and may not allow nulls unless the parent does. Tuples inserted into the parent are automatically routed to the correct partition, so tuple-routing ON INSERT triggers are not needed. Tuple routing isn't yet supported for partitions which are foreign tables, and it doesn't handle updates that cross partition boundaries. Currently, tables can be range-partitioned or list-partitioned. List partitioning is limited to a single column, but range partitioning can involve multiple columns. A partitioning "column" can be an expression. Because table partitioning is less general than table inheritance, it is hoped that it will be easier to reason about properties of partitions, and therefore that this will serve as a better foundation for a variety of possible optimizations, including query planner optimizations. The tuple routing based which this patch does based on the implicit partitioning constraints is an example of this, but it seems likely that many other useful optimizations are also possible. Amit Langote, reviewed and tested by Robert Haas, Ashutosh Bapat, Amit Kapila, Rajkumar Raghuwanshi, Corey Huinker, Jaime Casanova, Rushabh Lathia, Erik Rijkers, among others. Minor revisions by me.
2016-12-07 19:17:43 +01:00
{
Code review focused on new node types added by partitioning support. Fix failure to check that we got a plain Const from const-simplification of a coercion request. This is the cause of bug #14666 from Tian Bing: there is an int4 to money cast, but it's only stable not immutable (because of dependence on lc_monetary), resulting in a FuncExpr that the code was miserably unequipped to deal with, or indeed even to notice that it was failing to deal with. Add test cases around this coercion behavior. In view of the above, sprinkle the code liberally with castNode() macros, in hope of catching the next such bug a bit sooner. Also, change some functions that were randomly declared to take Node* to take more specific pointer types. And change some struct fields that were declared Node* but could be given more specific types, allowing removal of assorted explicit casts. Place PARTITION_MAX_KEYS check a bit closer to the code it's protecting. Likewise check only-one-key-for-list-partitioning restriction in a less random place. Avoid not-per-project-style usages like !strcmp(...). Fix assorted failures to avoid scribbling on the input of parse transformation. I'm not sure how necessary this is, but it's entirely silly for these functions to be expending cycles to avoid that and not getting it right. Add guards against partitioning on system columns. Put backend/nodes/ support code into an order that matches handling of these node types elsewhere. Annotate the fact that somebody added location fields to PartitionBoundSpec and PartitionRangeDatum but forgot to handle them in outfuncs.c/readfuncs.c. This is fairly harmless for production purposes (since readfuncs.c would just substitute -1 anyway) but it's still bogus. It's not worth forcing a post-beta1 initdb just to fix this, but if we have another reason to force initdb before 10.0, we should go back and clean this up. Contrariwise, somebody added location fields to PartitionElem and PartitionSpec but forgot to teach exprLocation() about them. Consolidate duplicative code in transformPartitionBound(). Improve a couple of error messages. Improve assorted commentary. Re-pgindent the files touched by this patch; this affects a few comment blocks that must have been added quite recently. Report: https://postgr.es/m/20170524024550.29935.14396@wrigleys.postgresql.org
2017-05-29 05:20:28 +02:00
char *colname;
Oid coltype;
int32 coltypmod;
Oid partcollation;
Code review focused on new node types added by partitioning support. Fix failure to check that we got a plain Const from const-simplification of a coercion request. This is the cause of bug #14666 from Tian Bing: there is an int4 to money cast, but it's only stable not immutable (because of dependence on lc_monetary), resulting in a FuncExpr that the code was miserably unequipped to deal with, or indeed even to notice that it was failing to deal with. Add test cases around this coercion behavior. In view of the above, sprinkle the code liberally with castNode() macros, in hope of catching the next such bug a bit sooner. Also, change some functions that were randomly declared to take Node* to take more specific pointer types. And change some struct fields that were declared Node* but could be given more specific types, allowing removal of assorted explicit casts. Place PARTITION_MAX_KEYS check a bit closer to the code it's protecting. Likewise check only-one-key-for-list-partitioning restriction in a less random place. Avoid not-per-project-style usages like !strcmp(...). Fix assorted failures to avoid scribbling on the input of parse transformation. I'm not sure how necessary this is, but it's entirely silly for these functions to be expending cycles to avoid that and not getting it right. Add guards against partitioning on system columns. Put backend/nodes/ support code into an order that matches handling of these node types elsewhere. Annotate the fact that somebody added location fields to PartitionBoundSpec and PartitionRangeDatum but forgot to handle them in outfuncs.c/readfuncs.c. This is fairly harmless for production purposes (since readfuncs.c would just substitute -1 anyway) but it's still bogus. It's not worth forcing a post-beta1 initdb just to fix this, but if we have another reason to force initdb before 10.0, we should go back and clean this up. Contrariwise, somebody added location fields to PartitionElem and PartitionSpec but forgot to teach exprLocation() about them. Consolidate duplicative code in transformPartitionBound(). Improve a couple of error messages. Improve assorted commentary. Re-pgindent the files touched by this patch; this affects a few comment blocks that must have been added quite recently. Report: https://postgr.es/m/20170524024550.29935.14396@wrigleys.postgresql.org
2017-05-29 05:20:28 +02:00
Const *value;
Implement table partitioning. Table partitioning is like table inheritance and reuses much of the existing infrastructure, but there are some important differences. The parent is called a partitioned table and is always empty; it may not have indexes or non-inherited constraints, since those make no sense for a relation with no data of its own. The children are called partitions and contain all of the actual data. Each partition has an implicit partitioning constraint. Multiple inheritance is not allowed, and partitioning and inheritance can't be mixed. Partitions can't have extra columns and may not allow nulls unless the parent does. Tuples inserted into the parent are automatically routed to the correct partition, so tuple-routing ON INSERT triggers are not needed. Tuple routing isn't yet supported for partitions which are foreign tables, and it doesn't handle updates that cross partition boundaries. Currently, tables can be range-partitioned or list-partitioned. List partitioning is limited to a single column, but range partitioning can involve multiple columns. A partitioning "column" can be an expression. Because table partitioning is less general than table inheritance, it is hoped that it will be easier to reason about properties of partitions, and therefore that this will serve as a better foundation for a variety of possible optimizations, including query planner optimizations. The tuple routing based which this patch does based on the implicit partitioning constraints is an example of this, but it seems likely that many other useful optimizations are also possible. Amit Langote, reviewed and tested by Robert Haas, Ashutosh Bapat, Amit Kapila, Rajkumar Raghuwanshi, Corey Huinker, Jaime Casanova, Rushabh Lathia, Erik Rijkers, among others. Minor revisions by me.
2016-12-07 19:17:43 +01:00
/* Get the column's name in case we need to output an error */
if (key->partattrs[i] != 0)
colname = get_attname(RelationGetRelid(parent),
key->partattrs[i], false);
Implement table partitioning. Table partitioning is like table inheritance and reuses much of the existing infrastructure, but there are some important differences. The parent is called a partitioned table and is always empty; it may not have indexes or non-inherited constraints, since those make no sense for a relation with no data of its own. The children are called partitions and contain all of the actual data. Each partition has an implicit partitioning constraint. Multiple inheritance is not allowed, and partitioning and inheritance can't be mixed. Partitions can't have extra columns and may not allow nulls unless the parent does. Tuples inserted into the parent are automatically routed to the correct partition, so tuple-routing ON INSERT triggers are not needed. Tuple routing isn't yet supported for partitions which are foreign tables, and it doesn't handle updates that cross partition boundaries. Currently, tables can be range-partitioned or list-partitioned. List partitioning is limited to a single column, but range partitioning can involve multiple columns. A partitioning "column" can be an expression. Because table partitioning is less general than table inheritance, it is hoped that it will be easier to reason about properties of partitions, and therefore that this will serve as a better foundation for a variety of possible optimizations, including query planner optimizations. The tuple routing based which this patch does based on the implicit partitioning constraints is an example of this, but it seems likely that many other useful optimizations are also possible. Amit Langote, reviewed and tested by Robert Haas, Ashutosh Bapat, Amit Kapila, Rajkumar Raghuwanshi, Corey Huinker, Jaime Casanova, Rushabh Lathia, Erik Rijkers, among others. Minor revisions by me.
2016-12-07 19:17:43 +01:00
else
{
colname = deparse_expression((Node *) list_nth(partexprs, j),
deparse_context_for(RelationGetRelationName(parent),
RelationGetRelid(parent)),
false, false);
++j;
}
Code review focused on new node types added by partitioning support. Fix failure to check that we got a plain Const from const-simplification of a coercion request. This is the cause of bug #14666 from Tian Bing: there is an int4 to money cast, but it's only stable not immutable (because of dependence on lc_monetary), resulting in a FuncExpr that the code was miserably unequipped to deal with, or indeed even to notice that it was failing to deal with. Add test cases around this coercion behavior. In view of the above, sprinkle the code liberally with castNode() macros, in hope of catching the next such bug a bit sooner. Also, change some functions that were randomly declared to take Node* to take more specific pointer types. And change some struct fields that were declared Node* but could be given more specific types, allowing removal of assorted explicit casts. Place PARTITION_MAX_KEYS check a bit closer to the code it's protecting. Likewise check only-one-key-for-list-partitioning restriction in a less random place. Avoid not-per-project-style usages like !strcmp(...). Fix assorted failures to avoid scribbling on the input of parse transformation. I'm not sure how necessary this is, but it's entirely silly for these functions to be expending cycles to avoid that and not getting it right. Add guards against partitioning on system columns. Put backend/nodes/ support code into an order that matches handling of these node types elsewhere. Annotate the fact that somebody added location fields to PartitionBoundSpec and PartitionRangeDatum but forgot to handle them in outfuncs.c/readfuncs.c. This is fairly harmless for production purposes (since readfuncs.c would just substitute -1 anyway) but it's still bogus. It's not worth forcing a post-beta1 initdb just to fix this, but if we have another reason to force initdb before 10.0, we should go back and clean this up. Contrariwise, somebody added location fields to PartitionElem and PartitionSpec but forgot to teach exprLocation() about them. Consolidate duplicative code in transformPartitionBound(). Improve a couple of error messages. Improve assorted commentary. Re-pgindent the files touched by this patch; this affects a few comment blocks that must have been added quite recently. Report: https://postgr.es/m/20170524024550.29935.14396@wrigleys.postgresql.org
2017-05-29 05:20:28 +02:00
/* Need its type data too */
coltype = get_partition_col_typid(key, i);
coltypmod = get_partition_col_typmod(key, i);
partcollation = get_partition_col_collation(key, i);
Implement table partitioning. Table partitioning is like table inheritance and reuses much of the existing infrastructure, but there are some important differences. The parent is called a partitioned table and is always empty; it may not have indexes or non-inherited constraints, since those make no sense for a relation with no data of its own. The children are called partitions and contain all of the actual data. Each partition has an implicit partitioning constraint. Multiple inheritance is not allowed, and partitioning and inheritance can't be mixed. Partitions can't have extra columns and may not allow nulls unless the parent does. Tuples inserted into the parent are automatically routed to the correct partition, so tuple-routing ON INSERT triggers are not needed. Tuple routing isn't yet supported for partitions which are foreign tables, and it doesn't handle updates that cross partition boundaries. Currently, tables can be range-partitioned or list-partitioned. List partitioning is limited to a single column, but range partitioning can involve multiple columns. A partitioning "column" can be an expression. Because table partitioning is less general than table inheritance, it is hoped that it will be easier to reason about properties of partitions, and therefore that this will serve as a better foundation for a variety of possible optimizations, including query planner optimizations. The tuple routing based which this patch does based on the implicit partitioning constraints is an example of this, but it seems likely that many other useful optimizations are also possible. Amit Langote, reviewed and tested by Robert Haas, Ashutosh Bapat, Amit Kapila, Rajkumar Raghuwanshi, Corey Huinker, Jaime Casanova, Rushabh Lathia, Erik Rijkers, among others. Minor revisions by me.
2016-12-07 19:17:43 +01:00
value = transformPartitionBoundValue(pstate, expr,
colname,
coltype, coltypmod,
partcollation);
if (value->constisnull)
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("cannot specify NULL in range bound")));
prd = makeNode(PartitionRangeDatum);
prd->kind = PARTITION_RANGE_DATUM_VALUE;
prd->value = (Node *) value;
Implement table partitioning. Table partitioning is like table inheritance and reuses much of the existing infrastructure, but there are some important differences. The parent is called a partitioned table and is always empty; it may not have indexes or non-inherited constraints, since those make no sense for a relation with no data of its own. The children are called partitions and contain all of the actual data. Each partition has an implicit partitioning constraint. Multiple inheritance is not allowed, and partitioning and inheritance can't be mixed. Partitions can't have extra columns and may not allow nulls unless the parent does. Tuples inserted into the parent are automatically routed to the correct partition, so tuple-routing ON INSERT triggers are not needed. Tuple routing isn't yet supported for partitions which are foreign tables, and it doesn't handle updates that cross partition boundaries. Currently, tables can be range-partitioned or list-partitioned. List partitioning is limited to a single column, but range partitioning can involve multiple columns. A partitioning "column" can be an expression. Because table partitioning is less general than table inheritance, it is hoped that it will be easier to reason about properties of partitions, and therefore that this will serve as a better foundation for a variety of possible optimizations, including query planner optimizations. The tuple routing based which this patch does based on the implicit partitioning constraints is an example of this, but it seems likely that many other useful optimizations are also possible. Amit Langote, reviewed and tested by Robert Haas, Ashutosh Bapat, Amit Kapila, Rajkumar Raghuwanshi, Corey Huinker, Jaime Casanova, Rushabh Lathia, Erik Rijkers, among others. Minor revisions by me.
2016-12-07 19:17:43 +01:00
++i;
}
prd->location = exprLocation(expr);
result = lappend(result, prd);
Implement table partitioning. Table partitioning is like table inheritance and reuses much of the existing infrastructure, but there are some important differences. The parent is called a partitioned table and is always empty; it may not have indexes or non-inherited constraints, since those make no sense for a relation with no data of its own. The children are called partitions and contain all of the actual data. Each partition has an implicit partitioning constraint. Multiple inheritance is not allowed, and partitioning and inheritance can't be mixed. Partitions can't have extra columns and may not allow nulls unless the parent does. Tuples inserted into the parent are automatically routed to the correct partition, so tuple-routing ON INSERT triggers are not needed. Tuple routing isn't yet supported for partitions which are foreign tables, and it doesn't handle updates that cross partition boundaries. Currently, tables can be range-partitioned or list-partitioned. List partitioning is limited to a single column, but range partitioning can involve multiple columns. A partitioning "column" can be an expression. Because table partitioning is less general than table inheritance, it is hoped that it will be easier to reason about properties of partitions, and therefore that this will serve as a better foundation for a variety of possible optimizations, including query planner optimizations. The tuple routing based which this patch does based on the implicit partitioning constraints is an example of this, but it seems likely that many other useful optimizations are also possible. Amit Langote, reviewed and tested by Robert Haas, Ashutosh Bapat, Amit Kapila, Rajkumar Raghuwanshi, Corey Huinker, Jaime Casanova, Rushabh Lathia, Erik Rijkers, among others. Minor revisions by me.
2016-12-07 19:17:43 +01:00
}
/*
* Once we see MINVALUE or MAXVALUE for one column, the remaining columns
* must be the same.
*/
validateInfiniteBounds(pstate, result);
return result;
Code review focused on new node types added by partitioning support. Fix failure to check that we got a plain Const from const-simplification of a coercion request. This is the cause of bug #14666 from Tian Bing: there is an int4 to money cast, but it's only stable not immutable (because of dependence on lc_monetary), resulting in a FuncExpr that the code was miserably unequipped to deal with, or indeed even to notice that it was failing to deal with. Add test cases around this coercion behavior. In view of the above, sprinkle the code liberally with castNode() macros, in hope of catching the next such bug a bit sooner. Also, change some functions that were randomly declared to take Node* to take more specific pointer types. And change some struct fields that were declared Node* but could be given more specific types, allowing removal of assorted explicit casts. Place PARTITION_MAX_KEYS check a bit closer to the code it's protecting. Likewise check only-one-key-for-list-partitioning restriction in a less random place. Avoid not-per-project-style usages like !strcmp(...). Fix assorted failures to avoid scribbling on the input of parse transformation. I'm not sure how necessary this is, but it's entirely silly for these functions to be expending cycles to avoid that and not getting it right. Add guards against partitioning on system columns. Put backend/nodes/ support code into an order that matches handling of these node types elsewhere. Annotate the fact that somebody added location fields to PartitionBoundSpec and PartitionRangeDatum but forgot to handle them in outfuncs.c/readfuncs.c. This is fairly harmless for production purposes (since readfuncs.c would just substitute -1 anyway) but it's still bogus. It's not worth forcing a post-beta1 initdb just to fix this, but if we have another reason to force initdb before 10.0, we should go back and clean this up. Contrariwise, somebody added location fields to PartitionElem and PartitionSpec but forgot to teach exprLocation() about them. Consolidate duplicative code in transformPartitionBound(). Improve a couple of error messages. Improve assorted commentary. Re-pgindent the files touched by this patch; this affects a few comment blocks that must have been added quite recently. Report: https://postgr.es/m/20170524024550.29935.14396@wrigleys.postgresql.org
2017-05-29 05:20:28 +02:00
}
/*
* validateInfiniteBounds
*
* Check that a MAXVALUE or MINVALUE specification in a partition bound is
* followed only by more of the same.
*/
static void
validateInfiniteBounds(ParseState *pstate, List *blist)
{
ListCell *lc;
PartitionRangeDatumKind kind = PARTITION_RANGE_DATUM_VALUE;
foreach(lc, blist)
{
PartitionRangeDatum *prd = lfirst_node(PartitionRangeDatum, lc);
if (kind == prd->kind)
continue;
switch (kind)
{
case PARTITION_RANGE_DATUM_VALUE:
kind = prd->kind;
break;
case PARTITION_RANGE_DATUM_MAXVALUE:
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
errmsg("every bound following MAXVALUE must also be MAXVALUE"),
parser_errposition(pstate, exprLocation((Node *) prd))));
break;
case PARTITION_RANGE_DATUM_MINVALUE:
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
errmsg("every bound following MINVALUE must also be MINVALUE"),
parser_errposition(pstate, exprLocation((Node *) prd))));
break;
}
}
}
Code review focused on new node types added by partitioning support. Fix failure to check that we got a plain Const from const-simplification of a coercion request. This is the cause of bug #14666 from Tian Bing: there is an int4 to money cast, but it's only stable not immutable (because of dependence on lc_monetary), resulting in a FuncExpr that the code was miserably unequipped to deal with, or indeed even to notice that it was failing to deal with. Add test cases around this coercion behavior. In view of the above, sprinkle the code liberally with castNode() macros, in hope of catching the next such bug a bit sooner. Also, change some functions that were randomly declared to take Node* to take more specific pointer types. And change some struct fields that were declared Node* but could be given more specific types, allowing removal of assorted explicit casts. Place PARTITION_MAX_KEYS check a bit closer to the code it's protecting. Likewise check only-one-key-for-list-partitioning restriction in a less random place. Avoid not-per-project-style usages like !strcmp(...). Fix assorted failures to avoid scribbling on the input of parse transformation. I'm not sure how necessary this is, but it's entirely silly for these functions to be expending cycles to avoid that and not getting it right. Add guards against partitioning on system columns. Put backend/nodes/ support code into an order that matches handling of these node types elsewhere. Annotate the fact that somebody added location fields to PartitionBoundSpec and PartitionRangeDatum but forgot to handle them in outfuncs.c/readfuncs.c. This is fairly harmless for production purposes (since readfuncs.c would just substitute -1 anyway) but it's still bogus. It's not worth forcing a post-beta1 initdb just to fix this, but if we have another reason to force initdb before 10.0, we should go back and clean this up. Contrariwise, somebody added location fields to PartitionElem and PartitionSpec but forgot to teach exprLocation() about them. Consolidate duplicative code in transformPartitionBound(). Improve a couple of error messages. Improve assorted commentary. Re-pgindent the files touched by this patch; this affects a few comment blocks that must have been added quite recently. Report: https://postgr.es/m/20170524024550.29935.14396@wrigleys.postgresql.org
2017-05-29 05:20:28 +02:00
/*
* Transform one entry in a partition bound spec, producing a constant.
Code review focused on new node types added by partitioning support. Fix failure to check that we got a plain Const from const-simplification of a coercion request. This is the cause of bug #14666 from Tian Bing: there is an int4 to money cast, but it's only stable not immutable (because of dependence on lc_monetary), resulting in a FuncExpr that the code was miserably unequipped to deal with, or indeed even to notice that it was failing to deal with. Add test cases around this coercion behavior. In view of the above, sprinkle the code liberally with castNode() macros, in hope of catching the next such bug a bit sooner. Also, change some functions that were randomly declared to take Node* to take more specific pointer types. And change some struct fields that were declared Node* but could be given more specific types, allowing removal of assorted explicit casts. Place PARTITION_MAX_KEYS check a bit closer to the code it's protecting. Likewise check only-one-key-for-list-partitioning restriction in a less random place. Avoid not-per-project-style usages like !strcmp(...). Fix assorted failures to avoid scribbling on the input of parse transformation. I'm not sure how necessary this is, but it's entirely silly for these functions to be expending cycles to avoid that and not getting it right. Add guards against partitioning on system columns. Put backend/nodes/ support code into an order that matches handling of these node types elsewhere. Annotate the fact that somebody added location fields to PartitionBoundSpec and PartitionRangeDatum but forgot to handle them in outfuncs.c/readfuncs.c. This is fairly harmless for production purposes (since readfuncs.c would just substitute -1 anyway) but it's still bogus. It's not worth forcing a post-beta1 initdb just to fix this, but if we have another reason to force initdb before 10.0, we should go back and clean this up. Contrariwise, somebody added location fields to PartitionElem and PartitionSpec but forgot to teach exprLocation() about them. Consolidate duplicative code in transformPartitionBound(). Improve a couple of error messages. Improve assorted commentary. Re-pgindent the files touched by this patch; this affects a few comment blocks that must have been added quite recently. Report: https://postgr.es/m/20170524024550.29935.14396@wrigleys.postgresql.org
2017-05-29 05:20:28 +02:00
*/
static Const *
transformPartitionBoundValue(ParseState *pstate, Node *val,
const char *colName, Oid colType, int32 colTypmod,
Oid partCollation)
Code review focused on new node types added by partitioning support. Fix failure to check that we got a plain Const from const-simplification of a coercion request. This is the cause of bug #14666 from Tian Bing: there is an int4 to money cast, but it's only stable not immutable (because of dependence on lc_monetary), resulting in a FuncExpr that the code was miserably unequipped to deal with, or indeed even to notice that it was failing to deal with. Add test cases around this coercion behavior. In view of the above, sprinkle the code liberally with castNode() macros, in hope of catching the next such bug a bit sooner. Also, change some functions that were randomly declared to take Node* to take more specific pointer types. And change some struct fields that were declared Node* but could be given more specific types, allowing removal of assorted explicit casts. Place PARTITION_MAX_KEYS check a bit closer to the code it's protecting. Likewise check only-one-key-for-list-partitioning restriction in a less random place. Avoid not-per-project-style usages like !strcmp(...). Fix assorted failures to avoid scribbling on the input of parse transformation. I'm not sure how necessary this is, but it's entirely silly for these functions to be expending cycles to avoid that and not getting it right. Add guards against partitioning on system columns. Put backend/nodes/ support code into an order that matches handling of these node types elsewhere. Annotate the fact that somebody added location fields to PartitionBoundSpec and PartitionRangeDatum but forgot to handle them in outfuncs.c/readfuncs.c. This is fairly harmless for production purposes (since readfuncs.c would just substitute -1 anyway) but it's still bogus. It's not worth forcing a post-beta1 initdb just to fix this, but if we have another reason to force initdb before 10.0, we should go back and clean this up. Contrariwise, somebody added location fields to PartitionElem and PartitionSpec but forgot to teach exprLocation() about them. Consolidate duplicative code in transformPartitionBound(). Improve a couple of error messages. Improve assorted commentary. Re-pgindent the files touched by this patch; this affects a few comment blocks that must have been added quite recently. Report: https://postgr.es/m/20170524024550.29935.14396@wrigleys.postgresql.org
2017-05-29 05:20:28 +02:00
{
Node *value;
/* Transform raw parsetree */
value = transformExpr(pstate, val, EXPR_KIND_PARTITION_BOUND);
/*
* transformExpr() should have already rejected column references,
* subqueries, aggregates, window functions, and SRFs, based on the
* EXPR_KIND_ of a partition bound expression.
*/
Assert(!contain_var_clause(value));
/*
* Coerce to the correct type. This might cause an explicit coercion step
* to be added on top of the expression, which must be evaluated before
* returning the result to the caller.
*/
Code review focused on new node types added by partitioning support. Fix failure to check that we got a plain Const from const-simplification of a coercion request. This is the cause of bug #14666 from Tian Bing: there is an int4 to money cast, but it's only stable not immutable (because of dependence on lc_monetary), resulting in a FuncExpr that the code was miserably unequipped to deal with, or indeed even to notice that it was failing to deal with. Add test cases around this coercion behavior. In view of the above, sprinkle the code liberally with castNode() macros, in hope of catching the next such bug a bit sooner. Also, change some functions that were randomly declared to take Node* to take more specific pointer types. And change some struct fields that were declared Node* but could be given more specific types, allowing removal of assorted explicit casts. Place PARTITION_MAX_KEYS check a bit closer to the code it's protecting. Likewise check only-one-key-for-list-partitioning restriction in a less random place. Avoid not-per-project-style usages like !strcmp(...). Fix assorted failures to avoid scribbling on the input of parse transformation. I'm not sure how necessary this is, but it's entirely silly for these functions to be expending cycles to avoid that and not getting it right. Add guards against partitioning on system columns. Put backend/nodes/ support code into an order that matches handling of these node types elsewhere. Annotate the fact that somebody added location fields to PartitionBoundSpec and PartitionRangeDatum but forgot to handle them in outfuncs.c/readfuncs.c. This is fairly harmless for production purposes (since readfuncs.c would just substitute -1 anyway) but it's still bogus. It's not worth forcing a post-beta1 initdb just to fix this, but if we have another reason to force initdb before 10.0, we should go back and clean this up. Contrariwise, somebody added location fields to PartitionElem and PartitionSpec but forgot to teach exprLocation() about them. Consolidate duplicative code in transformPartitionBound(). Improve a couple of error messages. Improve assorted commentary. Re-pgindent the files touched by this patch; this affects a few comment blocks that must have been added quite recently. Report: https://postgr.es/m/20170524024550.29935.14396@wrigleys.postgresql.org
2017-05-29 05:20:28 +02:00
value = coerce_to_target_type(pstate,
value, exprType(value),
colType,
colTypmod,
COERCION_ASSIGNMENT,
COERCE_IMPLICIT_CAST,
-1);
if (value == NULL)
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
errmsg("specified value cannot be cast to type %s for column \"%s\"",
format_type_be(colType), colName),
parser_errposition(pstate, exprLocation(val))));
Code review focused on new node types added by partitioning support. Fix failure to check that we got a plain Const from const-simplification of a coercion request. This is the cause of bug #14666 from Tian Bing: there is an int4 to money cast, but it's only stable not immutable (because of dependence on lc_monetary), resulting in a FuncExpr that the code was miserably unequipped to deal with, or indeed even to notice that it was failing to deal with. Add test cases around this coercion behavior. In view of the above, sprinkle the code liberally with castNode() macros, in hope of catching the next such bug a bit sooner. Also, change some functions that were randomly declared to take Node* to take more specific pointer types. And change some struct fields that were declared Node* but could be given more specific types, allowing removal of assorted explicit casts. Place PARTITION_MAX_KEYS check a bit closer to the code it's protecting. Likewise check only-one-key-for-list-partitioning restriction in a less random place. Avoid not-per-project-style usages like !strcmp(...). Fix assorted failures to avoid scribbling on the input of parse transformation. I'm not sure how necessary this is, but it's entirely silly for these functions to be expending cycles to avoid that and not getting it right. Add guards against partitioning on system columns. Put backend/nodes/ support code into an order that matches handling of these node types elsewhere. Annotate the fact that somebody added location fields to PartitionBoundSpec and PartitionRangeDatum but forgot to handle them in outfuncs.c/readfuncs.c. This is fairly harmless for production purposes (since readfuncs.c would just substitute -1 anyway) but it's still bogus. It's not worth forcing a post-beta1 initdb just to fix this, but if we have another reason to force initdb before 10.0, we should go back and clean this up. Contrariwise, somebody added location fields to PartitionElem and PartitionSpec but forgot to teach exprLocation() about them. Consolidate duplicative code in transformPartitionBound(). Improve a couple of error messages. Improve assorted commentary. Re-pgindent the files touched by this patch; this affects a few comment blocks that must have been added quite recently. Report: https://postgr.es/m/20170524024550.29935.14396@wrigleys.postgresql.org
2017-05-29 05:20:28 +02:00
/*
* Evaluate the expression, if needed, assigning the partition key's data
* type and collation to the resulting Const node.
*/
if (!IsA(value, Const))
{
assign_expr_collations(pstate, value);
value = (Node *) expression_planner((Expr *) value);
value = (Node *) evaluate_expr((Expr *) value, colType, colTypmod,
partCollation);
if (!IsA(value, Const))
elog(ERROR, "could not evaluate partition bound expression");
}
else
{
/*
* If the expression is already a Const, as is often the case, we can
* skip the rather expensive steps above. But we still have to insert
* the right collation, since coerce_to_target_type doesn't handle
* that.
*/
((Const *) value)->constcollid = partCollation;
}
/*
* Attach original expression's parse location to the Const, so that
* that's what will be reported for any later errors related to this
* partition bound.
*/
((Const *) value)->location = exprLocation(val);
Code review focused on new node types added by partitioning support. Fix failure to check that we got a plain Const from const-simplification of a coercion request. This is the cause of bug #14666 from Tian Bing: there is an int4 to money cast, but it's only stable not immutable (because of dependence on lc_monetary), resulting in a FuncExpr that the code was miserably unequipped to deal with, or indeed even to notice that it was failing to deal with. Add test cases around this coercion behavior. In view of the above, sprinkle the code liberally with castNode() macros, in hope of catching the next such bug a bit sooner. Also, change some functions that were randomly declared to take Node* to take more specific pointer types. And change some struct fields that were declared Node* but could be given more specific types, allowing removal of assorted explicit casts. Place PARTITION_MAX_KEYS check a bit closer to the code it's protecting. Likewise check only-one-key-for-list-partitioning restriction in a less random place. Avoid not-per-project-style usages like !strcmp(...). Fix assorted failures to avoid scribbling on the input of parse transformation. I'm not sure how necessary this is, but it's entirely silly for these functions to be expending cycles to avoid that and not getting it right. Add guards against partitioning on system columns. Put backend/nodes/ support code into an order that matches handling of these node types elsewhere. Annotate the fact that somebody added location fields to PartitionBoundSpec and PartitionRangeDatum but forgot to handle them in outfuncs.c/readfuncs.c. This is fairly harmless for production purposes (since readfuncs.c would just substitute -1 anyway) but it's still bogus. It's not worth forcing a post-beta1 initdb just to fix this, but if we have another reason to force initdb before 10.0, we should go back and clean this up. Contrariwise, somebody added location fields to PartitionElem and PartitionSpec but forgot to teach exprLocation() about them. Consolidate duplicative code in transformPartitionBound(). Improve a couple of error messages. Improve assorted commentary. Re-pgindent the files touched by this patch; this affects a few comment blocks that must have been added quite recently. Report: https://postgr.es/m/20170524024550.29935.14396@wrigleys.postgresql.org
2017-05-29 05:20:28 +02:00
return (Const *) value;
Implement table partitioning. Table partitioning is like table inheritance and reuses much of the existing infrastructure, but there are some important differences. The parent is called a partitioned table and is always empty; it may not have indexes or non-inherited constraints, since those make no sense for a relation with no data of its own. The children are called partitions and contain all of the actual data. Each partition has an implicit partitioning constraint. Multiple inheritance is not allowed, and partitioning and inheritance can't be mixed. Partitions can't have extra columns and may not allow nulls unless the parent does. Tuples inserted into the parent are automatically routed to the correct partition, so tuple-routing ON INSERT triggers are not needed. Tuple routing isn't yet supported for partitions which are foreign tables, and it doesn't handle updates that cross partition boundaries. Currently, tables can be range-partitioned or list-partitioned. List partitioning is limited to a single column, but range partitioning can involve multiple columns. A partitioning "column" can be an expression. Because table partitioning is less general than table inheritance, it is hoped that it will be easier to reason about properties of partitions, and therefore that this will serve as a better foundation for a variety of possible optimizations, including query planner optimizations. The tuple routing based which this patch does based on the implicit partitioning constraints is an example of this, but it seems likely that many other useful optimizations are also possible. Amit Langote, reviewed and tested by Robert Haas, Ashutosh Bapat, Amit Kapila, Rajkumar Raghuwanshi, Corey Huinker, Jaime Casanova, Rushabh Lathia, Erik Rijkers, among others. Minor revisions by me.
2016-12-07 19:17:43 +01:00
}