postgresql/src/backend/commands/tablecmds.c

10540 lines
316 KiB
C
Raw Normal View History

/*-------------------------------------------------------------------------
*
* tablecmds.c
* Commands for creating and altering table structures and settings
*
* Portions Copyright (c) 1996-2013, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
*
* IDENTIFICATION
2010-09-20 22:08:53 +02:00
* src/backend/commands/tablecmds.c
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include "access/genam.h"
Improve concurrency of foreign key locking This patch introduces two additional lock modes for tuples: "SELECT FOR KEY SHARE" and "SELECT FOR NO KEY UPDATE". These don't block each other, in contrast with already existing "SELECT FOR SHARE" and "SELECT FOR UPDATE". UPDATE commands that do not modify the values stored in the columns that are part of the key of the tuple now grab a SELECT FOR NO KEY UPDATE lock on the tuple, allowing them to proceed concurrently with tuple locks of the FOR KEY SHARE variety. Foreign key triggers now use FOR KEY SHARE instead of FOR SHARE; this means the concurrency improvement applies to them, which is the whole point of this patch. The added tuple lock semantics require some rejiggering of the multixact module, so that the locking level that each transaction is holding can be stored alongside its Xid. Also, multixacts now need to persist across server restarts and crashes, because they can now represent not only tuple locks, but also tuple updates. This means we need more careful tracking of lifetime of pg_multixact SLRU files; since they now persist longer, we require more infrastructure to figure out when they can be removed. pg_upgrade also needs to be careful to copy pg_multixact files over from the old server to the new, or at least part of multixact.c state, depending on the versions of the old and new servers. Tuple time qualification rules (HeapTupleSatisfies routines) need to be careful not to consider tuples with the "is multi" infomask bit set as being only locked; they might need to look up MultiXact values (i.e. possibly do pg_multixact I/O) to find out the Xid that updated a tuple, whereas they previously were assured to only use information readily available from the tuple header. This is considered acceptable, because the extra I/O would involve cases that would previously cause some commands to block waiting for concurrent transactions to finish. Another important change is the fact that locking tuples that have previously been updated causes the future versions to be marked as locked, too; this is essential for correctness of foreign key checks. This causes additional WAL-logging, also (there was previously a single WAL record for a locked tuple; now there are as many as updated copies of the tuple there exist.) With all this in place, contention related to tuples being checked by foreign key rules should be much reduced. As a bonus, the old behavior that a subtransaction grabbing a stronger tuple lock than the parent (sub)transaction held on a given tuple and later aborting caused the weaker lock to be lost, has been fixed. Many new spec files were added for isolation tester framework, to ensure overall behavior is sane. There's probably room for several more tests. There were several reviewers of this patch; in particular, Noah Misch and Andres Freund spent considerable time in it. Original idea for the patch came from Simon Riggs, after a problem report by Joel Jacobson. Most code is from me, with contributions from Marti Raudsepp, Alexander Shulgin, Noah Misch and Andres Freund. This patch was discussed in several pgsql-hackers threads; the most important start at the following message-ids: AANLkTimo9XVcEzfiBR-ut3KVNDkjm2Vxh+t8kAmWjPuv@mail.gmail.com 1290721684-sup-3951@alvh.no-ip.org 1294953201-sup-2099@alvh.no-ip.org 1320343602-sup-2290@alvh.no-ip.org 1339690386-sup-8927@alvh.no-ip.org 4FE5FF020200002500048A3D@gw.wicourts.gov 4FEAB90A0200002500048B7D@gw.wicourts.gov
2013-01-23 16:04:59 +01:00
#include "access/heapam.h"
#include "access/heapam_xlog.h"
Improve concurrency of foreign key locking This patch introduces two additional lock modes for tuples: "SELECT FOR KEY SHARE" and "SELECT FOR NO KEY UPDATE". These don't block each other, in contrast with already existing "SELECT FOR SHARE" and "SELECT FOR UPDATE". UPDATE commands that do not modify the values stored in the columns that are part of the key of the tuple now grab a SELECT FOR NO KEY UPDATE lock on the tuple, allowing them to proceed concurrently with tuple locks of the FOR KEY SHARE variety. Foreign key triggers now use FOR KEY SHARE instead of FOR SHARE; this means the concurrency improvement applies to them, which is the whole point of this patch. The added tuple lock semantics require some rejiggering of the multixact module, so that the locking level that each transaction is holding can be stored alongside its Xid. Also, multixacts now need to persist across server restarts and crashes, because they can now represent not only tuple locks, but also tuple updates. This means we need more careful tracking of lifetime of pg_multixact SLRU files; since they now persist longer, we require more infrastructure to figure out when they can be removed. pg_upgrade also needs to be careful to copy pg_multixact files over from the old server to the new, or at least part of multixact.c state, depending on the versions of the old and new servers. Tuple time qualification rules (HeapTupleSatisfies routines) need to be careful not to consider tuples with the "is multi" infomask bit set as being only locked; they might need to look up MultiXact values (i.e. possibly do pg_multixact I/O) to find out the Xid that updated a tuple, whereas they previously were assured to only use information readily available from the tuple header. This is considered acceptable, because the extra I/O would involve cases that would previously cause some commands to block waiting for concurrent transactions to finish. Another important change is the fact that locking tuples that have previously been updated causes the future versions to be marked as locked, too; this is essential for correctness of foreign key checks. This causes additional WAL-logging, also (there was previously a single WAL record for a locked tuple; now there are as many as updated copies of the tuple there exist.) With all this in place, contention related to tuples being checked by foreign key rules should be much reduced. As a bonus, the old behavior that a subtransaction grabbing a stronger tuple lock than the parent (sub)transaction held on a given tuple and later aborting caused the weaker lock to be lost, has been fixed. Many new spec files were added for isolation tester framework, to ensure overall behavior is sane. There's probably room for several more tests. There were several reviewers of this patch; in particular, Noah Misch and Andres Freund spent considerable time in it. Original idea for the patch came from Simon Riggs, after a problem report by Joel Jacobson. Most code is from me, with contributions from Marti Raudsepp, Alexander Shulgin, Noah Misch and Andres Freund. This patch was discussed in several pgsql-hackers threads; the most important start at the following message-ids: AANLkTimo9XVcEzfiBR-ut3KVNDkjm2Vxh+t8kAmWjPuv@mail.gmail.com 1290721684-sup-3951@alvh.no-ip.org 1294953201-sup-2099@alvh.no-ip.org 1320343602-sup-2290@alvh.no-ip.org 1339690386-sup-8927@alvh.no-ip.org 4FE5FF020200002500048A3D@gw.wicourts.gov 4FEAB90A0200002500048B7D@gw.wicourts.gov
2013-01-23 16:04:59 +01:00
#include "access/multixact.h"
#include "access/reloptions.h"
#include "access/relscan.h"
#include "access/sysattr.h"
#include "access/xact.h"
#include "catalog/catalog.h"
#include "catalog/dependency.h"
#include "catalog/heap.h"
#include "catalog/index.h"
1999-07-16 07:00:38 +02:00
#include "catalog/indexing.h"
#include "catalog/namespace.h"
#include "catalog/objectaccess.h"
#include "catalog/pg_collation.h"
#include "catalog/pg_constraint.h"
#include "catalog/pg_depend.h"
#include "catalog/pg_foreign_table.h"
#include "catalog/pg_inherits.h"
#include "catalog/pg_inherits_fn.h"
#include "catalog/pg_namespace.h"
#include "catalog/pg_opclass.h"
#include "catalog/pg_tablespace.h"
#include "catalog/pg_trigger.h"
#include "catalog/pg_type.h"
#include "catalog/pg_type_fn.h"
#include "catalog/storage.h"
#include "catalog/toasting.h"
2002-11-23 05:05:52 +01:00
#include "commands/cluster.h"
#include "commands/comment.h"
#include "commands/defrem.h"
#include "commands/sequence.h"
#include "commands/tablecmds.h"
#include "commands/tablespace.h"
#include "commands/trigger.h"
#include "commands/typecmds.h"
#include "common/relpath.h"
#include "executor/executor.h"
#include "foreign/foreign.h"
1999-07-16 07:00:38 +02:00
#include "miscadmin.h"
#include "nodes/makefuncs.h"
#include "nodes/nodeFuncs.h"
#include "nodes/parsenodes.h"
#include "optimizer/clauses.h"
#include "optimizer/planner.h"
#include "parser/parse_clause.h"
#include "parser/parse_coerce.h"
#include "parser/parse_collate.h"
#include "parser/parse_expr.h"
#include "parser/parse_oper.h"
#include "parser/parse_relation.h"
#include "parser/parse_type.h"
#include "parser/parse_utilcmd.h"
#include "parser/parser.h"
Changes pg_trigger and extend pg_rewrite in order to allow triggers and rules to be defined with different, per session controllable, behaviors for replication purposes. This will allow replication systems like Slony-I and, as has been stated on pgsql-hackers, other products to control the firing mechanism of triggers and rewrite rules without modifying the system catalog directly. The firing mechanisms are controlled by a new superuser-only GUC variable, session_replication_role, together with a change to pg_trigger.tgenabled and a new column pg_rewrite.ev_enabled. Both columns are a single char data type now (tgenabled was a bool before). The possible values in these attributes are: 'O' - Trigger/Rule fires when session_replication_role is "origin" (default) or "local". This is the default behavior. 'D' - Trigger/Rule is disabled and fires never 'A' - Trigger/Rule fires always regardless of the setting of session_replication_role 'R' - Trigger/Rule fires when session_replication_role is "replica" The GUC variable can only be changed as long as the system does not have any cached query plans. This will prevent changing the session role and accidentally executing stored procedures or functions that have plans cached that expand to the wrong query set due to differences in the rule firing semantics. The SQL syntax for changing a triggers/rules firing semantics is ALTER TABLE <tabname> <when> TRIGGER|RULE <name>; <when> ::= ENABLE | ENABLE ALWAYS | ENABLE REPLICA | DISABLE psql's \d command as well as pg_dump are extended in a backward compatible fashion. Jan
2007-03-20 00:38:32 +01:00
#include "rewrite/rewriteDefine.h"
#include "rewrite/rewriteHandler.h"
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
#include "rewrite/rewriteManip.h"
#include "storage/bufmgr.h"
#include "storage/lmgr.h"
#include "storage/lock.h"
#include "storage/predicate.h"
#include "storage/smgr.h"
#include "utils/acl.h"
#include "utils/builtins.h"
#include "utils/fmgroids.h"
#include "utils/inval.h"
#include "utils/lsyscache.h"
#include "utils/memutils.h"
#include "utils/relcache.h"
#include "utils/snapmgr.h"
#include "utils/syscache.h"
#include "utils/tqual.h"
#include "utils/typcache.h"
/*
* ON COMMIT action list
*/
typedef struct OnCommitItem
{
2003-08-04 02:43:34 +02:00
Oid relid; /* relid of relation */
OnCommitAction oncommit; /* what to do at end of xact */
/*
* If this entry was created during the current transaction,
* creating_subid is the ID of the creating subxact; if created in a prior
* transaction, creating_subid is zero. If deleted during the current
* transaction, deleting_subid is the ID of the deleting subxact; if no
* deletion request is pending, deleting_subid is zero.
*/
SubTransactionId creating_subid;
SubTransactionId deleting_subid;
} OnCommitItem;
static List *on_commits = NIL;
/*
* State information for ALTER TABLE
*
* The pending-work queue for an ALTER TABLE is a List of AlteredTableInfo
* structs, one for each table modified by the operation (the named table
* plus any child tables that are affected). We save lists of subcommands
* to apply to this table (possibly modified by parse transformation steps);
* these lists will be executed in Phase 2. If a Phase 3 step is needed,
* necessary information is stored in the constraints and newvals lists.
*
* Phase 2 is divided into multiple passes; subcommands are executed in
* a pass determined by subcommand type.
*/
#define AT_PASS_DROP 0 /* DROP (all flavors) */
#define AT_PASS_ALTER_TYPE 1 /* ALTER COLUMN TYPE */
#define AT_PASS_OLD_INDEX 2 /* re-add existing indexes */
#define AT_PASS_OLD_CONSTR 3 /* re-add existing constraints */
#define AT_PASS_COL_ATTRS 4 /* set other column attributes */
/* We could support a RENAME COLUMN pass here, but not currently used */
#define AT_PASS_ADD_COL 5 /* ADD COLUMN */
#define AT_PASS_ADD_INDEX 6 /* ADD indexes */
#define AT_PASS_ADD_CONSTR 7 /* ADD constraints, defaults */
#define AT_PASS_MISC 8 /* other stuff */
#define AT_NUM_PASSES 9
typedef struct AlteredTableInfo
{
/* Information saved before any work commences: */
Oid relid; /* Relation to work on */
char relkind; /* Its relkind */
TupleDesc oldDesc; /* Pre-modification tuple descriptor */
/* Information saved by Phase 1 for Phase 2: */
2004-08-29 07:07:03 +02:00
List *subcmds[AT_NUM_PASSES]; /* Lists of AlterTableCmd */
/* Information saved by Phases 1/2 for Phase 3: */
List *constraints; /* List of NewConstraint */
List *newvals; /* List of NewColumnValue */
bool new_notnull; /* T if we added new NOT NULL constraints */
2011-02-15 04:37:37 +01:00
bool rewrite; /* T if a rewrite is forced */
Oid newTableSpace; /* new tablespace; 0 means no change */
/* Objects to rebuild after completing ALTER TYPE operations */
List *changedConstraintOids; /* OIDs of constraints to rebuild */
List *changedConstraintDefs; /* string definitions of same */
2004-08-29 07:07:03 +02:00
List *changedIndexOids; /* OIDs of indexes to rebuild */
List *changedIndexDefs; /* string definitions of same */
} AlteredTableInfo;
/* Struct describing one new constraint to check in Phase 3 scan */
/* Note: new NOT NULL constraints are handled elsewhere */
typedef struct NewConstraint
{
char *name; /* Constraint name, or NULL if none */
ConstrType contype; /* CHECK or FOREIGN */
Oid refrelid; /* PK rel, if FOREIGN */
Oid refindid; /* OID of PK's index, if FOREIGN */
Oid conid; /* OID of pg_constraint entry, if FOREIGN */
Node *qual; /* Check expr or CONSTR_FOREIGN Constraint */
List *qualstate; /* Execution state for CHECK */
} NewConstraint;
/*
* Struct describing one new column value that needs to be computed during
* Phase 3 copy (this could be either a new column with a non-null default, or
* a column that we're changing the type of). Columns without such an entry
* are just copied from the old table during ATRewriteTable. Note that the
* expr is an expression over *old* table values.
*/
typedef struct NewColumnValue
{
AttrNumber attnum; /* which column */
Expr *expr; /* expression to compute */
ExprState *exprstate; /* execution state */
} NewColumnValue;
/*
* Error-reporting support for RemoveRelations
*/
struct dropmsgstrings
{
char kind;
int nonexistent_code;
const char *nonexistent_msg;
const char *skipping_msg;
const char *nota_msg;
const char *drophint_msg;
};
static const struct dropmsgstrings dropmsgstringarray[] = {
{RELKIND_RELATION,
ERRCODE_UNDEFINED_TABLE,
gettext_noop("table \"%s\" does not exist"),
gettext_noop("table \"%s\" does not exist, skipping"),
gettext_noop("\"%s\" is not a table"),
gettext_noop("Use DROP TABLE to remove a table.")},
{RELKIND_SEQUENCE,
ERRCODE_UNDEFINED_TABLE,
gettext_noop("sequence \"%s\" does not exist"),
gettext_noop("sequence \"%s\" does not exist, skipping"),
gettext_noop("\"%s\" is not a sequence"),
gettext_noop("Use DROP SEQUENCE to remove a sequence.")},
{RELKIND_VIEW,
ERRCODE_UNDEFINED_TABLE,
gettext_noop("view \"%s\" does not exist"),
gettext_noop("view \"%s\" does not exist, skipping"),
gettext_noop("\"%s\" is not a view"),
gettext_noop("Use DROP VIEW to remove a view.")},
{RELKIND_MATVIEW,
ERRCODE_UNDEFINED_TABLE,
gettext_noop("materialized view \"%s\" does not exist"),
gettext_noop("materialized view \"%s\" does not exist, skipping"),
gettext_noop("\"%s\" is not a materialized view"),
gettext_noop("Use DROP MATERIALIZED VIEW to remove a materialized view.")},
{RELKIND_INDEX,
ERRCODE_UNDEFINED_OBJECT,
gettext_noop("index \"%s\" does not exist"),
gettext_noop("index \"%s\" does not exist, skipping"),
gettext_noop("\"%s\" is not an index"),
gettext_noop("Use DROP INDEX to remove an index.")},
{RELKIND_COMPOSITE_TYPE,
ERRCODE_UNDEFINED_OBJECT,
gettext_noop("type \"%s\" does not exist"),
gettext_noop("type \"%s\" does not exist, skipping"),
gettext_noop("\"%s\" is not a type"),
gettext_noop("Use DROP TYPE to remove a type.")},
{RELKIND_FOREIGN_TABLE,
ERRCODE_UNDEFINED_OBJECT,
gettext_noop("foreign table \"%s\" does not exist"),
gettext_noop("foreign table \"%s\" does not exist, skipping"),
gettext_noop("\"%s\" is not a foreign table"),
gettext_noop("Use DROP FOREIGN TABLE to remove a foreign table.")},
{'\0', 0, NULL, NULL, NULL, NULL}
};
Improve table locking behavior in the face of current DDL. In the previous coding, callers were faced with an awkward choice: look up the name, do permissions checks, and then lock the table; or look up the name, lock the table, and then do permissions checks. The first choice was wrong because the results of the name lookup and permissions checks might be out-of-date by the time the table lock was acquired, while the second allowed a user with no privileges to interfere with access to a table by users who do have privileges (e.g. if a malicious backend queues up for an AccessExclusiveLock on a table on which AccessShareLock is already held, further attempts to access the table will be blocked until the AccessExclusiveLock is obtained and the malicious backend's transaction rolls back). To fix, allow callers of RangeVarGetRelid() to pass a callback which gets executed after performing the name lookup but before acquiring the relation lock. If the name lookup is retried (because invalidation messages are received), the callback will be re-executed as well, so we get the best of both worlds. RangeVarGetRelid() is renamed to RangeVarGetRelidExtended(); callers not wishing to supply a callback can continue to invoke it as RangeVarGetRelid(), which is now a macro. Since the only one caller that uses nowait = true now passes a callback anyway, the RangeVarGetRelid() macro defaults nowait as well. The callback can also be used for supplemental locking - for example, REINDEX INDEX needs to acquire the table lock before the index lock to reduce deadlock possibilities. There's a lot more work to be done here to fix all the cases where this can be a problem, but this commit provides the general infrastructure and fixes the following specific cases: REINDEX INDEX, REINDEX TABLE, LOCK TABLE, and and DROP TABLE/INDEX/SEQUENCE/VIEW/FOREIGN TABLE. Per discussion with Noah Misch and Alvaro Herrera.
2011-11-30 16:12:27 +01:00
struct DropRelationCallbackState
{
char relkind;
Oid heapOid;
bool concurrent;
Improve table locking behavior in the face of current DDL. In the previous coding, callers were faced with an awkward choice: look up the name, do permissions checks, and then lock the table; or look up the name, lock the table, and then do permissions checks. The first choice was wrong because the results of the name lookup and permissions checks might be out-of-date by the time the table lock was acquired, while the second allowed a user with no privileges to interfere with access to a table by users who do have privileges (e.g. if a malicious backend queues up for an AccessExclusiveLock on a table on which AccessShareLock is already held, further attempts to access the table will be blocked until the AccessExclusiveLock is obtained and the malicious backend's transaction rolls back). To fix, allow callers of RangeVarGetRelid() to pass a callback which gets executed after performing the name lookup but before acquiring the relation lock. If the name lookup is retried (because invalidation messages are received), the callback will be re-executed as well, so we get the best of both worlds. RangeVarGetRelid() is renamed to RangeVarGetRelidExtended(); callers not wishing to supply a callback can continue to invoke it as RangeVarGetRelid(), which is now a macro. Since the only one caller that uses nowait = true now passes a callback anyway, the RangeVarGetRelid() macro defaults nowait as well. The callback can also be used for supplemental locking - for example, REINDEX INDEX needs to acquire the table lock before the index lock to reduce deadlock possibilities. There's a lot more work to be done here to fix all the cases where this can be a problem, but this commit provides the general infrastructure and fixes the following specific cases: REINDEX INDEX, REINDEX TABLE, LOCK TABLE, and and DROP TABLE/INDEX/SEQUENCE/VIEW/FOREIGN TABLE. Per discussion with Noah Misch and Alvaro Herrera.
2011-11-30 16:12:27 +01:00
};
/* Alter table target-type flags for ATSimplePermissions */
#define ATT_TABLE 0x0001
#define ATT_VIEW 0x0002
#define ATT_MATVIEW 0x0004
#define ATT_INDEX 0x0008
#define ATT_COMPOSITE_TYPE 0x0010
#define ATT_FOREIGN_TABLE 0x0020
static void truncate_check_rel(Relation rel);
static List *MergeAttributes(List *schema, List *supers, char relpersistence,
List **supOids, List **supconstr, int *supOidCount);
static bool MergeCheckConstraint(List *constraints, char *name, Node *expr);
static void MergeAttributesIntoExisting(Relation child_rel, Relation parent_rel);
static void MergeConstraintsIntoExisting(Relation child_rel, Relation parent_rel);
static void StoreCatalogInheritance(Oid relationId, List *supers);
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
static void StoreCatalogInheritance1(Oid relationId, Oid parentOid,
int16 seqNumber, Relation inhRelation);
static int findAttrByName(const char *attributeName, List *schema);
static void AlterIndexNamespaces(Relation classRel, Relation rel,
Oid oldNspOid, Oid newNspOid, ObjectAddresses *objsMoved);
static void AlterSeqNamespaces(Relation classRel, Relation rel,
Oid oldNspOid, Oid newNspOid, ObjectAddresses *objsMoved,
LOCKMODE lockmode);
static void ATExecValidateConstraint(Relation rel, char *constrName,
bool recurse, bool recursing, LOCKMODE lockmode);
static int transformColumnNameList(Oid relId, List *colList,
2003-08-04 02:43:34 +02:00
int16 *attnums, Oid *atttypids);
static int transformFkeyGetPrimaryKey(Relation pkrel, Oid *indexOid,
2004-08-29 07:07:03 +02:00
List **attnamelist,
int16 *attnums, Oid *atttypids,
Oid *opclasses);
2003-08-04 02:43:34 +02:00
static Oid transformFkeyCheckAttrs(Relation pkrel,
2004-08-29 07:07:03 +02:00
int numattrs, int16 *attnums,
Oid *opclasses);
static void checkFkeyPermissions(Relation rel, int16 *attnums, int natts);
static CoercionPathType findFkeyCast(Oid targetTypeId, Oid sourceTypeId,
Oid *funcid);
static void validateCheckConstraint(Relation rel, HeapTuple constrtup);
static void validateForeignKeyConstraint(char *conname,
Relation rel, Relation pkrel,
Oid pkindOid, Oid constraintOid);
static void createForeignKeyTriggers(Relation rel, Constraint *fkconstraint,
Oid constraintOid, Oid indexOid);
static void ATController(Relation rel, List *cmds, bool recurse, LOCKMODE lockmode);
static void ATPrepCmd(List **wqueue, Relation rel, AlterTableCmd *cmd,
bool recurse, bool recursing, LOCKMODE lockmode);
static void ATRewriteCatalogs(List **wqueue, LOCKMODE lockmode);
static void ATExecCmd(List **wqueue, AlteredTableInfo *tab, Relation rel,
AlterTableCmd *cmd, LOCKMODE lockmode);
static void ATRewriteTables(List **wqueue, LOCKMODE lockmode);
static void ATRewriteTable(AlteredTableInfo *tab, Oid OIDNewHeap, LOCKMODE lockmode);
static AlteredTableInfo *ATGetQueueEntry(List **wqueue, Relation rel);
static void ATSimplePermissions(Relation rel, int allowed_targets);
static void ATWrongRelkindError(Relation rel, int allowed_targets);
static void ATSimpleRecursion(List **wqueue, Relation rel,
AlterTableCmd *cmd, bool recurse, LOCKMODE lockmode);
static void ATTypedTableRecursion(List **wqueue, Relation rel, AlterTableCmd *cmd,
2011-04-10 17:42:00 +02:00
LOCKMODE lockmode);
static List *find_typed_table_dependencies(Oid typeOid, const char *typeName,
2011-04-10 17:42:00 +02:00
DropBehavior behavior);
static void ATPrepAddColumn(List **wqueue, Relation rel, bool recurse, bool recursing,
AlterTableCmd *cmd, LOCKMODE lockmode);
static void ATExecAddColumn(List **wqueue, AlteredTableInfo *tab, Relation rel,
ColumnDef *colDef, bool isOid,
bool recurse, bool recursing, LOCKMODE lockmode);
static void check_for_column_name_collision(Relation rel, const char *colname);
static void add_column_datatype_dependency(Oid relid, int32 attnum, Oid typid);
static void add_column_collation_dependency(Oid relid, int32 attnum, Oid collid);
static void ATPrepAddOids(List **wqueue, Relation rel, bool recurse,
AlterTableCmd *cmd, LOCKMODE lockmode);
static void ATExecDropNotNull(Relation rel, const char *colName, LOCKMODE lockmode);
static void ATExecSetNotNull(AlteredTableInfo *tab, Relation rel,
const char *colName, LOCKMODE lockmode);
static void ATExecColumnDefault(Relation rel, const char *colName,
Node *newDefault, LOCKMODE lockmode);
static void ATPrepSetStatistics(Relation rel, const char *colName,
Node *newValue, LOCKMODE lockmode);
static void ATExecSetStatistics(Relation rel, const char *colName,
Node *newValue, LOCKMODE lockmode);
static void ATExecSetOptions(Relation rel, const char *colName,
Node *options, bool isReset, LOCKMODE lockmode);
static void ATExecSetStorage(Relation rel, const char *colName,
Node *newValue, LOCKMODE lockmode);
static void ATPrepDropColumn(List **wqueue, Relation rel, bool recurse, bool recursing,
2011-04-10 17:42:00 +02:00
AlterTableCmd *cmd, LOCKMODE lockmode);
static void ATExecDropColumn(List **wqueue, Relation rel, const char *colName,
2004-08-29 07:07:03 +02:00
DropBehavior behavior,
bool recurse, bool recursing,
bool missing_ok, LOCKMODE lockmode);
static void ATExecAddIndex(AlteredTableInfo *tab, Relation rel,
IndexStmt *stmt, bool is_rebuild, LOCKMODE lockmode);
static void ATExecAddConstraint(List **wqueue,
AlteredTableInfo *tab, Relation rel,
Constraint *newConstraint, bool recurse, bool is_readd,
LOCKMODE lockmode);
static void ATExecAddIndexConstraint(AlteredTableInfo *tab, Relation rel,
2011-04-10 17:42:00 +02:00
IndexStmt *stmt, LOCKMODE lockmode);
static void ATAddCheckConstraint(List **wqueue,
AlteredTableInfo *tab, Relation rel,
Constraint *constr,
bool recurse, bool recursing, bool is_readd,
LOCKMODE lockmode);
static void ATAddForeignKeyConstraint(AlteredTableInfo *tab, Relation rel,
Constraint *fkconstraint, LOCKMODE lockmode);
static void ATExecDropConstraint(Relation rel, const char *constrName,
2010-02-26 03:01:40 +01:00
DropBehavior behavior,
bool recurse, bool recursing,
bool missing_ok, LOCKMODE lockmode);
static void ATPrepAlterColumnType(List **wqueue,
2004-08-29 07:07:03 +02:00
AlteredTableInfo *tab, Relation rel,
bool recurse, bool recursing,
AlterTableCmd *cmd, LOCKMODE lockmode);
static bool ATColumnChangeRequiresRewrite(Node *expr, AttrNumber varattno);
static void ATExecAlterColumnType(AlteredTableInfo *tab, Relation rel,
2011-04-10 17:42:00 +02:00
AlterTableCmd *cmd, LOCKMODE lockmode);
static void ATExecAlterColumnGenericOptions(Relation rel, const char *colName,
List *options, LOCKMODE lockmode);
static void ATPostAlterTypeCleanup(List **wqueue, AlteredTableInfo *tab, LOCKMODE lockmode);
static void ATPostAlterTypeParse(Oid oldId, char *cmd,
List **wqueue, LOCKMODE lockmode, bool rewrite);
static void TryReuseIndex(Oid oldId, IndexStmt *stmt);
static void TryReuseForeignKey(Oid oldId, Constraint *con);
static void change_owner_fix_column_acls(Oid relationOid,
Oid oldOwnerId, Oid newOwnerId);
static void change_owner_recurse_to_sequences(Oid relationOid,
Oid newOwnerId, LOCKMODE lockmode);
static void ATExecClusterOn(Relation rel, const char *indexName, LOCKMODE lockmode);
static void ATExecDropCluster(Relation rel, LOCKMODE lockmode);
static void ATPrepSetTableSpace(AlteredTableInfo *tab, Relation rel,
char *tablespacename, LOCKMODE lockmode);
static void ATExecSetTableSpace(Oid tableOid, Oid newTableSpace, LOCKMODE lockmode);
static void ATExecSetRelOptions(Relation rel, List *defList,
AlterTableType operation,
LOCKMODE lockmode);
static void ATExecEnableDisableTrigger(Relation rel, char *trigname,
2011-04-10 17:42:00 +02:00
char fires_when, bool skip_system, LOCKMODE lockmode);
Changes pg_trigger and extend pg_rewrite in order to allow triggers and rules to be defined with different, per session controllable, behaviors for replication purposes. This will allow replication systems like Slony-I and, as has been stated on pgsql-hackers, other products to control the firing mechanism of triggers and rewrite rules without modifying the system catalog directly. The firing mechanisms are controlled by a new superuser-only GUC variable, session_replication_role, together with a change to pg_trigger.tgenabled and a new column pg_rewrite.ev_enabled. Both columns are a single char data type now (tgenabled was a bool before). The possible values in these attributes are: 'O' - Trigger/Rule fires when session_replication_role is "origin" (default) or "local". This is the default behavior. 'D' - Trigger/Rule is disabled and fires never 'A' - Trigger/Rule fires always regardless of the setting of session_replication_role 'R' - Trigger/Rule fires when session_replication_role is "replica" The GUC variable can only be changed as long as the system does not have any cached query plans. This will prevent changing the session role and accidentally executing stored procedures or functions that have plans cached that expand to the wrong query set due to differences in the rule firing semantics. The SQL syntax for changing a triggers/rules firing semantics is ALTER TABLE <tabname> <when> TRIGGER|RULE <name>; <when> ::= ENABLE | ENABLE ALWAYS | ENABLE REPLICA | DISABLE psql's \d command as well as pg_dump are extended in a backward compatible fashion. Jan
2007-03-20 00:38:32 +01:00
static void ATExecEnableDisableRule(Relation rel, char *rulename,
char fires_when, LOCKMODE lockmode);
static void ATPrepAddInherit(Relation child_rel);
static void ATExecAddInherit(Relation child_rel, RangeVar *parent, LOCKMODE lockmode);
static void ATExecDropInherit(Relation rel, RangeVar *parent, LOCKMODE lockmode);
static void drop_parent_dependency(Oid relid, Oid refclassid, Oid refobjid);
static void ATExecAddOf(Relation rel, const TypeName *ofTypename, LOCKMODE lockmode);
static void ATExecDropOf(Relation rel, LOCKMODE lockmode);
static void ATExecGenericOptions(Relation rel, List *options);
static void copy_relation_data(SMgrRelation rel, SMgrRelation dst,
ForkNumber forkNum, char relpersistence);
static const char *storage_name(char c);
Improve table locking behavior in the face of current DDL. In the previous coding, callers were faced with an awkward choice: look up the name, do permissions checks, and then lock the table; or look up the name, lock the table, and then do permissions checks. The first choice was wrong because the results of the name lookup and permissions checks might be out-of-date by the time the table lock was acquired, while the second allowed a user with no privileges to interfere with access to a table by users who do have privileges (e.g. if a malicious backend queues up for an AccessExclusiveLock on a table on which AccessShareLock is already held, further attempts to access the table will be blocked until the AccessExclusiveLock is obtained and the malicious backend's transaction rolls back). To fix, allow callers of RangeVarGetRelid() to pass a callback which gets executed after performing the name lookup but before acquiring the relation lock. If the name lookup is retried (because invalidation messages are received), the callback will be re-executed as well, so we get the best of both worlds. RangeVarGetRelid() is renamed to RangeVarGetRelidExtended(); callers not wishing to supply a callback can continue to invoke it as RangeVarGetRelid(), which is now a macro. Since the only one caller that uses nowait = true now passes a callback anyway, the RangeVarGetRelid() macro defaults nowait as well. The callback can also be used for supplemental locking - for example, REINDEX INDEX needs to acquire the table lock before the index lock to reduce deadlock possibilities. There's a lot more work to be done here to fix all the cases where this can be a problem, but this commit provides the general infrastructure and fixes the following specific cases: REINDEX INDEX, REINDEX TABLE, LOCK TABLE, and and DROP TABLE/INDEX/SEQUENCE/VIEW/FOREIGN TABLE. Per discussion with Noah Misch and Alvaro Herrera.
2011-11-30 16:12:27 +01:00
static void RangeVarCallbackForDropRelation(const RangeVar *rel, Oid relOid,
Oid oldRelOid, void *arg);
static void RangeVarCallbackForAlterRelation(const RangeVar *rv, Oid relid,
Oid oldrelid, void *arg);
Improve table locking behavior in the face of current DDL. In the previous coding, callers were faced with an awkward choice: look up the name, do permissions checks, and then lock the table; or look up the name, lock the table, and then do permissions checks. The first choice was wrong because the results of the name lookup and permissions checks might be out-of-date by the time the table lock was acquired, while the second allowed a user with no privileges to interfere with access to a table by users who do have privileges (e.g. if a malicious backend queues up for an AccessExclusiveLock on a table on which AccessShareLock is already held, further attempts to access the table will be blocked until the AccessExclusiveLock is obtained and the malicious backend's transaction rolls back). To fix, allow callers of RangeVarGetRelid() to pass a callback which gets executed after performing the name lookup but before acquiring the relation lock. If the name lookup is retried (because invalidation messages are received), the callback will be re-executed as well, so we get the best of both worlds. RangeVarGetRelid() is renamed to RangeVarGetRelidExtended(); callers not wishing to supply a callback can continue to invoke it as RangeVarGetRelid(), which is now a macro. Since the only one caller that uses nowait = true now passes a callback anyway, the RangeVarGetRelid() macro defaults nowait as well. The callback can also be used for supplemental locking - for example, REINDEX INDEX needs to acquire the table lock before the index lock to reduce deadlock possibilities. There's a lot more work to be done here to fix all the cases where this can be a problem, but this commit provides the general infrastructure and fixes the following specific cases: REINDEX INDEX, REINDEX TABLE, LOCK TABLE, and and DROP TABLE/INDEX/SEQUENCE/VIEW/FOREIGN TABLE. Per discussion with Noah Misch and Alvaro Herrera.
2011-11-30 16:12:27 +01:00
/* ----------------------------------------------------------------
* DefineRelation
* Creates a new relation.
*
* stmt carries parsetree information from an ordinary CREATE TABLE statement.
* The other arguments are used to extend the behavior for other cases:
* relkind: relkind to assign to the new relation
* ownerId: if not InvalidOid, use this as the new relation's owner.
*
* Note that permissions checks are done against current user regardless of
* ownerId. A nonzero ownerId is used when someone is creating a relation
* "on behalf of" someone else, so we still want to see that the current user
* has permissions to do it.
*
* If successful, returns the OID of the new relation.
* ----------------------------------------------------------------
*/
Oid
DefineRelation(CreateStmt *stmt, char relkind, Oid ownerId)
{
char relname[NAMEDATALEN];
Oid namespaceId;
List *schema = stmt->tableElts;
Oid relationId;
Oid tablespaceId;
Relation rel;
TupleDesc descriptor;
List *inheritOids;
List *old_constraints;
bool localHasOids;
int parentOidCount;
List *rawDefaults;
List *cookedDefaults;
Datum reloptions;
ListCell *listptr;
AttrNumber attnum;
static char *validnsps[] = HEAP_RELOPT_NAMESPACES;
Oid ofTypeId;
/*
2005-10-15 04:49:52 +02:00
* Truncate relname to appropriate length (probably a waste of time, as
* parser should have done this already).
*/
StrNCpy(relname, stmt->relation->relname, NAMEDATALEN);
/*
* Check consistency of arguments
*/
2011-04-10 17:42:00 +02:00
if (stmt->oncommit != ONCOMMIT_NOOP
&& stmt->relation->relpersistence != RELPERSISTENCE_TEMP)
ereport(ERROR,
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
2005-10-15 04:49:52 +02:00
errmsg("ON COMMIT can only be used on temporary tables")));
if (stmt->constraints != NIL && relkind == RELKIND_FOREIGN_TABLE)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("constraints are not supported on foreign tables")));
/*
* Look up the namespace in which we are supposed to create the relation,
* check we have permission to create there, lock it against concurrent
* drop, and mark stmt->relation as RELPERSISTENCE_TEMP if a temporary
* namespace is selected.
*/
namespaceId =
RangeVarGetAndCheckCreationNamespace(stmt->relation, NoLock, NULL);
2009-12-09 22:57:51 +01:00
/*
* Security check: disallow creating temp tables from security-restricted
* code. This is needed because calling code might not expect untrusted
* tables to appear in pg_temp at the front of its search path.
*/
if (stmt->relation->relpersistence == RELPERSISTENCE_TEMP
&& InSecurityRestrictedOperation())
2009-12-09 22:57:51 +01:00
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
errmsg("cannot create temporary table within security-restricted operation")));
/*
* Select tablespace to use. If not specified, use default tablespace
* (which may in turn default to database's default).
*/
if (stmt->tablespacename)
{
tablespaceId = get_tablespace_oid(stmt->tablespacename, false);
}
else
{
tablespaceId = GetDefaultTablespace(stmt->relation->relpersistence);
/* note InvalidOid is OK in this case */
}
/* Check permissions except when using database's default */
if (OidIsValid(tablespaceId) && tablespaceId != MyDatabaseTableSpace)
{
AclResult aclresult;
aclresult = pg_tablespace_aclcheck(tablespaceId, GetUserId(),
ACL_CREATE);
if (aclresult != ACLCHECK_OK)
aclcheck_error(aclresult, ACL_KIND_TABLESPACE,
get_tablespace_name(tablespaceId));
}
/* In all cases disallow placing user relations in pg_global */
if (tablespaceId == GLOBALTABLESPACE_OID)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("only shared relations can be placed in pg_global tablespace")));
/* Identify user ID that will own the table */
if (!OidIsValid(ownerId))
ownerId = GetUserId();
/*
* Parse and validate reloptions, if any.
*/
reloptions = transformRelOptions((Datum) 0, stmt->options, NULL, validnsps,
true, false);
(void) heap_reloptions(relkind, reloptions, true);
if (stmt->ofTypename)
{
AclResult aclresult;
ofTypeId = typenameTypeId(NULL, stmt->ofTypename);
aclresult = pg_type_aclcheck(ofTypeId, GetUserId(), ACL_USAGE);
if (aclresult != ACLCHECK_OK)
aclcheck_error_type(aclresult, ofTypeId);
}
else
ofTypeId = InvalidOid;
/*
2005-10-15 04:49:52 +02:00
* Look up inheritance ancestors and generate relation schema, including
* inherited attributes.
*/
schema = MergeAttributes(schema, stmt->inhRelations,
stmt->relation->relpersistence,
2005-10-15 04:49:52 +02:00
&inheritOids, &old_constraints, &parentOidCount);
/*
* Create a tuple descriptor from the relation schema. Note that this
* deals with column names, types, and NOT NULL constraints, but not
* default values or CHECK constraints; we handle those below.
*/
descriptor = BuildDescForRelation(schema);
localHasOids = interpretOidsOption(stmt->options,
(relkind == RELKIND_RELATION ||
relkind == RELKIND_FOREIGN_TABLE));
descriptor->tdhasoid = (localHasOids || parentOidCount > 0);
/*
* Find columns with default values and prepare for insertion of the
* defaults. Pre-cooked (that is, inherited) defaults go into a list of
* CookedConstraint structs that we'll pass to heap_create_with_catalog,
* while raw defaults go into a list of RawColumnDefault structs that will
* be processed by AddRelationNewConstraints. (We can't deal with raw
* expressions until we can do transformExpr.)
*
* We can set the atthasdef flags now in the tuple descriptor; this just
* saves StoreAttrDefault from having to do an immediate update of the
* pg_attribute rows.
*/
rawDefaults = NIL;
cookedDefaults = NIL;
attnum = 0;
foreach(listptr, schema)
{
ColumnDef *colDef = lfirst(listptr);
attnum++;
2007-11-15 22:14:46 +01:00
if (colDef->raw_default != NULL)
{
RawColumnDefault *rawEnt;
2004-08-29 07:07:03 +02:00
Assert(colDef->cooked_default == NULL);
rawEnt = (RawColumnDefault *) palloc(sizeof(RawColumnDefault));
rawEnt->attnum = attnum;
rawEnt->raw_default = colDef->raw_default;
rawDefaults = lappend(rawDefaults, rawEnt);
descriptor->attrs[attnum - 1]->atthasdef = true;
}
else if (colDef->cooked_default != NULL)
{
CookedConstraint *cooked;
cooked = (CookedConstraint *) palloc(sizeof(CookedConstraint));
cooked->contype = CONSTR_DEFAULT;
cooked->name = NULL;
cooked->attnum = attnum;
cooked->expr = colDef->cooked_default;
cooked->skip_validation = false;
cooked->is_local = true; /* not used for defaults */
cooked->inhcount = 0; /* ditto */
cooked->is_no_inherit = false;
cookedDefaults = lappend(cookedDefaults, cooked);
descriptor->attrs[attnum - 1]->atthasdef = true;
}
}
/*
* Create the relation. Inherited defaults and constraints are passed in
* for immediate handling --- since they don't need parsing, they can be
* stored immediately.
*/
relationId = heap_create_with_catalog(relname,
namespaceId,
tablespaceId,
InvalidOid,
InvalidOid,
ofTypeId,
ownerId,
descriptor,
list_concat(cookedDefaults,
old_constraints),
relkind,
stmt->relation->relpersistence,
false,
false,
localHasOids,
parentOidCount,
stmt->oncommit,
reloptions,
true,
allowSystemTableMods,
false);
/* Store inheritance information for new rel. */
StoreCatalogInheritance(relationId, inheritOids);
/*
* We must bump the command counter to make the newly-created relation
* tuple visible for opening.
*/
CommandCounterIncrement();
/*
* Open the new relation and acquire exclusive lock on it. This isn't
2005-10-15 04:49:52 +02:00
* really necessary for locking out other backends (since they can't see
* the new rel anyway until we commit), but it keeps the lock manager from
* complaining about deadlock risks.
*/
rel = relation_open(relationId, AccessExclusiveLock);
/*
2005-10-15 04:49:52 +02:00
* Now add any newly specified column default values and CHECK constraints
* to the new relation. These are passed to us in the form of raw
* parsetrees; we need to transform them to executable expression trees
* before they can be added. The most convenient way to do that is to
* apply the parser's transformExpr routine, but transformExpr doesn't
* work unless we have a pre-existing relation. So, the transformation has
* to be postponed to this final step of CREATE TABLE.
*/
if (rawDefaults || stmt->constraints)
AddRelationNewConstraints(rel, rawDefaults, stmt->constraints,
true, true, false);
/*
* Clean up. We keep lock on new relation (although it shouldn't be
* visible to anyone else anyway, until commit).
*/
relation_close(rel, NoLock);
return relationId;
}
/*
* Emit the right error or warning message for a "DROP" command issued on a
* non-existent relation
*/
static void
DropErrorMsgNonExistent(const char *relname, char rightkind, bool missing_ok)
{
const struct dropmsgstrings *rentry;
for (rentry = dropmsgstringarray; rentry->kind != '\0'; rentry++)
{
if (rentry->kind == rightkind)
{
if (!missing_ok)
{
ereport(ERROR,
(errcode(rentry->nonexistent_code),
errmsg(rentry->nonexistent_msg, relname)));
}
else
{
ereport(NOTICE, (errmsg(rentry->skipping_msg, relname)));
break;
}
}
}
Assert(rentry->kind != '\0'); /* Should be impossible */
}
/*
* Emit the right error message for a "DROP" command issued on a
* relation of the wrong type
*/
static void
DropErrorMsgWrongType(const char *relname, char wrongkind, char rightkind)
{
const struct dropmsgstrings *rentry;
const struct dropmsgstrings *wentry;
for (rentry = dropmsgstringarray; rentry->kind != '\0'; rentry++)
if (rentry->kind == rightkind)
break;
Assert(rentry->kind != '\0');
for (wentry = dropmsgstringarray; wentry->kind != '\0'; wentry++)
if (wentry->kind == wrongkind)
break;
/* wrongkind could be something we don't have in our table... */
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg(rentry->nota_msg, relname),
(wentry->kind != '\0') ? errhint("%s", _(wentry->drophint_msg)) : 0));
}
/*
* RemoveRelations
* Implements DROP TABLE, DROP INDEX, DROP SEQUENCE, DROP VIEW,
* DROP MATERIALIZED VIEW, DROP FOREIGN TABLE
*/
void
RemoveRelations(DropStmt *drop)
{
ObjectAddresses *objects;
char relkind;
ListCell *cell;
int flags = 0;
LOCKMODE lockmode = AccessExclusiveLock;
Fix assorted bugs in CREATE/DROP INDEX CONCURRENTLY. Commit 8cb53654dbdb4c386369eb988062d0bbb6de725e, which introduced DROP INDEX CONCURRENTLY, managed to break CREATE INDEX CONCURRENTLY via a poor choice of catalog state representation. The pg_index state for an index that's reached the final pre-drop stage was the same as the state for an index just created by CREATE INDEX CONCURRENTLY. This meant that the (necessary) change to make RelationGetIndexList ignore about-to-die indexes also made it ignore freshly-created indexes; which is catastrophic because the latter do need to be considered in HOT-safety decisions. Failure to do so leads to incorrect index entries and subsequently wrong results from queries depending on the concurrently-created index. To fix, add an additional boolean column "indislive" to pg_index, so that the freshly-created and about-to-die states can be distinguished. (This change obviously is only possible in HEAD. This patch will need to be back-patched, but in 9.2 we'll use a kluge consisting of overloading the formerly-impossible state of indisvalid = true and indisready = false.) In addition, change CREATE/DROP INDEX CONCURRENTLY so that the pg_index flag changes they make without exclusive lock on the index are made via heap_inplace_update() rather than a normal transactional update. The latter is not very safe because moving the pg_index tuple could result in concurrent SnapshotNow scans finding it twice or not at all, thus possibly resulting in index corruption. This is a pre-existing bug in CREATE INDEX CONCURRENTLY, which was copied into the DROP code. In addition, fix various places in the code that ought to check to make sure that the indexes they are manipulating are valid and/or ready as appropriate. These represent bugs that have existed since 8.2, since a failed CREATE INDEX CONCURRENTLY could leave a corrupt or invalid index behind, and we ought not try to do anything that might fail with such an index. Also fix RelationReloadIndexInfo to ensure it copies all the pg_index columns that are allowed to change after initial creation. Previously we could have been left with stale values of some fields in an index relcache entry. It's not clear whether this actually had any user-visible consequences, but it's at least a bug waiting to happen. In addition, do some code and docs review for DROP INDEX CONCURRENTLY; some cosmetic code cleanup but mostly addition and revision of comments. This will need to be back-patched, but in a noticeably different form, so I'm committing it to HEAD before working on the back-patch. Problem reported by Amit Kapila, diagnosis by Pavan Deolassee, fix by Tom Lane and Andres Freund.
2012-11-29 03:25:27 +01:00
/* DROP CONCURRENTLY uses a weaker lock, and has some restrictions */
if (drop->concurrent)
{
Fix assorted bugs in CREATE/DROP INDEX CONCURRENTLY. Commit 8cb53654dbdb4c386369eb988062d0bbb6de725e, which introduced DROP INDEX CONCURRENTLY, managed to break CREATE INDEX CONCURRENTLY via a poor choice of catalog state representation. The pg_index state for an index that's reached the final pre-drop stage was the same as the state for an index just created by CREATE INDEX CONCURRENTLY. This meant that the (necessary) change to make RelationGetIndexList ignore about-to-die indexes also made it ignore freshly-created indexes; which is catastrophic because the latter do need to be considered in HOT-safety decisions. Failure to do so leads to incorrect index entries and subsequently wrong results from queries depending on the concurrently-created index. To fix, add an additional boolean column "indislive" to pg_index, so that the freshly-created and about-to-die states can be distinguished. (This change obviously is only possible in HEAD. This patch will need to be back-patched, but in 9.2 we'll use a kluge consisting of overloading the formerly-impossible state of indisvalid = true and indisready = false.) In addition, change CREATE/DROP INDEX CONCURRENTLY so that the pg_index flag changes they make without exclusive lock on the index are made via heap_inplace_update() rather than a normal transactional update. The latter is not very safe because moving the pg_index tuple could result in concurrent SnapshotNow scans finding it twice or not at all, thus possibly resulting in index corruption. This is a pre-existing bug in CREATE INDEX CONCURRENTLY, which was copied into the DROP code. In addition, fix various places in the code that ought to check to make sure that the indexes they are manipulating are valid and/or ready as appropriate. These represent bugs that have existed since 8.2, since a failed CREATE INDEX CONCURRENTLY could leave a corrupt or invalid index behind, and we ought not try to do anything that might fail with such an index. Also fix RelationReloadIndexInfo to ensure it copies all the pg_index columns that are allowed to change after initial creation. Previously we could have been left with stale values of some fields in an index relcache entry. It's not clear whether this actually had any user-visible consequences, but it's at least a bug waiting to happen. In addition, do some code and docs review for DROP INDEX CONCURRENTLY; some cosmetic code cleanup but mostly addition and revision of comments. This will need to be back-patched, but in a noticeably different form, so I'm committing it to HEAD before working on the back-patch. Problem reported by Amit Kapila, diagnosis by Pavan Deolassee, fix by Tom Lane and Andres Freund.
2012-11-29 03:25:27 +01:00
flags |= PERFORM_DELETION_CONCURRENTLY;
lockmode = ShareUpdateExclusiveLock;
Fix assorted bugs in CREATE/DROP INDEX CONCURRENTLY. Commit 8cb53654dbdb4c386369eb988062d0bbb6de725e, which introduced DROP INDEX CONCURRENTLY, managed to break CREATE INDEX CONCURRENTLY via a poor choice of catalog state representation. The pg_index state for an index that's reached the final pre-drop stage was the same as the state for an index just created by CREATE INDEX CONCURRENTLY. This meant that the (necessary) change to make RelationGetIndexList ignore about-to-die indexes also made it ignore freshly-created indexes; which is catastrophic because the latter do need to be considered in HOT-safety decisions. Failure to do so leads to incorrect index entries and subsequently wrong results from queries depending on the concurrently-created index. To fix, add an additional boolean column "indislive" to pg_index, so that the freshly-created and about-to-die states can be distinguished. (This change obviously is only possible in HEAD. This patch will need to be back-patched, but in 9.2 we'll use a kluge consisting of overloading the formerly-impossible state of indisvalid = true and indisready = false.) In addition, change CREATE/DROP INDEX CONCURRENTLY so that the pg_index flag changes they make without exclusive lock on the index are made via heap_inplace_update() rather than a normal transactional update. The latter is not very safe because moving the pg_index tuple could result in concurrent SnapshotNow scans finding it twice or not at all, thus possibly resulting in index corruption. This is a pre-existing bug in CREATE INDEX CONCURRENTLY, which was copied into the DROP code. In addition, fix various places in the code that ought to check to make sure that the indexes they are manipulating are valid and/or ready as appropriate. These represent bugs that have existed since 8.2, since a failed CREATE INDEX CONCURRENTLY could leave a corrupt or invalid index behind, and we ought not try to do anything that might fail with such an index. Also fix RelationReloadIndexInfo to ensure it copies all the pg_index columns that are allowed to change after initial creation. Previously we could have been left with stale values of some fields in an index relcache entry. It's not clear whether this actually had any user-visible consequences, but it's at least a bug waiting to happen. In addition, do some code and docs review for DROP INDEX CONCURRENTLY; some cosmetic code cleanup but mostly addition and revision of comments. This will need to be back-patched, but in a noticeably different form, so I'm committing it to HEAD before working on the back-patch. Problem reported by Amit Kapila, diagnosis by Pavan Deolassee, fix by Tom Lane and Andres Freund.
2012-11-29 03:25:27 +01:00
Assert(drop->removeType == OBJECT_INDEX);
if (list_length(drop->objects) != 1)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("DROP INDEX CONCURRENTLY does not support dropping multiple objects")));
if (drop->behavior == DROP_CASCADE)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("DROP INDEX CONCURRENTLY does not support CASCADE")));
}
/*
* First we identify all the relations, then we delete them in a single
* performMultipleDeletions() call. This is to avoid unwanted DROP
* RESTRICT errors if one of the relations depends on another.
*/
/* Determine required relkind */
switch (drop->removeType)
{
case OBJECT_TABLE:
relkind = RELKIND_RELATION;
break;
case OBJECT_INDEX:
relkind = RELKIND_INDEX;
break;
case OBJECT_SEQUENCE:
relkind = RELKIND_SEQUENCE;
break;
case OBJECT_VIEW:
relkind = RELKIND_VIEW;
break;
case OBJECT_MATVIEW:
relkind = RELKIND_MATVIEW;
break;
case OBJECT_FOREIGN_TABLE:
relkind = RELKIND_FOREIGN_TABLE;
break;
default:
elog(ERROR, "unrecognized drop object type: %d",
(int) drop->removeType);
relkind = 0; /* keep compiler quiet */
break;
}
/* Lock and validate each relation; build a list of object addresses */
objects = new_object_addresses();
foreach(cell, drop->objects)
{
RangeVar *rel = makeRangeVarFromNameList((List *) lfirst(cell));
Oid relOid;
ObjectAddress obj;
struct DropRelationCallbackState state;
/*
* These next few steps are a great deal like relation_openrv, but we
* don't bother building a relcache entry since we don't need it.
*
* Check for shared-cache-inval messages before trying to access the
* relation. This is needed to cover the case where the name
* identifies a rel that has been dropped and recreated since the
* start of our transaction: if we don't flush the old syscache entry,
* then we'll latch onto that entry and suffer an error later.
*/
AcceptInvalidationMessages();
Improve table locking behavior in the face of current DDL. In the previous coding, callers were faced with an awkward choice: look up the name, do permissions checks, and then lock the table; or look up the name, lock the table, and then do permissions checks. The first choice was wrong because the results of the name lookup and permissions checks might be out-of-date by the time the table lock was acquired, while the second allowed a user with no privileges to interfere with access to a table by users who do have privileges (e.g. if a malicious backend queues up for an AccessExclusiveLock on a table on which AccessShareLock is already held, further attempts to access the table will be blocked until the AccessExclusiveLock is obtained and the malicious backend's transaction rolls back). To fix, allow callers of RangeVarGetRelid() to pass a callback which gets executed after performing the name lookup but before acquiring the relation lock. If the name lookup is retried (because invalidation messages are received), the callback will be re-executed as well, so we get the best of both worlds. RangeVarGetRelid() is renamed to RangeVarGetRelidExtended(); callers not wishing to supply a callback can continue to invoke it as RangeVarGetRelid(), which is now a macro. Since the only one caller that uses nowait = true now passes a callback anyway, the RangeVarGetRelid() macro defaults nowait as well. The callback can also be used for supplemental locking - for example, REINDEX INDEX needs to acquire the table lock before the index lock to reduce deadlock possibilities. There's a lot more work to be done here to fix all the cases where this can be a problem, but this commit provides the general infrastructure and fixes the following specific cases: REINDEX INDEX, REINDEX TABLE, LOCK TABLE, and and DROP TABLE/INDEX/SEQUENCE/VIEW/FOREIGN TABLE. Per discussion with Noah Misch and Alvaro Herrera.
2011-11-30 16:12:27 +01:00
/* Look up the appropriate relation using namespace search. */
state.relkind = relkind;
state.heapOid = InvalidOid;
state.concurrent = drop->concurrent;
relOid = RangeVarGetRelidExtended(rel, lockmode, true,
Improve table locking behavior in the face of current DDL. In the previous coding, callers were faced with an awkward choice: look up the name, do permissions checks, and then lock the table; or look up the name, lock the table, and then do permissions checks. The first choice was wrong because the results of the name lookup and permissions checks might be out-of-date by the time the table lock was acquired, while the second allowed a user with no privileges to interfere with access to a table by users who do have privileges (e.g. if a malicious backend queues up for an AccessExclusiveLock on a table on which AccessShareLock is already held, further attempts to access the table will be blocked until the AccessExclusiveLock is obtained and the malicious backend's transaction rolls back). To fix, allow callers of RangeVarGetRelid() to pass a callback which gets executed after performing the name lookup but before acquiring the relation lock. If the name lookup is retried (because invalidation messages are received), the callback will be re-executed as well, so we get the best of both worlds. RangeVarGetRelid() is renamed to RangeVarGetRelidExtended(); callers not wishing to supply a callback can continue to invoke it as RangeVarGetRelid(), which is now a macro. Since the only one caller that uses nowait = true now passes a callback anyway, the RangeVarGetRelid() macro defaults nowait as well. The callback can also be used for supplemental locking - for example, REINDEX INDEX needs to acquire the table lock before the index lock to reduce deadlock possibilities. There's a lot more work to be done here to fix all the cases where this can be a problem, but this commit provides the general infrastructure and fixes the following specific cases: REINDEX INDEX, REINDEX TABLE, LOCK TABLE, and and DROP TABLE/INDEX/SEQUENCE/VIEW/FOREIGN TABLE. Per discussion with Noah Misch and Alvaro Herrera.
2011-11-30 16:12:27 +01:00
false,
RangeVarCallbackForDropRelation,
(void *) &state);
/* Not there? */
if (!OidIsValid(relOid))
{
DropErrorMsgNonExistent(rel->relname, relkind, drop->missing_ok);
continue;
}
/* OK, we're ready to delete this one */
obj.classId = RelationRelationId;
obj.objectId = relOid;
obj.objectSubId = 0;
add_exact_object_address(&obj, objects);
}
performMultipleDeletions(objects, drop->behavior, flags);
free_object_addresses(objects);
}
Improve table locking behavior in the face of current DDL. In the previous coding, callers were faced with an awkward choice: look up the name, do permissions checks, and then lock the table; or look up the name, lock the table, and then do permissions checks. The first choice was wrong because the results of the name lookup and permissions checks might be out-of-date by the time the table lock was acquired, while the second allowed a user with no privileges to interfere with access to a table by users who do have privileges (e.g. if a malicious backend queues up for an AccessExclusiveLock on a table on which AccessShareLock is already held, further attempts to access the table will be blocked until the AccessExclusiveLock is obtained and the malicious backend's transaction rolls back). To fix, allow callers of RangeVarGetRelid() to pass a callback which gets executed after performing the name lookup but before acquiring the relation lock. If the name lookup is retried (because invalidation messages are received), the callback will be re-executed as well, so we get the best of both worlds. RangeVarGetRelid() is renamed to RangeVarGetRelidExtended(); callers not wishing to supply a callback can continue to invoke it as RangeVarGetRelid(), which is now a macro. Since the only one caller that uses nowait = true now passes a callback anyway, the RangeVarGetRelid() macro defaults nowait as well. The callback can also be used for supplemental locking - for example, REINDEX INDEX needs to acquire the table lock before the index lock to reduce deadlock possibilities. There's a lot more work to be done here to fix all the cases where this can be a problem, but this commit provides the general infrastructure and fixes the following specific cases: REINDEX INDEX, REINDEX TABLE, LOCK TABLE, and and DROP TABLE/INDEX/SEQUENCE/VIEW/FOREIGN TABLE. Per discussion with Noah Misch and Alvaro Herrera.
2011-11-30 16:12:27 +01:00
/*
* Before acquiring a table lock, check whether we have sufficient rights.
* In the case of DROP INDEX, also try to lock the table before the index.
*/
static void
RangeVarCallbackForDropRelation(const RangeVar *rel, Oid relOid, Oid oldRelOid,
void *arg)
{
HeapTuple tuple;
struct DropRelationCallbackState *state;
char relkind;
Form_pg_class classform;
LOCKMODE heap_lockmode;
Improve table locking behavior in the face of current DDL. In the previous coding, callers were faced with an awkward choice: look up the name, do permissions checks, and then lock the table; or look up the name, lock the table, and then do permissions checks. The first choice was wrong because the results of the name lookup and permissions checks might be out-of-date by the time the table lock was acquired, while the second allowed a user with no privileges to interfere with access to a table by users who do have privileges (e.g. if a malicious backend queues up for an AccessExclusiveLock on a table on which AccessShareLock is already held, further attempts to access the table will be blocked until the AccessExclusiveLock is obtained and the malicious backend's transaction rolls back). To fix, allow callers of RangeVarGetRelid() to pass a callback which gets executed after performing the name lookup but before acquiring the relation lock. If the name lookup is retried (because invalidation messages are received), the callback will be re-executed as well, so we get the best of both worlds. RangeVarGetRelid() is renamed to RangeVarGetRelidExtended(); callers not wishing to supply a callback can continue to invoke it as RangeVarGetRelid(), which is now a macro. Since the only one caller that uses nowait = true now passes a callback anyway, the RangeVarGetRelid() macro defaults nowait as well. The callback can also be used for supplemental locking - for example, REINDEX INDEX needs to acquire the table lock before the index lock to reduce deadlock possibilities. There's a lot more work to be done here to fix all the cases where this can be a problem, but this commit provides the general infrastructure and fixes the following specific cases: REINDEX INDEX, REINDEX TABLE, LOCK TABLE, and and DROP TABLE/INDEX/SEQUENCE/VIEW/FOREIGN TABLE. Per discussion with Noah Misch and Alvaro Herrera.
2011-11-30 16:12:27 +01:00
state = (struct DropRelationCallbackState *) arg;
relkind = state->relkind;
heap_lockmode = state->concurrent ?
ShareUpdateExclusiveLock : AccessExclusiveLock;
Improve table locking behavior in the face of current DDL. In the previous coding, callers were faced with an awkward choice: look up the name, do permissions checks, and then lock the table; or look up the name, lock the table, and then do permissions checks. The first choice was wrong because the results of the name lookup and permissions checks might be out-of-date by the time the table lock was acquired, while the second allowed a user with no privileges to interfere with access to a table by users who do have privileges (e.g. if a malicious backend queues up for an AccessExclusiveLock on a table on which AccessShareLock is already held, further attempts to access the table will be blocked until the AccessExclusiveLock is obtained and the malicious backend's transaction rolls back). To fix, allow callers of RangeVarGetRelid() to pass a callback which gets executed after performing the name lookup but before acquiring the relation lock. If the name lookup is retried (because invalidation messages are received), the callback will be re-executed as well, so we get the best of both worlds. RangeVarGetRelid() is renamed to RangeVarGetRelidExtended(); callers not wishing to supply a callback can continue to invoke it as RangeVarGetRelid(), which is now a macro. Since the only one caller that uses nowait = true now passes a callback anyway, the RangeVarGetRelid() macro defaults nowait as well. The callback can also be used for supplemental locking - for example, REINDEX INDEX needs to acquire the table lock before the index lock to reduce deadlock possibilities. There's a lot more work to be done here to fix all the cases where this can be a problem, but this commit provides the general infrastructure and fixes the following specific cases: REINDEX INDEX, REINDEX TABLE, LOCK TABLE, and and DROP TABLE/INDEX/SEQUENCE/VIEW/FOREIGN TABLE. Per discussion with Noah Misch and Alvaro Herrera.
2011-11-30 16:12:27 +01:00
/*
* If we previously locked some other index's heap, and the name we're
* looking up no longer refers to that relation, release the now-useless
* lock.
*/
if (relOid != oldRelOid && OidIsValid(state->heapOid))
{
UnlockRelationOid(state->heapOid, heap_lockmode);
Improve table locking behavior in the face of current DDL. In the previous coding, callers were faced with an awkward choice: look up the name, do permissions checks, and then lock the table; or look up the name, lock the table, and then do permissions checks. The first choice was wrong because the results of the name lookup and permissions checks might be out-of-date by the time the table lock was acquired, while the second allowed a user with no privileges to interfere with access to a table by users who do have privileges (e.g. if a malicious backend queues up for an AccessExclusiveLock on a table on which AccessShareLock is already held, further attempts to access the table will be blocked until the AccessExclusiveLock is obtained and the malicious backend's transaction rolls back). To fix, allow callers of RangeVarGetRelid() to pass a callback which gets executed after performing the name lookup but before acquiring the relation lock. If the name lookup is retried (because invalidation messages are received), the callback will be re-executed as well, so we get the best of both worlds. RangeVarGetRelid() is renamed to RangeVarGetRelidExtended(); callers not wishing to supply a callback can continue to invoke it as RangeVarGetRelid(), which is now a macro. Since the only one caller that uses nowait = true now passes a callback anyway, the RangeVarGetRelid() macro defaults nowait as well. The callback can also be used for supplemental locking - for example, REINDEX INDEX needs to acquire the table lock before the index lock to reduce deadlock possibilities. There's a lot more work to be done here to fix all the cases where this can be a problem, but this commit provides the general infrastructure and fixes the following specific cases: REINDEX INDEX, REINDEX TABLE, LOCK TABLE, and and DROP TABLE/INDEX/SEQUENCE/VIEW/FOREIGN TABLE. Per discussion with Noah Misch and Alvaro Herrera.
2011-11-30 16:12:27 +01:00
state->heapOid = InvalidOid;
}
/* Didn't find a relation, so no need for locking or permission checks. */
Improve table locking behavior in the face of current DDL. In the previous coding, callers were faced with an awkward choice: look up the name, do permissions checks, and then lock the table; or look up the name, lock the table, and then do permissions checks. The first choice was wrong because the results of the name lookup and permissions checks might be out-of-date by the time the table lock was acquired, while the second allowed a user with no privileges to interfere with access to a table by users who do have privileges (e.g. if a malicious backend queues up for an AccessExclusiveLock on a table on which AccessShareLock is already held, further attempts to access the table will be blocked until the AccessExclusiveLock is obtained and the malicious backend's transaction rolls back). To fix, allow callers of RangeVarGetRelid() to pass a callback which gets executed after performing the name lookup but before acquiring the relation lock. If the name lookup is retried (because invalidation messages are received), the callback will be re-executed as well, so we get the best of both worlds. RangeVarGetRelid() is renamed to RangeVarGetRelidExtended(); callers not wishing to supply a callback can continue to invoke it as RangeVarGetRelid(), which is now a macro. Since the only one caller that uses nowait = true now passes a callback anyway, the RangeVarGetRelid() macro defaults nowait as well. The callback can also be used for supplemental locking - for example, REINDEX INDEX needs to acquire the table lock before the index lock to reduce deadlock possibilities. There's a lot more work to be done here to fix all the cases where this can be a problem, but this commit provides the general infrastructure and fixes the following specific cases: REINDEX INDEX, REINDEX TABLE, LOCK TABLE, and and DROP TABLE/INDEX/SEQUENCE/VIEW/FOREIGN TABLE. Per discussion with Noah Misch and Alvaro Herrera.
2011-11-30 16:12:27 +01:00
if (!OidIsValid(relOid))
return;
tuple = SearchSysCache1(RELOID, ObjectIdGetDatum(relOid));
if (!HeapTupleIsValid(tuple))
return; /* concurrently dropped, so nothing to do */
classform = (Form_pg_class) GETSTRUCT(tuple);
if (classform->relkind != relkind)
DropErrorMsgWrongType(rel->relname, classform->relkind, relkind);
/* Allow DROP to either table owner or schema owner */
if (!pg_class_ownercheck(relOid, GetUserId()) &&
!pg_namespace_ownercheck(classform->relnamespace, GetUserId()))
aclcheck_error(ACLCHECK_NOT_OWNER, ACL_KIND_CLASS,
rel->relname);
if (!allowSystemTableMods && IsSystemClass(classform))
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
errmsg("permission denied: \"%s\" is a system catalog",
rel->relname)));
ReleaseSysCache(tuple);
/*
* In DROP INDEX, attempt to acquire lock on the parent table before
* locking the index. index_drop() will need this anyway, and since
* regular queries lock tables before their indexes, we risk deadlock if
* we do it the other way around. No error if we don't find a pg_index
Fix assorted bugs in CREATE/DROP INDEX CONCURRENTLY. Commit 8cb53654dbdb4c386369eb988062d0bbb6de725e, which introduced DROP INDEX CONCURRENTLY, managed to break CREATE INDEX CONCURRENTLY via a poor choice of catalog state representation. The pg_index state for an index that's reached the final pre-drop stage was the same as the state for an index just created by CREATE INDEX CONCURRENTLY. This meant that the (necessary) change to make RelationGetIndexList ignore about-to-die indexes also made it ignore freshly-created indexes; which is catastrophic because the latter do need to be considered in HOT-safety decisions. Failure to do so leads to incorrect index entries and subsequently wrong results from queries depending on the concurrently-created index. To fix, add an additional boolean column "indislive" to pg_index, so that the freshly-created and about-to-die states can be distinguished. (This change obviously is only possible in HEAD. This patch will need to be back-patched, but in 9.2 we'll use a kluge consisting of overloading the formerly-impossible state of indisvalid = true and indisready = false.) In addition, change CREATE/DROP INDEX CONCURRENTLY so that the pg_index flag changes they make without exclusive lock on the index are made via heap_inplace_update() rather than a normal transactional update. The latter is not very safe because moving the pg_index tuple could result in concurrent SnapshotNow scans finding it twice or not at all, thus possibly resulting in index corruption. This is a pre-existing bug in CREATE INDEX CONCURRENTLY, which was copied into the DROP code. In addition, fix various places in the code that ought to check to make sure that the indexes they are manipulating are valid and/or ready as appropriate. These represent bugs that have existed since 8.2, since a failed CREATE INDEX CONCURRENTLY could leave a corrupt or invalid index behind, and we ought not try to do anything that might fail with such an index. Also fix RelationReloadIndexInfo to ensure it copies all the pg_index columns that are allowed to change after initial creation. Previously we could have been left with stale values of some fields in an index relcache entry. It's not clear whether this actually had any user-visible consequences, but it's at least a bug waiting to happen. In addition, do some code and docs review for DROP INDEX CONCURRENTLY; some cosmetic code cleanup but mostly addition and revision of comments. This will need to be back-patched, but in a noticeably different form, so I'm committing it to HEAD before working on the back-patch. Problem reported by Amit Kapila, diagnosis by Pavan Deolassee, fix by Tom Lane and Andres Freund.
2012-11-29 03:25:27 +01:00
* entry, though --- the relation may have been dropped.
Improve table locking behavior in the face of current DDL. In the previous coding, callers were faced with an awkward choice: look up the name, do permissions checks, and then lock the table; or look up the name, lock the table, and then do permissions checks. The first choice was wrong because the results of the name lookup and permissions checks might be out-of-date by the time the table lock was acquired, while the second allowed a user with no privileges to interfere with access to a table by users who do have privileges (e.g. if a malicious backend queues up for an AccessExclusiveLock on a table on which AccessShareLock is already held, further attempts to access the table will be blocked until the AccessExclusiveLock is obtained and the malicious backend's transaction rolls back). To fix, allow callers of RangeVarGetRelid() to pass a callback which gets executed after performing the name lookup but before acquiring the relation lock. If the name lookup is retried (because invalidation messages are received), the callback will be re-executed as well, so we get the best of both worlds. RangeVarGetRelid() is renamed to RangeVarGetRelidExtended(); callers not wishing to supply a callback can continue to invoke it as RangeVarGetRelid(), which is now a macro. Since the only one caller that uses nowait = true now passes a callback anyway, the RangeVarGetRelid() macro defaults nowait as well. The callback can also be used for supplemental locking - for example, REINDEX INDEX needs to acquire the table lock before the index lock to reduce deadlock possibilities. There's a lot more work to be done here to fix all the cases where this can be a problem, but this commit provides the general infrastructure and fixes the following specific cases: REINDEX INDEX, REINDEX TABLE, LOCK TABLE, and and DROP TABLE/INDEX/SEQUENCE/VIEW/FOREIGN TABLE. Per discussion with Noah Misch and Alvaro Herrera.
2011-11-30 16:12:27 +01:00
*/
if (relkind == RELKIND_INDEX && relOid != oldRelOid)
{
state->heapOid = IndexGetRelation(relOid, true);
if (OidIsValid(state->heapOid))
LockRelationOid(state->heapOid, heap_lockmode);
Improve table locking behavior in the face of current DDL. In the previous coding, callers were faced with an awkward choice: look up the name, do permissions checks, and then lock the table; or look up the name, lock the table, and then do permissions checks. The first choice was wrong because the results of the name lookup and permissions checks might be out-of-date by the time the table lock was acquired, while the second allowed a user with no privileges to interfere with access to a table by users who do have privileges (e.g. if a malicious backend queues up for an AccessExclusiveLock on a table on which AccessShareLock is already held, further attempts to access the table will be blocked until the AccessExclusiveLock is obtained and the malicious backend's transaction rolls back). To fix, allow callers of RangeVarGetRelid() to pass a callback which gets executed after performing the name lookup but before acquiring the relation lock. If the name lookup is retried (because invalidation messages are received), the callback will be re-executed as well, so we get the best of both worlds. RangeVarGetRelid() is renamed to RangeVarGetRelidExtended(); callers not wishing to supply a callback can continue to invoke it as RangeVarGetRelid(), which is now a macro. Since the only one caller that uses nowait = true now passes a callback anyway, the RangeVarGetRelid() macro defaults nowait as well. The callback can also be used for supplemental locking - for example, REINDEX INDEX needs to acquire the table lock before the index lock to reduce deadlock possibilities. There's a lot more work to be done here to fix all the cases where this can be a problem, but this commit provides the general infrastructure and fixes the following specific cases: REINDEX INDEX, REINDEX TABLE, LOCK TABLE, and and DROP TABLE/INDEX/SEQUENCE/VIEW/FOREIGN TABLE. Per discussion with Noah Misch and Alvaro Herrera.
2011-11-30 16:12:27 +01:00
}
}
/*
* ExecuteTruncate
2005-10-15 04:49:52 +02:00
* Executes a TRUNCATE command.
*
* This is a multi-relation truncate. We first open and grab exclusive
* lock on all relations involved, checking permissions and otherwise
* verifying that the relation is OK for truncation. In CASCADE mode,
* relations having FK references to the targeted relations are automatically
* added to the group; in RESTRICT mode, we check that all FK references are
* internal to the group that's being truncated. Finally all the relations
* are truncated and reindexed.
*/
void
ExecuteTruncate(TruncateStmt *stmt)
{
2005-10-15 04:49:52 +02:00
List *rels = NIL;
List *relids = NIL;
List *seq_relids = NIL;
EState *estate;
ResultRelInfo *resultRelInfos;
ResultRelInfo *resultRelInfo;
SubTransactionId mySubid;
2005-10-15 04:49:52 +02:00
ListCell *cell;
/*
* Open, exclusive-lock, and check all the explicitly-specified relations
*/
foreach(cell, stmt->relations)
{
RangeVar *rv = lfirst(cell);
Relation rel;
bool recurse = interpretInhOption(rv->inhOpt);
Oid myrelid;
rel = heap_openrv(rv, AccessExclusiveLock);
myrelid = RelationGetRelid(rel);
/* don't throw error for "TRUNCATE foo, foo" */
if (list_member_oid(relids, myrelid))
{
heap_close(rel, AccessExclusiveLock);
continue;
}
truncate_check_rel(rel);
rels = lappend(rels, rel);
relids = lappend_oid(relids, myrelid);
if (recurse)
{
ListCell *child;
List *children;
children = find_all_inheritors(myrelid, AccessExclusiveLock, NULL);
foreach(child, children)
{
Oid childrelid = lfirst_oid(child);
if (list_member_oid(relids, childrelid))
continue;
/* find_all_inheritors already got lock */
rel = heap_open(childrelid, NoLock);
truncate_check_rel(rel);
rels = lappend(rels, rel);
relids = lappend_oid(relids, childrelid);
}
}
}
/*
2006-10-04 02:30:14 +02:00
* In CASCADE mode, suck in all referencing relations as well. This
* requires multiple iterations to find indirectly-dependent relations. At
* each phase, we need to exclusive-lock new rels before looking for their
* dependencies, else we might miss something. Also, we check each rel as
* soon as we open it, to avoid a faux pas such as holding lock for a long
* time on a rel we have no permissions for.
*/
if (stmt->behavior == DROP_CASCADE)
{
for (;;)
{
2006-10-04 02:30:14 +02:00
List *newrelids;
newrelids = heap_truncate_find_FKs(relids);
if (newrelids == NIL)
break; /* nothing else to add */
foreach(cell, newrelids)
{
2006-10-04 02:30:14 +02:00
Oid relid = lfirst_oid(cell);
Relation rel;
rel = heap_open(relid, AccessExclusiveLock);
ereport(NOTICE,
(errmsg("truncate cascades to table \"%s\"",
RelationGetRelationName(rel))));
truncate_check_rel(rel);
rels = lappend(rels, rel);
relids = lappend_oid(relids, relid);
}
}
}
2002-11-23 05:05:52 +01:00
/*
* Check foreign key references. In CASCADE mode, this should be
2006-10-04 02:30:14 +02:00
* unnecessary since we just pulled in all the references; but as a
* cross-check, do it anyway if in an Assert-enabled build.
2002-11-23 05:05:52 +01:00
*/
#ifdef USE_ASSERT_CHECKING
heap_truncate_check_FKs(rels, false);
#else
if (stmt->behavior == DROP_RESTRICT)
heap_truncate_check_FKs(rels, false);
#endif
/*
* If we are asked to restart sequences, find all the sequences, lock them
2010-11-17 22:42:18 +01:00
* (we need AccessExclusiveLock for ResetSequence), and check permissions.
* We want to do this early since it's pointless to do all the truncation
* work only to fail on sequence permissions.
*/
if (stmt->restart_seqs)
{
foreach(cell, rels)
{
Relation rel = (Relation) lfirst(cell);
List *seqlist = getOwnedSequences(RelationGetRelid(rel));
ListCell *seqcell;
foreach(seqcell, seqlist)
{
Oid seq_relid = lfirst_oid(seqcell);
Relation seq_rel;
2010-11-17 22:42:18 +01:00
seq_rel = relation_open(seq_relid, AccessExclusiveLock);
/* This check must match AlterSequence! */
if (!pg_class_ownercheck(seq_relid, GetUserId()))
aclcheck_error(ACLCHECK_NOT_OWNER, ACL_KIND_CLASS,
RelationGetRelationName(seq_rel));
seq_relids = lappend_oid(seq_relids, seq_relid);
relation_close(seq_rel, NoLock);
}
}
}
/* Prepare to catch AFTER triggers. */
AfterTriggerBeginQuery();
/*
* To fire triggers, we'll need an EState as well as a ResultRelInfo for
* each relation. We don't need to call ExecOpenIndices, though.
*/
estate = CreateExecutorState();
resultRelInfos = (ResultRelInfo *)
palloc(list_length(rels) * sizeof(ResultRelInfo));
resultRelInfo = resultRelInfos;
foreach(cell, rels)
{
Relation rel = (Relation) lfirst(cell);
InitResultRelInfo(resultRelInfo,
rel,
0, /* dummy rangetable index */
0);
resultRelInfo++;
}
estate->es_result_relations = resultRelInfos;
estate->es_num_result_relations = list_length(rels);
/*
* Process all BEFORE STATEMENT TRUNCATE triggers before we begin
* truncating (this is because one of them might throw an error). Also, if
* we were to allow them to prevent statement execution, that would need
* to be handled here.
*/
resultRelInfo = resultRelInfos;
foreach(cell, rels)
{
estate->es_result_relation_info = resultRelInfo;
ExecBSTruncateTriggers(estate, resultRelInfo);
resultRelInfo++;
}
/*
* OK, truncate each table.
*/
mySubid = GetCurrentSubTransactionId();
foreach(cell, rels)
{
Relation rel = (Relation) lfirst(cell);
/*
2010-02-26 03:01:40 +01:00
* Normally, we need a transaction-safe truncation here. However, if
* the table was either created in the current (sub)transaction or has
* a new relfilenode in the current (sub)transaction, then we can just
* truncate it in-place, because a rollback would cause the whole
* table or the current physical file to be thrown away anyway.
*/
if (rel->rd_createSubid == mySubid ||
rel->rd_newRelfilenodeSubid == mySubid)
{
/* Immediate, non-rollbackable truncation is OK */
heap_truncate_one_rel(rel);
}
else
{
Oid heap_relid;
Oid toast_relid;
MultiXactId minmulti;
/*
* This effectively deletes all rows in the table, and may be done
* in a serializable transaction. In that case we must record a
* rw-conflict in to this transaction from each transaction
* holding a predicate lock on the table.
*/
CheckTableForSerializableConflictIn(rel);
Improve concurrency of foreign key locking This patch introduces two additional lock modes for tuples: "SELECT FOR KEY SHARE" and "SELECT FOR NO KEY UPDATE". These don't block each other, in contrast with already existing "SELECT FOR SHARE" and "SELECT FOR UPDATE". UPDATE commands that do not modify the values stored in the columns that are part of the key of the tuple now grab a SELECT FOR NO KEY UPDATE lock on the tuple, allowing them to proceed concurrently with tuple locks of the FOR KEY SHARE variety. Foreign key triggers now use FOR KEY SHARE instead of FOR SHARE; this means the concurrency improvement applies to them, which is the whole point of this patch. The added tuple lock semantics require some rejiggering of the multixact module, so that the locking level that each transaction is holding can be stored alongside its Xid. Also, multixacts now need to persist across server restarts and crashes, because they can now represent not only tuple locks, but also tuple updates. This means we need more careful tracking of lifetime of pg_multixact SLRU files; since they now persist longer, we require more infrastructure to figure out when they can be removed. pg_upgrade also needs to be careful to copy pg_multixact files over from the old server to the new, or at least part of multixact.c state, depending on the versions of the old and new servers. Tuple time qualification rules (HeapTupleSatisfies routines) need to be careful not to consider tuples with the "is multi" infomask bit set as being only locked; they might need to look up MultiXact values (i.e. possibly do pg_multixact I/O) to find out the Xid that updated a tuple, whereas they previously were assured to only use information readily available from the tuple header. This is considered acceptable, because the extra I/O would involve cases that would previously cause some commands to block waiting for concurrent transactions to finish. Another important change is the fact that locking tuples that have previously been updated causes the future versions to be marked as locked, too; this is essential for correctness of foreign key checks. This causes additional WAL-logging, also (there was previously a single WAL record for a locked tuple; now there are as many as updated copies of the tuple there exist.) With all this in place, contention related to tuples being checked by foreign key rules should be much reduced. As a bonus, the old behavior that a subtransaction grabbing a stronger tuple lock than the parent (sub)transaction held on a given tuple and later aborting caused the weaker lock to be lost, has been fixed. Many new spec files were added for isolation tester framework, to ensure overall behavior is sane. There's probably room for several more tests. There were several reviewers of this patch; in particular, Noah Misch and Andres Freund spent considerable time in it. Original idea for the patch came from Simon Riggs, after a problem report by Joel Jacobson. Most code is from me, with contributions from Marti Raudsepp, Alexander Shulgin, Noah Misch and Andres Freund. This patch was discussed in several pgsql-hackers threads; the most important start at the following message-ids: AANLkTimo9XVcEzfiBR-ut3KVNDkjm2Vxh+t8kAmWjPuv@mail.gmail.com 1290721684-sup-3951@alvh.no-ip.org 1294953201-sup-2099@alvh.no-ip.org 1320343602-sup-2290@alvh.no-ip.org 1339690386-sup-8927@alvh.no-ip.org 4FE5FF020200002500048A3D@gw.wicourts.gov 4FEAB90A0200002500048B7D@gw.wicourts.gov
2013-01-23 16:04:59 +01:00
minmulti = GetOldestMultiXactId();
/*
* Need the full transaction-safe pushups.
*
* Create a new empty storage file for the relation, and assign it
* as the relfilenode value. The old storage file is scheduled for
* deletion at commit.
*/
Improve concurrency of foreign key locking This patch introduces two additional lock modes for tuples: "SELECT FOR KEY SHARE" and "SELECT FOR NO KEY UPDATE". These don't block each other, in contrast with already existing "SELECT FOR SHARE" and "SELECT FOR UPDATE". UPDATE commands that do not modify the values stored in the columns that are part of the key of the tuple now grab a SELECT FOR NO KEY UPDATE lock on the tuple, allowing them to proceed concurrently with tuple locks of the FOR KEY SHARE variety. Foreign key triggers now use FOR KEY SHARE instead of FOR SHARE; this means the concurrency improvement applies to them, which is the whole point of this patch. The added tuple lock semantics require some rejiggering of the multixact module, so that the locking level that each transaction is holding can be stored alongside its Xid. Also, multixacts now need to persist across server restarts and crashes, because they can now represent not only tuple locks, but also tuple updates. This means we need more careful tracking of lifetime of pg_multixact SLRU files; since they now persist longer, we require more infrastructure to figure out when they can be removed. pg_upgrade also needs to be careful to copy pg_multixact files over from the old server to the new, or at least part of multixact.c state, depending on the versions of the old and new servers. Tuple time qualification rules (HeapTupleSatisfies routines) need to be careful not to consider tuples with the "is multi" infomask bit set as being only locked; they might need to look up MultiXact values (i.e. possibly do pg_multixact I/O) to find out the Xid that updated a tuple, whereas they previously were assured to only use information readily available from the tuple header. This is considered acceptable, because the extra I/O would involve cases that would previously cause some commands to block waiting for concurrent transactions to finish. Another important change is the fact that locking tuples that have previously been updated causes the future versions to be marked as locked, too; this is essential for correctness of foreign key checks. This causes additional WAL-logging, also (there was previously a single WAL record for a locked tuple; now there are as many as updated copies of the tuple there exist.) With all this in place, contention related to tuples being checked by foreign key rules should be much reduced. As a bonus, the old behavior that a subtransaction grabbing a stronger tuple lock than the parent (sub)transaction held on a given tuple and later aborting caused the weaker lock to be lost, has been fixed. Many new spec files were added for isolation tester framework, to ensure overall behavior is sane. There's probably room for several more tests. There were several reviewers of this patch; in particular, Noah Misch and Andres Freund spent considerable time in it. Original idea for the patch came from Simon Riggs, after a problem report by Joel Jacobson. Most code is from me, with contributions from Marti Raudsepp, Alexander Shulgin, Noah Misch and Andres Freund. This patch was discussed in several pgsql-hackers threads; the most important start at the following message-ids: AANLkTimo9XVcEzfiBR-ut3KVNDkjm2Vxh+t8kAmWjPuv@mail.gmail.com 1290721684-sup-3951@alvh.no-ip.org 1294953201-sup-2099@alvh.no-ip.org 1320343602-sup-2290@alvh.no-ip.org 1339690386-sup-8927@alvh.no-ip.org 4FE5FF020200002500048A3D@gw.wicourts.gov 4FEAB90A0200002500048B7D@gw.wicourts.gov
2013-01-23 16:04:59 +01:00
RelationSetNewRelfilenode(rel, RecentXmin, minmulti);
if (rel->rd_rel->relpersistence == RELPERSISTENCE_UNLOGGED)
heap_create_init_fork(rel);
heap_relid = RelationGetRelid(rel);
toast_relid = rel->rd_rel->reltoastrelid;
/*
* The same for the toast table, if any.
*/
if (OidIsValid(toast_relid))
{
rel = relation_open(toast_relid, AccessExclusiveLock);
Improve concurrency of foreign key locking This patch introduces two additional lock modes for tuples: "SELECT FOR KEY SHARE" and "SELECT FOR NO KEY UPDATE". These don't block each other, in contrast with already existing "SELECT FOR SHARE" and "SELECT FOR UPDATE". UPDATE commands that do not modify the values stored in the columns that are part of the key of the tuple now grab a SELECT FOR NO KEY UPDATE lock on the tuple, allowing them to proceed concurrently with tuple locks of the FOR KEY SHARE variety. Foreign key triggers now use FOR KEY SHARE instead of FOR SHARE; this means the concurrency improvement applies to them, which is the whole point of this patch. The added tuple lock semantics require some rejiggering of the multixact module, so that the locking level that each transaction is holding can be stored alongside its Xid. Also, multixacts now need to persist across server restarts and crashes, because they can now represent not only tuple locks, but also tuple updates. This means we need more careful tracking of lifetime of pg_multixact SLRU files; since they now persist longer, we require more infrastructure to figure out when they can be removed. pg_upgrade also needs to be careful to copy pg_multixact files over from the old server to the new, or at least part of multixact.c state, depending on the versions of the old and new servers. Tuple time qualification rules (HeapTupleSatisfies routines) need to be careful not to consider tuples with the "is multi" infomask bit set as being only locked; they might need to look up MultiXact values (i.e. possibly do pg_multixact I/O) to find out the Xid that updated a tuple, whereas they previously were assured to only use information readily available from the tuple header. This is considered acceptable, because the extra I/O would involve cases that would previously cause some commands to block waiting for concurrent transactions to finish. Another important change is the fact that locking tuples that have previously been updated causes the future versions to be marked as locked, too; this is essential for correctness of foreign key checks. This causes additional WAL-logging, also (there was previously a single WAL record for a locked tuple; now there are as many as updated copies of the tuple there exist.) With all this in place, contention related to tuples being checked by foreign key rules should be much reduced. As a bonus, the old behavior that a subtransaction grabbing a stronger tuple lock than the parent (sub)transaction held on a given tuple and later aborting caused the weaker lock to be lost, has been fixed. Many new spec files were added for isolation tester framework, to ensure overall behavior is sane. There's probably room for several more tests. There were several reviewers of this patch; in particular, Noah Misch and Andres Freund spent considerable time in it. Original idea for the patch came from Simon Riggs, after a problem report by Joel Jacobson. Most code is from me, with contributions from Marti Raudsepp, Alexander Shulgin, Noah Misch and Andres Freund. This patch was discussed in several pgsql-hackers threads; the most important start at the following message-ids: AANLkTimo9XVcEzfiBR-ut3KVNDkjm2Vxh+t8kAmWjPuv@mail.gmail.com 1290721684-sup-3951@alvh.no-ip.org 1294953201-sup-2099@alvh.no-ip.org 1320343602-sup-2290@alvh.no-ip.org 1339690386-sup-8927@alvh.no-ip.org 4FE5FF020200002500048A3D@gw.wicourts.gov 4FEAB90A0200002500048B7D@gw.wicourts.gov
2013-01-23 16:04:59 +01:00
RelationSetNewRelfilenode(rel, RecentXmin, minmulti);
if (rel->rd_rel->relpersistence == RELPERSISTENCE_UNLOGGED)
heap_create_init_fork(rel);
heap_close(rel, NoLock);
}
/*
* Reconstruct the indexes to match, and we're done.
*/
reindex_relation(heap_relid, REINDEX_REL_PROCESS_TOAST);
}
}
2010-11-17 22:42:18 +01:00
/*
* Restart owned sequences if we were asked to.
*/
foreach(cell, seq_relids)
{
Oid seq_relid = lfirst_oid(cell);
ResetSequence(seq_relid);
}
/*
* Process all AFTER STATEMENT TRUNCATE triggers.
*/
resultRelInfo = resultRelInfos;
foreach(cell, rels)
{
estate->es_result_relation_info = resultRelInfo;
ExecASTruncateTriggers(estate, resultRelInfo);
resultRelInfo++;
}
/* Handle queued AFTER triggers */
AfterTriggerEndQuery(estate);
/* We can clean up the EState now */
FreeExecutorState(estate);
/* And close the rels (can't do this while EState still holds refs) */
foreach(cell, rels)
{
Relation rel = (Relation) lfirst(cell);
heap_close(rel, NoLock);
}
}
/*
2006-10-04 02:30:14 +02:00
* Check that a given rel is safe to truncate. Subroutine for ExecuteTruncate
*/
static void
truncate_check_rel(Relation rel)
{
AclResult aclresult;
/* Only allow truncate on regular tables */
if (rel->rd_rel->relkind != RELKIND_RELATION)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("\"%s\" is not a table",
RelationGetRelationName(rel))));
/* Permissions checks */
aclresult = pg_class_aclcheck(RelationGetRelid(rel), GetUserId(),
ACL_TRUNCATE);
if (aclresult != ACLCHECK_OK)
aclcheck_error(aclresult, ACL_KIND_CLASS,
RelationGetRelationName(rel));
if (!allowSystemTableMods && IsSystemRelation(rel))
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
errmsg("permission denied: \"%s\" is a system catalog",
RelationGetRelationName(rel))));
/*
2006-10-04 02:30:14 +02:00
* Don't allow truncate on temp tables of other backends ... their local
* buffer manager is not going to cope.
*/
if (RELATION_IS_OTHER_TEMP(rel))
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
2006-10-04 02:30:14 +02:00
errmsg("cannot truncate temporary tables of other sessions")));
/*
* Also check for active uses of the relation in the current transaction,
* including open scans and pending AFTER trigger events.
*/
CheckTableNotInUse(rel, "TRUNCATE");
}
/*
* storage_name
2010-02-26 03:01:40 +01:00
* returns the name corresponding to a typstorage/attstorage enum value
*/
static const char *
storage_name(char c)
{
switch (c)
{
case 'p':
return "PLAIN";
case 'm':
return "MAIN";
case 'x':
return "EXTENDED";
case 'e':
return "EXTERNAL";
default:
return "???";
}
}
/*----------
* MergeAttributes
* Returns new schema given initial schema and superclasses.
*
* Input arguments:
* 'schema' is the column/attribute definition for the table. (It's a list
* of ColumnDef's.) It is destructively changed.
* 'supers' is a list of names (as RangeVar nodes) of parent relations.
* 'relpersistence' is a persistence type of the table.
*
* Output arguments:
* 'supOids' receives a list of the OIDs of the parent relations.
* 'supconstr' receives a list of constraints belonging to the parents,
* updated as necessary to be valid for the child.
* 'supOidCount' is set to the number of parents that have OID columns.
*
* Return value:
* Completed schema list.
*
* Notes:
* The order in which the attributes are inherited is very important.
* Intuitively, the inherited attributes should come first. If a table
* inherits from multiple parents, the order of those attributes are
* according to the order of the parents specified in CREATE TABLE.
*
* Here's an example:
*
* create table person (name text, age int4, location point);
* create table emp (salary int4, manager text) inherits(person);
* create table student (gpa float8) inherits (person);
* create table stud_emp (percent int4) inherits (emp, student);
*
* The order of the attributes of stud_emp is:
*
* person {1:name, 2:age, 3:location}
* / \
* {6:gpa} student emp {4:salary, 5:manager}
* \ /
* stud_emp {7:percent}
*
* If the same attribute name appears multiple times, then it appears
* in the result table in the proper location for its first appearance.
*
* Constraints (including NOT NULL constraints) for the child table
* are the union of all relevant constraints, from both the child schema
* and parent tables.
*
* The default value for a child column is defined as:
* (1) If the child schema specifies a default, that value is used.
* (2) If neither the child nor any parent specifies a default, then
* the column will not have a default.
* (3) If conflicting defaults are inherited from different parents
* (and not overridden by the child), an error is raised.
* (4) Otherwise the inherited default is used.
* Rule (3) is new in Postgres 7.1; in earlier releases you got a
* rather arbitrary choice of which parent default to use.
*----------
*/
static List *
MergeAttributes(List *schema, List *supers, char relpersistence,
List **supOids, List **supconstr, int *supOidCount)
{
ListCell *entry;
List *inhSchema = NIL;
List *parentOids = NIL;
List *constraints = NIL;
int parentsWithOids = 0;
bool have_bogus_defaults = false;
int child_attno;
2010-02-26 03:01:40 +01:00
static Node bogus_marker = {0}; /* marks conflicting defaults */
/*
2005-10-15 04:49:52 +02:00
* Check for and reject tables with too many columns. We perform this
* check relatively early for two reasons: (a) we don't run the risk of
* overflowing an AttrNumber in subsequent code (b) an O(n^2) algorithm is
* okay if we're processing <= 1600 columns, but could take minutes to
* execute if the user attempts to create a table with hundreds of
* thousands of columns.
*
2005-10-15 04:49:52 +02:00
* Note that we also need to check that any we do not exceed this figure
* after including columns from inherited relations.
*/
if (list_length(schema) > MaxHeapAttributeNumber)
ereport(ERROR,
(errcode(ERRCODE_TOO_MANY_COLUMNS),
errmsg("tables can have at most %d columns",
MaxHeapAttributeNumber)));
/*
* Check for duplicate names in the explicit list of attributes.
*
2005-10-15 04:49:52 +02:00
* Although we might consider merging such entries in the same way that we
* handle name conflicts for inherited attributes, it seems to make more
* sense to assume such conflicts are errors.
*/
foreach(entry, schema)
{
ColumnDef *coldef = lfirst(entry);
ListCell *rest = lnext(entry);
ListCell *prev = entry;
if (coldef->typeName == NULL)
2010-02-26 03:01:40 +01:00
/*
2010-02-26 03:01:40 +01:00
* Typed table column option that does not belong to a column from
* the type. This works because the columns from the type come
* first in the list.
*/
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_COLUMN),
errmsg("column \"%s\" does not exist",
coldef->colname)));
while (rest != NULL)
{
ColumnDef *restdef = lfirst(rest);
2010-02-26 03:01:40 +01:00
ListCell *next = lnext(rest); /* need to save it in case we
* delete it */
if (strcmp(coldef->colname, restdef->colname) == 0)
{
if (coldef->is_from_type)
{
2010-02-26 03:01:40 +01:00
/*
* merge the column options into the column from the type
*/
coldef->is_not_null = restdef->is_not_null;
coldef->raw_default = restdef->raw_default;
coldef->cooked_default = restdef->cooked_default;
coldef->constraints = restdef->constraints;
coldef->is_from_type = false;
list_delete_cell(schema, rest, prev);
}
else
ereport(ERROR,
(errcode(ERRCODE_DUPLICATE_COLUMN),
errmsg("column \"%s\" specified more than once",
coldef->colname)));
}
prev = rest;
rest = next;
}
}
/*
2005-10-15 04:49:52 +02:00
* Scan the parents left-to-right, and merge their attributes to form a
* list of inherited attributes (inhSchema). Also check to see if we need
* to inherit an OID column.
*/
child_attno = 0;
foreach(entry, supers)
{
RangeVar *parent = (RangeVar *) lfirst(entry);
Relation relation;
TupleDesc tupleDesc;
TupleConstr *constr;
AttrNumber *newattno;
AttrNumber parent_attno;
/*
* A self-exclusive lock is needed here. If two backends attempt to
* add children to the same parent simultaneously, and that parent has
* no pre-existing children, then both will attempt to update the
* parent's relhassubclass field, leading to a "tuple concurrently
* updated" error. Also, this interlocks against a concurrent ANALYZE
* on the parent table, which might otherwise be attempting to clear
* the parent's relhassubclass field, if its previous children were
* recently dropped.
*/
relation = heap_openrv(parent, ShareUpdateExclusiveLock);
if (relation->rd_rel->relkind != RELKIND_RELATION)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("inherited relation \"%s\" is not a table",
parent->relname)));
/* Permanent rels cannot inherit from temporary ones */
if (relpersistence != RELPERSISTENCE_TEMP &&
relation->rd_rel->relpersistence == RELPERSISTENCE_TEMP)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
2005-10-15 04:49:52 +02:00
errmsg("cannot inherit from temporary relation \"%s\"",
parent->relname)));
/* If existing rel is temp, it must belong to this session */
if (relation->rd_rel->relpersistence == RELPERSISTENCE_TEMP &&
!relation->rd_islocaltemp)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("cannot inherit from temporary relation of another session")));
/*
* We should have an UNDER permission flag for this, but for now,
* demand that creator of a child table own the parent.
*/
if (!pg_class_ownercheck(RelationGetRelid(relation), GetUserId()))
aclcheck_error(ACLCHECK_NOT_OWNER, ACL_KIND_CLASS,
RelationGetRelationName(relation));
/*
* Reject duplications in the list of parents.
*/
if (list_member_oid(parentOids, RelationGetRelid(relation)))
ereport(ERROR,
(errcode(ERRCODE_DUPLICATE_TABLE),
2007-11-15 22:14:46 +01:00
errmsg("relation \"%s\" would be inherited from more than once",
parent->relname)));
parentOids = lappend_oid(parentOids, RelationGetRelid(relation));
if (relation->rd_rel->relhasoids)
parentsWithOids++;
tupleDesc = RelationGetDescr(relation);
constr = tupleDesc->constr;
/*
2005-10-15 04:49:52 +02:00
* newattno[] will contain the child-table attribute numbers for the
* attributes of this parent table. (They are not the same for
* parents after the first one, nor if we have dropped columns.)
*/
newattno = (AttrNumber *)
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
palloc0(tupleDesc->natts * sizeof(AttrNumber));
for (parent_attno = 1; parent_attno <= tupleDesc->natts;
parent_attno++)
{
Form_pg_attribute attribute = tupleDesc->attrs[parent_attno - 1];
char *attributeName = NameStr(attribute->attname);
int exist_attno;
ColumnDef *def;
/*
* Ignore dropped columns in the parent.
*/
if (attribute->attisdropped)
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
continue; /* leave newattno entry as zero */
/*
* Does it conflict with some previously inherited column?
*/
exist_attno = findAttrByName(attributeName, inhSchema);
if (exist_attno > 0)
{
2007-11-15 22:14:46 +01:00
Oid defTypeId;
int32 deftypmod;
Oid defCollId;
/*
* Yes, try to merge the two column definitions. They must
* have the same type, typmod, and collation.
*/
ereport(NOTICE,
(errmsg("merging multiple inherited definitions of column \"%s\"",
attributeName)));
def = (ColumnDef *) list_nth(inhSchema, exist_attno - 1);
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
typenameTypeIdAndMod(NULL, def->typeName, &defTypeId, &deftypmod);
if (defTypeId != attribute->atttypid ||
deftypmod != attribute->atttypmod)
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
2005-10-15 04:49:52 +02:00
errmsg("inherited column \"%s\" has a type conflict",
attributeName),
errdetail("%s versus %s",
TypeNameToString(def->typeName),
2005-10-15 04:49:52 +02:00
format_type_be(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
defCollId = GetColumnDefCollation(NULL, def, defTypeId);
if (defCollId != attribute->attcollation)
ereport(ERROR,
(errcode(ERRCODE_COLLATION_MISMATCH),
2011-04-10 17:42:00 +02:00
errmsg("inherited column \"%s\" has a collation conflict",
attributeName),
errdetail("\"%s\" versus \"%s\"",
get_collation_name(defCollId),
2011-04-10 17:42:00 +02:00
get_collation_name(attribute->attcollation))));
/* Copy storage parameter */
if (def->storage == 0)
def->storage = attribute->attstorage;
else if (def->storage != attribute->attstorage)
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
2010-02-26 03:01:40 +01:00
errmsg("inherited column \"%s\" has a storage parameter conflict",
attributeName),
errdetail("%s versus %s",
storage_name(def->storage),
storage_name(attribute->attstorage))));
def->inhcount++;
/* Merge of NOT NULL constraints = OR 'em together */
def->is_not_null |= attribute->attnotnull;
/* Default and other constraints are handled below */
newattno[parent_attno - 1] = exist_attno;
}
else
{
/*
* No, create a new inherited column
*/
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 = 1;
def->is_local = false;
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 = attribute->attstorage;
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;
inhSchema = lappend(inhSchema, def);
newattno[parent_attno - 1] = ++child_attno;
}
/*
* Copy default if any
*/
if (attribute->atthasdef)
{
Node *this_default = NULL;
AttrDefault *attrdef;
int i;
/* Find default in constraint structure */
Assert(constr != NULL);
attrdef = constr->defval;
for (i = 0; i < constr->num_defval; i++)
{
if (attrdef[i].adnum == parent_attno)
{
this_default = stringToNode(attrdef[i].adbin);
break;
}
}
Assert(this_default != NULL);
/*
2005-10-15 04:49:52 +02:00
* If default expr could contain any vars, we'd need to fix
* 'em, but it can't; so default is ready to apply to child.
*
* If we already had a default from some prior parent, check
* to see if they are the same. If so, no problem; if not,
* mark the column as having a bogus default. Below, we will
2005-10-15 04:49:52 +02:00
* complain if the bogus default isn't overridden by the child
* schema.
*/
Assert(def->raw_default == NULL);
if (def->cooked_default == NULL)
def->cooked_default = this_default;
else if (!equal(def->cooked_default, this_default))
{
def->cooked_default = &bogus_marker;
have_bogus_defaults = true;
}
}
}
/*
* Now copy the CHECK constraints of this parent, adjusting attnos
* using the completed newattno[] map. Identically named constraints
* are merged if possible, else we throw error.
*/
if (constr && constr->num_check > 0)
{
ConstrCheck *check = constr->check;
int i;
for (i = 0; i < constr->num_check; i++)
{
char *name = check[i].ccname;
Node *expr;
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;
/* ignore if the constraint is non-inheritable */
if (check[i].ccnoinherit)
continue;
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 */
expr = map_variable_attnos(stringToNode(check[i].ccbin),
1, 0,
newattno, tupleDesc->natts,
&found_whole_row);
/*
* For the moment we have to reject whole-row variables. We
* could convert them, if we knew the new table's rowtype OID,
* but that hasn't been assigned yet.
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"),
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
errdetail("Constraint \"%s\" contains a whole-row reference to table \"%s\".",
name,
RelationGetRelationName(relation))));
/* check for duplicate */
if (!MergeCheckConstraint(constraints, name, expr))
{
/* nope, this is a new one */
CookedConstraint *cooked;
cooked = (CookedConstraint *) palloc(sizeof(CookedConstraint));
cooked->contype = CONSTR_CHECK;
cooked->name = pstrdup(name);
cooked->attnum = 0; /* not used for constraints */
cooked->expr = expr;
cooked->skip_validation = false;
cooked->is_local = false;
cooked->inhcount = 1;
cooked->is_no_inherit = false;
constraints = lappend(constraints, cooked);
}
}
}
pfree(newattno);
/*
2005-10-15 04:49:52 +02:00
* 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.
*/
heap_close(relation, NoLock);
}
/*
* If we had no inherited attributes, the result schema is just the
2005-10-15 04:49:52 +02:00
* explicitly declared columns. Otherwise, we need to merge the declared
* columns into the inherited schema list.
*/
if (inhSchema != NIL)
{
foreach(entry, schema)
{
ColumnDef *newdef = lfirst(entry);
char *attributeName = newdef->colname;
int exist_attno;
/*
* Does it conflict with some previously inherited column?
*/
exist_attno = findAttrByName(attributeName, inhSchema);
if (exist_attno > 0)
{
ColumnDef *def;
2007-11-15 22:14:46 +01:00
Oid defTypeId,
newTypeId;
int32 deftypmod,
newtypmod;
Oid defcollid,
newcollid;
/*
* Yes, try to merge the two column definitions. They must
* have the same type, typmod, and collation.
*/
ereport(NOTICE,
2005-10-15 04:49:52 +02:00
(errmsg("merging column \"%s\" with inherited definition",
attributeName)));
def = (ColumnDef *) list_nth(inhSchema, exist_attno - 1);
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
typenameTypeIdAndMod(NULL, def->typeName, &defTypeId, &deftypmod);
typenameTypeIdAndMod(NULL, newdef->typeName, &newTypeId, &newtypmod);
if (defTypeId != newTypeId || deftypmod != newtypmod)
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
2004-08-29 07:07:03 +02:00
errmsg("column \"%s\" has a type conflict",
attributeName),
errdetail("%s versus %s",
TypeNameToString(def->typeName),
TypeNameToString(newdef->typeName))));
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
defcollid = GetColumnDefCollation(NULL, def, defTypeId);
newcollid = GetColumnDefCollation(NULL, newdef, newTypeId);
if (defcollid != newcollid)
ereport(ERROR,
(errcode(ERRCODE_COLLATION_MISMATCH),
errmsg("column \"%s\" has a collation conflict",
attributeName),
errdetail("\"%s\" versus \"%s\"",
get_collation_name(defcollid),
get_collation_name(newcollid))));
/* Copy storage parameter */
if (def->storage == 0)
def->storage = newdef->storage;
else if (newdef->storage != 0 && def->storage != newdef->storage)
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
2010-02-26 03:01:40 +01:00
errmsg("column \"%s\" has a storage parameter conflict",
attributeName),
errdetail("%s versus %s",
storage_name(def->storage),
storage_name(newdef->storage))));
/* Mark the column as locally defined */
def->is_local = true;
/* Merge of NOT NULL constraints = OR 'em together */
def->is_not_null |= newdef->is_not_null;
/* If new def has a default, override previous default */
if (newdef->raw_default != NULL)
{
def->raw_default = newdef->raw_default;
def->cooked_default = newdef->cooked_default;
}
}
else
{
/*
* No, attach new column to result schema
*/
inhSchema = lappend(inhSchema, newdef);
}
}
schema = inhSchema;
/*
2005-10-15 04:49:52 +02:00
* Check that we haven't exceeded the legal # of columns after merging
* in inherited columns.
*/
if (list_length(schema) > MaxHeapAttributeNumber)
ereport(ERROR,
(errcode(ERRCODE_TOO_MANY_COLUMNS),
errmsg("tables can have at most %d columns",
MaxHeapAttributeNumber)));
}
/*
2005-10-15 04:49:52 +02:00
* If we found any conflicting parent default values, check to make sure
* they were overridden by the child.
*/
if (have_bogus_defaults)
{
foreach(entry, schema)
{
ColumnDef *def = lfirst(entry);
if (def->cooked_default == &bogus_marker)
ereport(ERROR,
(errcode(ERRCODE_INVALID_COLUMN_DEFINITION),
2005-10-15 04:49:52 +02:00
errmsg("column \"%s\" inherits conflicting default values",
def->colname),
errhint("To resolve the conflict, specify a default explicitly.")));
}
}
*supOids = parentOids;
*supconstr = constraints;
*supOidCount = parentsWithOids;
return schema;
}
/*
* MergeCheckConstraint
* Try to merge an inherited CHECK constraint with previous ones
*
* If we inherit identically-named constraints from multiple parents, we must
* merge them, or throw an error if they don't have identical definitions.
*
* constraints is a list of CookedConstraint structs for previous constraints.
*
* Returns TRUE if merged (constraint is a duplicate), or FALSE if it's
* got a so-far-unique name, or throws error if conflict.
*/
static bool
MergeCheckConstraint(List *constraints, char *name, Node *expr)
{
ListCell *lc;
2006-10-04 02:30:14 +02:00
foreach(lc, constraints)
2006-10-04 02:30:14 +02:00
{
CookedConstraint *ccon = (CookedConstraint *) lfirst(lc);
Assert(ccon->contype == CONSTR_CHECK);
/* Non-matching names never conflict */
if (strcmp(ccon->name, name) != 0)
continue;
if (equal(expr, ccon->expr))
{
/* OK to merge */
ccon->inhcount++;
return true;
}
ereport(ERROR,
(errcode(ERRCODE_DUPLICATE_OBJECT),
errmsg("check constraint name \"%s\" appears multiple times but with different expressions",
name)));
}
return false;
}
/*
* StoreCatalogInheritance
* Updates the system catalogs with proper inheritance information.
*
* supers is a list of the OIDs of the new relation's direct ancestors.
*/
static void
StoreCatalogInheritance(Oid relationId, List *supers)
{
Relation relation;
int16 seqNumber;
ListCell *entry;
/*
* sanity checks
*/
AssertArg(OidIsValid(relationId));
if (supers == NIL)
return;
/*
2005-10-15 04:49:52 +02:00
* Store INHERITS information in pg_inherits using direct ancestors only.
* Also enter dependencies on the direct ancestors, and make sure they are
* marked with relhassubclass = true.
*
* (Once upon a time, both direct and indirect ancestors were found here
* and then entered into pg_ipl. Since that catalog doesn't exist
* anymore, there's no need to look for indirect ancestors.)
*/
relation = heap_open(InheritsRelationId, RowExclusiveLock);
seqNumber = 1;
foreach(entry, supers)
{
Oid parentOid = lfirst_oid(entry);
StoreCatalogInheritance1(relationId, parentOid, seqNumber, relation);
seqNumber++;
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
}
heap_close(relation, RowExclusiveLock);
}
/*
* Make catalog entries showing relationId as being an inheritance child
* of parentOid. inhRelation is the already-opened pg_inherits catalog.
*/
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
static void
StoreCatalogInheritance1(Oid relationId, Oid parentOid,
int16 seqNumber, Relation inhRelation)
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
{
TupleDesc desc = RelationGetDescr(inhRelation);
Datum values[Natts_pg_inherits];
bool nulls[Natts_pg_inherits];
2006-10-04 02:30:14 +02:00
ObjectAddress childobject,
parentobject;
HeapTuple tuple;
/*
* Make the pg_inherits entry
*/
values[Anum_pg_inherits_inhrelid - 1] = ObjectIdGetDatum(relationId);
values[Anum_pg_inherits_inhparent - 1] = ObjectIdGetDatum(parentOid);
values[Anum_pg_inherits_inhseqno - 1] = Int16GetDatum(seqNumber);
memset(nulls, 0, sizeof(nulls));
tuple = heap_form_tuple(desc, values, nulls);
simple_heap_insert(inhRelation, tuple);
CatalogUpdateIndexes(inhRelation, tuple);
heap_freetuple(tuple);
/*
* Store a dependency too
*/
parentobject.classId = RelationRelationId;
parentobject.objectId = parentOid;
parentobject.objectSubId = 0;
childobject.classId = RelationRelationId;
childobject.objectId = relationId;
childobject.objectSubId = 0;
recordDependencyOn(&childobject, &parentobject, DEPENDENCY_NORMAL);
/*
* Post creation hook of this inheritance. Since object_access_hook
* doesn't take multiple object identifiers, we relay oid of parent
* relation using auxiliary_id argument.
*/
InvokeObjectPostAlterHookArg(InheritsRelationId,
relationId, 0,
parentOid, false);
/*
* Mark the parent as having subclasses.
*/
SetRelationHasSubclass(parentOid, true);
}
/*
* Look for an existing schema entry with the given name.
*
* Returns the index (starting with 1) if attribute already exists in schema,
* 0 if it doesn't.
*/
static int
findAttrByName(const char *attributeName, List *schema)
{
ListCell *s;
int i = 1;
foreach(s, schema)
{
ColumnDef *def = lfirst(s);
if (strcmp(attributeName, def->colname) == 0)
return i;
i++;
}
return 0;
}
/*
* SetRelationHasSubclass
* Set the value of the relation's relhassubclass field in pg_class.
*
* NOTE: caller must be holding an appropriate lock on the relation.
* ShareUpdateExclusiveLock is sufficient.
*
* NOTE: an important side-effect of this operation is that an SI invalidation
* message is sent out to all backends --- including me --- causing plans
* referencing the relation to be rebuilt with the new list of children.
* This must happen even if we find that no change is needed in the pg_class
* row.
*/
void
SetRelationHasSubclass(Oid relationId, bool relhassubclass)
{
Relation relationRelation;
HeapTuple tuple;
Form_pg_class classtuple;
/*
* Fetch a modifiable copy of the tuple, modify it, update pg_class.
*/
relationRelation = heap_open(RelationRelationId, RowExclusiveLock);
tuple = SearchSysCacheCopy1(RELOID, ObjectIdGetDatum(relationId));
if (!HeapTupleIsValid(tuple))
elog(ERROR, "cache lookup failed for relation %u", relationId);
classtuple = (Form_pg_class) GETSTRUCT(tuple);
if (classtuple->relhassubclass != relhassubclass)
{
classtuple->relhassubclass = relhassubclass;
simple_heap_update(relationRelation, &tuple->t_self, tuple);
/* keep the catalog indexes up to date */
CatalogUpdateIndexes(relationRelation, tuple);
}
else
{
/* no need to change tuple, but force relcache rebuild anyway */
CacheInvalidateRelcacheByTuple(tuple);
}
heap_freetuple(tuple);
heap_close(relationRelation, RowExclusiveLock);
}
/*
* renameatt_check - basic sanity checks before attribute rename
*/
static void
renameatt_check(Oid myrelid, Form_pg_class classform, bool recursing)
{
char relkind = classform->relkind;
if (classform->reloftype && !recursing)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("cannot rename column of typed table")));
/*
* Renaming the columns of sequences or toast tables doesn't actually
* break anything from the system's point of view, since internal
2010-07-06 21:19:02 +02:00
* references are by attnum. But it doesn't seem right to allow users to
* change names that are hardcoded into the system, hence the following
* restriction.
*/
if (relkind != RELKIND_RELATION &&
relkind != RELKIND_VIEW &&
relkind != RELKIND_MATVIEW &&
relkind != RELKIND_COMPOSITE_TYPE &&
relkind != RELKIND_INDEX &&
relkind != RELKIND_FOREIGN_TABLE)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("\"%s\" is not a table, view, materialized view, composite type, index, or foreign table",
NameStr(classform->relname))));
/*
* permissions checking. only the owner of a class can change its schema.
*/
if (!pg_class_ownercheck(myrelid, GetUserId()))
aclcheck_error(ACLCHECK_NOT_OWNER, ACL_KIND_CLASS,
NameStr(classform->relname));
if (!allowSystemTableMods && IsSystemClass(classform))
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
errmsg("permission denied: \"%s\" is a system catalog",
NameStr(classform->relname))));
}
/*
* renameatt_internal - workhorse for renameatt
*/
static void
renameatt_internal(Oid myrelid,
const char *oldattname,
const char *newattname,
bool recurse,
bool recursing,
int expected_parents,
DropBehavior behavior)
{
Relation targetrelation;
Relation attrelation;
HeapTuple atttup;
Form_pg_attribute attform;
int attnum;
/*
* Grab an exclusive lock on the target table, which we will NOT release
* until end of transaction.
*/
targetrelation = relation_open(myrelid, AccessExclusiveLock);
renameatt_check(myrelid, RelationGetForm(targetrelation), recursing);
/*
* if the 'recurse' flag is set then we are supposed to rename this
* attribute in all classes that inherit from 'relname' (as well as in
* 'relname').
*
* any permissions or problems with duplicate attributes will cause the
* whole transaction to abort, which is what we want -- all or nothing.
*/
if (recurse)
{
2010-02-26 03:01:40 +01:00
List *child_oids,
*child_numparents;
ListCell *lo,
*li;
/*
* we need the number of parents for each child so that the recursive
* calls to renameatt() can determine whether there are any parents
* outside the inheritance hierarchy being processed.
*/
child_oids = find_all_inheritors(myrelid, AccessExclusiveLock,
&child_numparents);
/*
2005-10-15 04:49:52 +02:00
* find_all_inheritors does the recursive search of the inheritance
* hierarchy, so all we have to do is process all of the relids in the
* list that it returns.
*/
forboth(lo, child_oids, li, child_numparents)
{
Oid childrelid = lfirst_oid(lo);
int numparents = lfirst_int(li);
if (childrelid == myrelid)
continue;
/* note we need not recurse again */
renameatt_internal(childrelid, oldattname, newattname, false, true, numparents, behavior);
}
}
else
{
/*
2005-10-15 04:49:52 +02:00
* If we are told not to recurse, there had better not be any child
* tables; else the rename would put them out of step.
*
* expected_parents will only be 0 if we are not already recursing.
*/
if (expected_parents == 0 &&
find_inheritance_children(myrelid, NoLock) != NIL)
ereport(ERROR,
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
errmsg("inherited column \"%s\" must be renamed in child tables too",
oldattname)));
}
/* rename attributes in typed tables of composite type */
if (targetrelation->rd_rel->relkind == RELKIND_COMPOSITE_TYPE)
{
List *child_oids;
ListCell *lo;
child_oids = find_typed_table_dependencies(targetrelation->rd_rel->reltype,
2011-04-10 17:42:00 +02:00
RelationGetRelationName(targetrelation),
behavior);
foreach(lo, child_oids)
renameatt_internal(lfirst_oid(lo), oldattname, newattname, true, true, 0, behavior);
}
attrelation = heap_open(AttributeRelationId, RowExclusiveLock);
2001-03-22 05:01:46 +01:00
atttup = SearchSysCacheCopyAttName(myrelid, oldattname);
if (!HeapTupleIsValid(atttup))
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_COLUMN),
errmsg("column \"%s\" does not exist",
oldattname)));
attform = (Form_pg_attribute) GETSTRUCT(atttup);
attnum = attform->attnum;
if (attnum <= 0)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot rename system column \"%s\"",
oldattname)));
/*
2010-02-26 03:01:40 +01:00
* if the attribute is inherited, forbid the renaming. if this is a
* top-level call to renameatt(), then expected_parents will be 0, so the
* effect of this code will be to prohibit the renaming if the attribute
* is inherited at all. if this is a recursive call to renameatt(),
* expected_parents will be the number of parents the current relation has
2010-02-26 03:01:40 +01:00
* within the inheritance hierarchy being processed, so we'll prohibit the
* renaming only if there are additional parents from elsewhere.
*/
if (attform->attinhcount > expected_parents)
ereport(ERROR,
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
errmsg("cannot rename inherited column \"%s\"",
oldattname)));
/* new name should not already exist */
check_for_column_name_collision(targetrelation, newattname);
/* apply the update */
namestrcpy(&(attform->attname), newattname);
simple_heap_update(attrelation, &atttup->t_self, atttup);
/* keep system catalog indexes current */
CatalogUpdateIndexes(attrelation, atttup);
InvokeObjectPostAlterHook(RelationRelationId, myrelid, attnum);
heap_freetuple(atttup);
heap_close(attrelation, RowExclusiveLock);
relation_close(targetrelation, NoLock); /* close rel but keep lock */
}
/*
* Perform permissions and integrity checks before acquiring a relation lock.
*/
static void
RangeVarCallbackForRenameAttribute(const RangeVar *rv, Oid relid, Oid oldrelid,
void *arg)
{
HeapTuple tuple;
Form_pg_class form;
tuple = SearchSysCache1(RELOID, ObjectIdGetDatum(relid));
if (!HeapTupleIsValid(tuple))
return; /* concurrently dropped */
form = (Form_pg_class) GETSTRUCT(tuple);
renameatt_check(relid, form, false);
ReleaseSysCache(tuple);
}
/*
* renameatt - changes the name of a attribute in a relation
*/
Oid
renameatt(RenameStmt *stmt)
{
Oid relid;
/* lock level taken here should match renameatt_internal */
relid = RangeVarGetRelidExtended(stmt->relation, AccessExclusiveLock,
stmt->missing_ok, false,
RangeVarCallbackForRenameAttribute,
NULL);
if (!OidIsValid(relid))
{
ereport(NOTICE,
(errmsg("relation \"%s\" does not exist, skipping",
stmt->relation->relname)));
return InvalidOid;
}
renameatt_internal(relid,
2011-04-10 17:42:00 +02:00
stmt->subname, /* old att name */
stmt->newname, /* new att name */
interpretInhOption(stmt->relation->inhOpt), /* recursive? */
false, /* recursing? */
0, /* expected inhcount */
stmt->behavior);
/* This is an ALTER TABLE command so it's about the relid */
return relid;
}
/*
* same logic as renameatt_internal
*/
static Oid
rename_constraint_internal(Oid myrelid,
Oid mytypid,
const char *oldconname,
const char *newconname,
bool recurse,
bool recursing,
int expected_parents)
{
Relation targetrelation = NULL;
Oid constraintOid;
HeapTuple tuple;
Form_pg_constraint con;
AssertArg(!myrelid || !mytypid);
if (mytypid)
{
constraintOid = get_domain_constraint_oid(mytypid, oldconname, false);
}
else
{
targetrelation = relation_open(myrelid, AccessExclusiveLock);
/*
* don't tell it whether we're recursing; we allow changing typed
* tables here
*/
renameatt_check(myrelid, RelationGetForm(targetrelation), false);
constraintOid = get_relation_constraint_oid(myrelid, oldconname, false);
}
tuple = SearchSysCache1(CONSTROID, ObjectIdGetDatum(constraintOid));
if (!HeapTupleIsValid(tuple))
elog(ERROR, "cache lookup failed for constraint %u",
constraintOid);
con = (Form_pg_constraint) GETSTRUCT(tuple);
if (myrelid && con->contype == CONSTRAINT_CHECK && !con->connoinherit)
{
if (recurse)
{
List *child_oids,
*child_numparents;
ListCell *lo,
*li;
child_oids = find_all_inheritors(myrelid, AccessExclusiveLock,
&child_numparents);
forboth(lo, child_oids, li, child_numparents)
{
Oid childrelid = lfirst_oid(lo);
int numparents = lfirst_int(li);
if (childrelid == myrelid)
continue;
rename_constraint_internal(childrelid, InvalidOid, oldconname, newconname, false, true, numparents);
}
}
else
{
if (expected_parents == 0 &&
find_inheritance_children(myrelid, NoLock) != NIL)
ereport(ERROR,
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
errmsg("inherited constraint \"%s\" must be renamed in child tables too",
oldconname)));
}
if (con->coninhcount > expected_parents)
ereport(ERROR,
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
errmsg("cannot rename inherited constraint \"%s\"",
oldconname)));
}
if (con->conindid
&& (con->contype == CONSTRAINT_PRIMARY
|| con->contype == CONSTRAINT_UNIQUE
|| con->contype == CONSTRAINT_EXCLUSION))
/* rename the index; this renames the constraint as well */
RenameRelationInternal(con->conindid, newconname, false);
else
RenameConstraintById(constraintOid, newconname);
ReleaseSysCache(tuple);
if (targetrelation)
relation_close(targetrelation, NoLock); /* close rel but keep lock */
return constraintOid;
}
Oid
RenameConstraint(RenameStmt *stmt)
{
Oid relid = InvalidOid;
Oid typid = InvalidOid;
if (stmt->relationType == OBJECT_DOMAIN)
{
Relation rel;
HeapTuple tup;
typid = typenameTypeId(NULL, makeTypeNameFromNameList(stmt->object));
rel = heap_open(TypeRelationId, RowExclusiveLock);
tup = SearchSysCache1(TYPEOID, ObjectIdGetDatum(typid));
if (!HeapTupleIsValid(tup))
elog(ERROR, "cache lookup failed for type %u", typid);
checkDomainOwner(tup);
ReleaseSysCache(tup);
heap_close(rel, NoLock);
}
else
{
/* lock level taken here should match rename_constraint_internal */
relid = RangeVarGetRelidExtended(stmt->relation, AccessExclusiveLock,
false, false,
RangeVarCallbackForRenameAttribute,
NULL);
}
return
rename_constraint_internal(relid, typid,
stmt->subname,
stmt->newname,
stmt->relation ? interpretInhOption(stmt->relation->inhOpt) : false, /* recursive? */
false, /* recursing? */
0 /* expected inhcount */ );
}
/*
* Execute ALTER TABLE/INDEX/SEQUENCE/VIEW/FOREIGN TABLE RENAME
*/
Oid
RenameRelation(RenameStmt *stmt)
{
Oid relid;
/*
* Grab an exclusive lock on the target table, index, sequence or view,
* which we will NOT release until end of transaction.
*
* Lock level used here should match RenameRelationInternal, to avoid lock
* escalation.
*/
relid = RangeVarGetRelidExtended(stmt->relation, AccessExclusiveLock,
stmt->missing_ok, false,
RangeVarCallbackForAlterRelation,
(void *) stmt);
if (!OidIsValid(relid))
{
ereport(NOTICE,
(errmsg("relation \"%s\" does not exist, skipping",
stmt->relation->relname)));
return InvalidOid;
}
/* Do the work */
RenameRelationInternal(relid, stmt->newname, false);
return relid;
}
/*
* RenameRelationInternal - change the name of a relation
*
* XXX - When renaming sequences, we don't bother to modify the
* sequence name that is stored within the sequence itself
* (this would cause problems with MVCC). In the future,
* the sequence name should probably be removed from the
* sequence, AFAIK there's no need for it to be there.
*/
void
RenameRelationInternal(Oid myrelid, const char *newrelname, bool is_internal)
{
Relation targetrelation;
Relation relrelation; /* for RELATION relation */
HeapTuple reltup;
Form_pg_class relform;
Oid namespaceId;
/*
* Grab an exclusive lock on the target table, index, sequence or view,
* which we will NOT release until end of transaction.
*/
targetrelation = relation_open(myrelid, AccessExclusiveLock);
namespaceId = RelationGetNamespace(targetrelation);
/*
2005-10-15 04:49:52 +02:00
* Find relation's pg_class tuple, and make sure newrelname isn't in use.
*/
relrelation = heap_open(RelationRelationId, RowExclusiveLock);
reltup = SearchSysCacheCopy1(RELOID, ObjectIdGetDatum(myrelid));
2003-08-04 02:43:34 +02:00
if (!HeapTupleIsValid(reltup)) /* shouldn't happen */
elog(ERROR, "cache lookup failed for relation %u", myrelid);
relform = (Form_pg_class) GETSTRUCT(reltup);
if (get_relname_relid(newrelname, namespaceId) != InvalidOid)
ereport(ERROR,
(errcode(ERRCODE_DUPLICATE_TABLE),
errmsg("relation \"%s\" already exists",
newrelname)));
/*
2005-10-15 04:49:52 +02:00
* Update pg_class tuple with new relname. (Scribbling on reltup is OK
* because it's a copy...)
*/
namestrcpy(&(relform->relname), newrelname);
simple_heap_update(relrelation, &reltup->t_self, reltup);
/* keep the system catalog indexes current */
CatalogUpdateIndexes(relrelation, reltup);
InvokeObjectPostAlterHookArg(RelationRelationId, myrelid, 0,
InvalidOid, is_internal);
heap_freetuple(reltup);
heap_close(relrelation, RowExclusiveLock);
/*
* Also rename the associated type, if any.
*/
if (OidIsValid(targetrelation->rd_rel->reltype))
RenameTypeInternal(targetrelation->rd_rel->reltype,
newrelname, namespaceId);
/*
* Also rename the associated constraint, if any.
*/
if (targetrelation->rd_rel->relkind == RELKIND_INDEX)
{
Oid constraintId = get_index_constraint(myrelid);
if (OidIsValid(constraintId))
RenameConstraintById(constraintId, newrelname);
}
/*
* Close rel, but keep exclusive lock!
*/
relation_close(targetrelation, NoLock);
}
/*
* Disallow ALTER TABLE (and similar commands) when the current backend has
* any open reference to the target table besides the one just acquired by
* the calling command; this implies there's an open cursor or active plan.
* We need this check because our lock doesn't protect us against stomping
* on our own foot, only other people's feet!
*
* For ALTER TABLE, the only case known to cause serious trouble is ALTER
* COLUMN TYPE, and some changes are obviously pretty benign, so this could
* possibly be relaxed to only error out for certain types of alterations.
* But the use-case for allowing any of these things is not obvious, so we
* won't work hard at it for now.
*
* We also reject these commands if there are any pending AFTER trigger events
* for the rel. This is certainly necessary for the rewriting variants of
* ALTER TABLE, because they don't preserve tuple TIDs and so the pending
* events would try to fetch the wrong tuples. It might be overly cautious
* in other cases, but again it seems better to err on the side of paranoia.
*
* REINDEX calls this with "rel" referencing the index to be rebuilt; here
* we are worried about active indexscans on the index. The trigger-event
* check can be skipped, since we are doing no damage to the parent table.
*
* The statement name (eg, "ALTER TABLE") is passed for use in error messages.
*/
void
CheckTableNotInUse(Relation rel, const char *stmt)
{
int expected_refcnt;
expected_refcnt = rel->rd_isnailed ? 2 : 1;
if (rel->rd_refcnt != expected_refcnt)
ereport(ERROR,
(errcode(ERRCODE_OBJECT_IN_USE),
/* translator: first %s is a SQL command, eg ALTER TABLE */
errmsg("cannot %s \"%s\" because "
"it is being used by active queries in this session",
stmt, RelationGetRelationName(rel))));
if (rel->rd_rel->relkind != RELKIND_INDEX &&
AfterTriggerPendingOnRel(RelationGetRelid(rel)))
ereport(ERROR,
(errcode(ERRCODE_OBJECT_IN_USE),
/* translator: first %s is a SQL command, eg ALTER TABLE */
errmsg("cannot %s \"%s\" because "
"it has pending trigger events",
stmt, RelationGetRelationName(rel))));
}
/*
* AlterTableLookupRelation
* Look up, and lock, the OID for the relation named by an alter table
* statement.
*/
Oid
AlterTableLookupRelation(AlterTableStmt *stmt, LOCKMODE lockmode)
{
return RangeVarGetRelidExtended(stmt->relation, lockmode, stmt->missing_ok, false,
RangeVarCallbackForAlterRelation,
(void *) stmt);
}
/*
* AlterTable
* Execute ALTER TABLE, which can be a list of subcommands
*
* ALTER TABLE is performed in three phases:
* 1. Examine subcommands and perform pre-transformation checking.
* 2. Update system catalogs.
* 3. Scan table(s) to check new constraints, and optionally recopy
* the data into new table(s).
* Phase 3 is not performed unless one or more of the subcommands requires
2004-08-29 07:07:03 +02:00
* it. The intention of this design is to allow multiple independent
* updates of the table schema to be performed with only one pass over the
* data.
*
2004-08-29 07:07:03 +02:00
* ATPrepCmd performs phase 1. A "work queue" entry is created for
* each table to be affected (there may be multiple affected tables if the
* commands traverse a table inheritance hierarchy). Also we do preliminary
* validation of the subcommands, including parse transformation of those
* expressions that need to be evaluated with respect to the old table
* schema.
*
* ATRewriteCatalogs performs phase 2 for each affected table. (Note that
* phases 2 and 3 normally do no explicit recursion, since phase 1 already
* did it --- although some subcommands have to recurse in phase 2 instead.)
* Certain subcommands need to be performed before others to avoid
* unnecessary conflicts; for example, DROP COLUMN should come before
2004-08-29 07:07:03 +02:00
* ADD COLUMN. Therefore phase 1 divides the subcommands into multiple
* lists, one for each logical "pass" of phase 2.
*
* ATRewriteTables performs phase 3 for those tables that need it.
*
* Thanks to the magic of MVCC, an error anywhere along the way rolls back
* the whole operation; we don't have to do anything special to clean up.
*
* The caller must lock the relation, with an appropriate lock level
* for the subcommands requested. Any subcommand that needs to rewrite
* tuples in the table forces the whole command to be executed with
* AccessExclusiveLock (actually, that is currently required always, but
* we hope to relax it at some point). We pass the lock level down
* so that we can apply it recursively to inherited tables. Note that the
* lock level we want as we recurse might well be higher than required for
* that specific subcommand. So we pass down the overall lock requirement,
* rather than reassess it at lower levels.
*/
void
AlterTable(Oid relid, LOCKMODE lockmode, AlterTableStmt *stmt)
{
Relation rel;
/* Caller is required to provide an adequate lock. */
rel = relation_open(relid, NoLock);
CheckTableNotInUse(rel, "ALTER TABLE");
ATController(rel, stmt->cmds, interpretInhOption(stmt->relation->inhOpt),
2011-04-10 17:42:00 +02:00
lockmode);
}
/*
* AlterTableInternal
*
* ALTER TABLE with target specified by OID
*
* We do not reject if the relation is already open, because it's quite
* likely that one or more layers of caller have it open. That means it
* is unsafe to use this entry point for alterations that could break
* existing query plans. On the assumption it's not used for such, we
* don't have to reject pending AFTER triggers, either.
*/
void
AlterTableInternal(Oid relid, List *cmds, bool recurse)
{
Relation rel;
2011-04-10 17:42:00 +02:00
LOCKMODE lockmode = AlterTableGetLockLevel(cmds);
rel = relation_open(relid, lockmode);
ATController(rel, cmds, recurse, lockmode);
}
/*
* AlterTableGetLockLevel
*
* Sets the overall lock level required for the supplied list of subcommands.
* Policy for doing this set according to needs of AlterTable(), see
* comments there for overall explanation.
*
* Function is called before and after parsing, so it must give same
* answer each time it is called. Some subcommands are transformed
* into other subcommand types, so the transform must never be made to a
* lower lock level than previously assigned. All transforms are noted below.
*
* Since this is called before we lock the table we cannot use table metadata
* to influence the type of lock we acquire.
*
* There should be no lockmodes hardcoded into the subcommand functions. All
* lockmode decisions for ALTER TABLE are made here only. The one exception is
* ALTER TABLE RENAME which is treated as a different statement type T_RenameStmt
* and does not travel through this section of code and cannot be combined with
* any of the subcommands given here.
*/
LOCKMODE
AlterTableGetLockLevel(List *cmds)
{
/*
* Late in 9.1 dev cycle a number of issues were uncovered with access to
* catalog relations, leading to the decision to re-enforce all DDL at
* AccessExclusiveLock level by default.
*
* The issues are that there is a pervasive assumption in the code that
* the catalogs will not be read unless an AccessExclusiveLock is held. If
* that rule is relaxed, we must protect against a number of potential
* effects - infrequent, but proven possible with test cases where
* multiple DDL operations occur in a stream against frequently accessed
* tables.
*
* 1. Catalog tables are read using SnapshotNow, which has a race bug that
* allows a scan to return no valid rows even when one is present in the
* case of a commit of a concurrent update of the catalog table.
* SnapshotNow also ignores transactions in progress, so takes the latest
* committed version without waiting for the latest changes.
*
* 2. Relcache needs to be internally consistent, so unless we lock the
* definition during reads we have no way to guarantee that.
*
* 3. Catcache access isn't coordinated at all so refreshes can occur at
* any time.
*/
#ifdef REDUCED_ALTER_TABLE_LOCK_LEVELS
ListCell *lcmd;
2011-04-10 17:42:00 +02:00
LOCKMODE lockmode = ShareUpdateExclusiveLock;
foreach(lcmd, cmds)
{
AlterTableCmd *cmd = (AlterTableCmd *) lfirst(lcmd);
2011-04-10 17:42:00 +02:00
LOCKMODE cmd_lockmode = AccessExclusiveLock; /* default for compiler */
switch (cmd->subtype)
{
2011-04-10 17:42:00 +02:00
/*
* Need AccessExclusiveLock for these subcommands because they
* affect or potentially affect both read and write
* operations.
*
* New subcommand types should be added here by default.
*/
case AT_AddColumn: /* may rewrite heap, in some cases and visible
* to SELECT */
case AT_DropColumn: /* change visible to SELECT */
case AT_AddColumnToView: /* CREATE VIEW */
case AT_AlterColumnType: /* must rewrite heap */
case AT_DropConstraint: /* as DROP INDEX */
2011-04-10 17:42:00 +02:00
case AT_AddOids: /* must rewrite heap */
case AT_DropOids: /* calls AT_DropColumn */
case AT_EnableAlwaysRule: /* may change SELECT rules */
case AT_EnableReplicaRule: /* may change SELECT rules */
2011-04-10 17:42:00 +02:00
case AT_EnableRule: /* may change SELECT rules */
case AT_DisableRule: /* may change SELECT rules */
case AT_ChangeOwner: /* change visible to SELECT */
case AT_SetTableSpace: /* must rewrite heap */
case AT_DropNotNull: /* may change some SQL plans */
case AT_SetNotNull:
case AT_GenericOptions:
case AT_AlterColumnGenericOptions:
cmd_lockmode = AccessExclusiveLock;
break;
2011-04-10 17:42:00 +02:00
/*
* These subcommands affect write operations only.
*/
case AT_ColumnDefault:
2011-04-10 17:42:00 +02:00
case AT_ProcessedConstraint: /* becomes AT_AddConstraint */
case AT_AddConstraintRecurse: /* becomes AT_AddConstraint */
case AT_ReAddConstraint: /* becomes AT_AddConstraint */
case AT_EnableTrig:
case AT_EnableAlwaysTrig:
case AT_EnableReplicaTrig:
case AT_EnableTrigAll:
case AT_EnableTrigUser:
case AT_DisableTrig:
case AT_DisableTrigAll:
case AT_DisableTrigUser:
2011-04-10 17:42:00 +02:00
case AT_AddIndex: /* from ADD CONSTRAINT */
case AT_AddIndexConstraint:
cmd_lockmode = ShareRowExclusiveLock;
break;
case AT_AddConstraint:
if (IsA(cmd->def, Constraint))
{
Constraint *con = (Constraint *) cmd->def;
switch (con->contype)
{
case CONSTR_EXCLUSION:
case CONSTR_PRIMARY:
case CONSTR_UNIQUE:
2011-04-10 17:42:00 +02:00
/*
* Cases essentially the same as CREATE INDEX. We
2011-04-10 17:42:00 +02:00
* could reduce the lock strength to ShareLock if
* we can work out how to allow concurrent catalog
* updates.
*/
cmd_lockmode = ShareRowExclusiveLock;
break;
case CONSTR_FOREIGN:
2011-04-10 17:42:00 +02:00
/*
* We add triggers to both tables when we add a
* Foreign Key, so the lock level must be at least
* as strong as CREATE TRIGGER.
*/
cmd_lockmode = ShareRowExclusiveLock;
break;
default:
cmd_lockmode = ShareRowExclusiveLock;
}
}
break;
2011-04-10 17:42:00 +02:00
/*
* These subcommands affect inheritance behaviour. Queries
* started before us will continue to see the old inheritance
* behaviour, while queries started after we commit will see
* new behaviour. No need to prevent reads or writes to the
* subtable while we hook it up though.
2011-04-10 17:42:00 +02:00
*/
case AT_AddInherit:
case AT_DropInherit:
cmd_lockmode = ShareUpdateExclusiveLock;
break;
/*
* These subcommands affect implicit row type conversion. They
* have affects similar to CREATE/DROP CAST on queries. We
* don't provide for invalidating parse trees as a result of
2011-06-09 20:32:50 +02:00
* such changes. Do avoid concurrent pg_class updates,
* though.
*/
case AT_AddOf:
case AT_DropOf:
cmd_lockmode = ShareUpdateExclusiveLock;
2011-04-10 17:42:00 +02:00
/*
* These subcommands affect general strategies for performance
* and maintenance, though don't change the semantic results
* from normal data reads and writes. Delaying an ALTER TABLE
* behind currently active writes only delays the point where
* the new strategy begins to take effect, so there is no
* benefit in waiting. In this case the minimum restriction
* applies: we don't currently allow concurrent catalog
* updates.
*/
case AT_SetStatistics:
case AT_ClusterOn:
case AT_DropCluster:
case AT_SetRelOptions:
case AT_ResetRelOptions:
case AT_ReplaceRelOptions:
case AT_SetOptions:
case AT_ResetOptions:
case AT_SetStorage:
case AT_ValidateConstraint:
cmd_lockmode = ShareUpdateExclusiveLock;
break;
2011-04-10 17:42:00 +02:00
default: /* oops */
elog(ERROR, "unrecognized alter table type: %d",
(int) cmd->subtype);
break;
}
/*
* Take the greatest lockmode from any subcommand
*/
if (cmd_lockmode > lockmode)
lockmode = cmd_lockmode;
}
#else
LOCKMODE lockmode = AccessExclusiveLock;
#endif
return lockmode;
}
static void
ATController(Relation rel, List *cmds, bool recurse, LOCKMODE lockmode)
{
List *wqueue = NIL;
ListCell *lcmd;
/* Phase 1: preliminary examination of commands, create work queue */
foreach(lcmd, cmds)
{
AlterTableCmd *cmd = (AlterTableCmd *) lfirst(lcmd);
ATPrepCmd(&wqueue, rel, cmd, recurse, false, lockmode);
}
/* Close the relation, but keep lock until commit */
relation_close(rel, NoLock);
/* Phase 2: update system catalogs */
ATRewriteCatalogs(&wqueue, lockmode);
/* Phase 3: scan/rewrite tables as needed */
ATRewriteTables(&wqueue, lockmode);
}
/*
* ATPrepCmd
*
* Traffic cop for ALTER TABLE Phase 1 operations, including simple
* recursion and permission checks.
*
* Caller must have acquired appropriate lock type on relation already.
* This lock should be held until commit.
*/
static void
ATPrepCmd(List **wqueue, Relation rel, AlterTableCmd *cmd,
bool recurse, bool recursing, LOCKMODE lockmode)
{
AlteredTableInfo *tab;
int pass;
/* Find or create work queue entry for this table */
tab = ATGetQueueEntry(wqueue, rel);
/*
* Copy the original subcommand for each table. This avoids conflicts
* when different child tables need to make different parse
2005-10-15 04:49:52 +02:00
* transformations (for example, the same column may have different column
* numbers in different children).
*/
cmd = copyObject(cmd);
/*
2005-10-15 04:49:52 +02:00
* Do permissions checking, recursion to child tables if needed, and any
* additional phase-1 processing needed.
*/
switch (cmd->subtype)
{
case AT_AddColumn: /* ADD COLUMN */
ATSimplePermissions(rel,
2011-04-10 17:42:00 +02:00
ATT_TABLE | ATT_COMPOSITE_TYPE | ATT_FOREIGN_TABLE);
ATPrepAddColumn(wqueue, rel, recurse, recursing, cmd, lockmode);
/* Recursion occurs during execution phase */
pass = AT_PASS_ADD_COL;
break;
case AT_AddColumnToView: /* add column via CREATE OR REPLACE
* VIEW */
ATSimplePermissions(rel, ATT_VIEW);
ATPrepAddColumn(wqueue, rel, recurse, recursing, cmd, lockmode);
/* Recursion occurs during execution phase */
pass = AT_PASS_ADD_COL;
break;
case AT_ColumnDefault: /* ALTER COLUMN DEFAULT */
2004-08-29 07:07:03 +02:00
/*
2005-10-15 04:49:52 +02:00
* We allow defaults on views so that INSERT into a view can have
* default-ish behavior. This works because the rewriter
* substitutes default values into INSERTs before it expands
* rules.
*/
ATSimplePermissions(rel, ATT_TABLE | ATT_VIEW | ATT_FOREIGN_TABLE);
ATSimpleRecursion(wqueue, rel, cmd, recurse, lockmode);
/* No command-specific prep needed */
pass = cmd->def ? AT_PASS_ADD_CONSTR : AT_PASS_DROP;
break;
case AT_DropNotNull: /* ALTER COLUMN DROP NOT NULL */
2011-04-10 17:42:00 +02:00
ATSimplePermissions(rel, ATT_TABLE | ATT_FOREIGN_TABLE);
ATSimpleRecursion(wqueue, rel, cmd, recurse, lockmode);
/* No command-specific prep needed */
pass = AT_PASS_DROP;
break;
case AT_SetNotNull: /* ALTER COLUMN SET NOT NULL */
2011-04-10 17:42:00 +02:00
ATSimplePermissions(rel, ATT_TABLE | ATT_FOREIGN_TABLE);
ATSimpleRecursion(wqueue, rel, cmd, recurse, lockmode);
/* No command-specific prep needed */
pass = AT_PASS_ADD_CONSTR;
break;
case AT_SetStatistics: /* ALTER COLUMN SET STATISTICS */
ATSimpleRecursion(wqueue, rel, cmd, recurse, lockmode);
/* Performs own permission checks */
ATPrepSetStatistics(rel, cmd->name, cmd->def, lockmode);
pass = AT_PASS_MISC;
break;
case AT_SetOptions: /* ALTER COLUMN SET ( options ) */
case AT_ResetOptions: /* ALTER COLUMN RESET ( options ) */
ATSimplePermissions(rel, ATT_TABLE | ATT_MATVIEW | ATT_INDEX | ATT_FOREIGN_TABLE);
/* This command never recurses */
pass = AT_PASS_MISC;
break;
case AT_SetStorage: /* ALTER COLUMN SET STORAGE */
ATSimplePermissions(rel, ATT_TABLE | ATT_MATVIEW);
ATSimpleRecursion(wqueue, rel, cmd, recurse, lockmode);
/* No command-specific prep needed */
pass = AT_PASS_MISC;
break;
case AT_DropColumn: /* DROP COLUMN */
ATSimplePermissions(rel,
2011-04-10 17:42:00 +02:00
ATT_TABLE | ATT_COMPOSITE_TYPE | ATT_FOREIGN_TABLE);
ATPrepDropColumn(wqueue, rel, recurse, recursing, cmd, lockmode);
/* Recursion occurs during execution phase */
pass = AT_PASS_DROP;
break;
case AT_AddIndex: /* ADD INDEX */
ATSimplePermissions(rel, ATT_TABLE | ATT_MATVIEW);
/* This command never recurses */
/* No command-specific prep needed */
pass = AT_PASS_ADD_INDEX;
break;
case AT_AddConstraint: /* ADD CONSTRAINT */
ATSimplePermissions(rel, ATT_TABLE);
/* Recursion occurs during execution phase */
/* No command-specific prep needed except saving recurse flag */
if (recurse)
cmd->subtype = AT_AddConstraintRecurse;
pass = AT_PASS_ADD_CONSTR;
break;
2011-04-10 17:42:00 +02:00
case AT_AddIndexConstraint: /* ADD CONSTRAINT USING INDEX */
ATSimplePermissions(rel, ATT_TABLE);
/* This command never recurses */
/* No command-specific prep needed */
pass = AT_PASS_ADD_CONSTR;
break;
case AT_DropConstraint: /* DROP CONSTRAINT */
ATSimplePermissions(rel, ATT_TABLE);
/* Recursion occurs during execution phase */
/* No command-specific prep needed except saving recurse flag */
if (recurse)
cmd->subtype = AT_DropConstraintRecurse;
pass = AT_PASS_DROP;
break;
2004-08-29 07:07:03 +02:00
case AT_AlterColumnType: /* ALTER COLUMN TYPE */
ATSimplePermissions(rel,
2011-04-10 17:42:00 +02:00
ATT_TABLE | ATT_COMPOSITE_TYPE | ATT_FOREIGN_TABLE);
/* Performs own recursion */
ATPrepAlterColumnType(wqueue, tab, rel, recurse, recursing, cmd, lockmode);
pass = AT_PASS_ALTER_TYPE;
break;
case AT_AlterColumnGenericOptions:
ATSimplePermissions(rel, ATT_FOREIGN_TABLE);
/* This command never recurses */
/* No command-specific prep needed */
pass = AT_PASS_MISC;
break;
case AT_ChangeOwner: /* ALTER OWNER */
/* This command never recurses */
/* No command-specific prep needed */
pass = AT_PASS_MISC;
break;
2004-08-29 07:07:03 +02:00
case AT_ClusterOn: /* CLUSTER ON */
case AT_DropCluster: /* SET WITHOUT CLUSTER */
ATSimplePermissions(rel, ATT_TABLE | ATT_MATVIEW);
/* These commands never recurse */
/* No command-specific prep needed */
pass = AT_PASS_MISC;
break;
case AT_AddOids: /* SET WITH OIDS */
ATSimplePermissions(rel, ATT_TABLE);
if (!rel->rd_rel->relhasoids || recursing)
ATPrepAddOids(wqueue, rel, recurse, cmd, lockmode);
/* Recursion occurs during execution phase */
pass = AT_PASS_ADD_COL;
break;
2004-08-29 07:07:03 +02:00
case AT_DropOids: /* SET WITHOUT OIDS */
ATSimplePermissions(rel, ATT_TABLE);
/* Performs own recursion */
if (rel->rd_rel->relhasoids)
{
AlterTableCmd *dropCmd = makeNode(AlterTableCmd);
dropCmd->subtype = AT_DropColumn;
dropCmd->name = pstrdup("oid");
dropCmd->behavior = cmd->behavior;
ATPrepCmd(wqueue, rel, dropCmd, recurse, false, lockmode);
}
pass = AT_PASS_DROP;
break;
case AT_SetTableSpace: /* SET TABLESPACE */
ATSimplePermissions(rel, ATT_TABLE | ATT_MATVIEW | ATT_INDEX);
/* This command never recurses */
ATPrepSetTableSpace(tab, rel, cmd->name, lockmode);
2004-08-29 07:07:03 +02:00
pass = AT_PASS_MISC; /* doesn't actually matter */
break;
2006-10-04 02:30:14 +02:00
case AT_SetRelOptions: /* SET (...) */
case AT_ResetRelOptions: /* RESET (...) */
case AT_ReplaceRelOptions: /* reset them all, then set just these */
ATSimplePermissions(rel, ATT_TABLE | ATT_VIEW | ATT_MATVIEW | ATT_INDEX);
/* This command never recurses */
/* No command-specific prep needed */
pass = AT_PASS_MISC;
break;
case AT_AddInherit: /* INHERIT */
ATSimplePermissions(rel, ATT_TABLE);
/* This command never recurses */
ATPrepAddInherit(rel);
pass = AT_PASS_MISC;
break;
case AT_ValidateConstraint: /* VALIDATE CONSTRAINT */
ATSimplePermissions(rel, ATT_TABLE);
/* Recursion occurs during execution phase */
/* No command-specific prep needed except saving recurse flag */
if (recurse)
cmd->subtype = AT_ValidateConstraintRecurse;
pass = AT_PASS_MISC;
break;
case AT_EnableTrig: /* ENABLE TRIGGER variants */
Changes pg_trigger and extend pg_rewrite in order to allow triggers and rules to be defined with different, per session controllable, behaviors for replication purposes. This will allow replication systems like Slony-I and, as has been stated on pgsql-hackers, other products to control the firing mechanism of triggers and rewrite rules without modifying the system catalog directly. The firing mechanisms are controlled by a new superuser-only GUC variable, session_replication_role, together with a change to pg_trigger.tgenabled and a new column pg_rewrite.ev_enabled. Both columns are a single char data type now (tgenabled was a bool before). The possible values in these attributes are: 'O' - Trigger/Rule fires when session_replication_role is "origin" (default) or "local". This is the default behavior. 'D' - Trigger/Rule is disabled and fires never 'A' - Trigger/Rule fires always regardless of the setting of session_replication_role 'R' - Trigger/Rule fires when session_replication_role is "replica" The GUC variable can only be changed as long as the system does not have any cached query plans. This will prevent changing the session role and accidentally executing stored procedures or functions that have plans cached that expand to the wrong query set due to differences in the rule firing semantics. The SQL syntax for changing a triggers/rules firing semantics is ALTER TABLE <tabname> <when> TRIGGER|RULE <name>; <when> ::= ENABLE | ENABLE ALWAYS | ENABLE REPLICA | DISABLE psql's \d command as well as pg_dump are extended in a backward compatible fashion. Jan
2007-03-20 00:38:32 +01:00
case AT_EnableAlwaysTrig:
case AT_EnableReplicaTrig:
case AT_EnableTrigAll:
case AT_EnableTrigUser:
case AT_DisableTrig: /* DISABLE TRIGGER variants */
case AT_DisableTrigAll:
case AT_DisableTrigUser:
Changes pg_trigger and extend pg_rewrite in order to allow triggers and rules to be defined with different, per session controllable, behaviors for replication purposes. This will allow replication systems like Slony-I and, as has been stated on pgsql-hackers, other products to control the firing mechanism of triggers and rewrite rules without modifying the system catalog directly. The firing mechanisms are controlled by a new superuser-only GUC variable, session_replication_role, together with a change to pg_trigger.tgenabled and a new column pg_rewrite.ev_enabled. Both columns are a single char data type now (tgenabled was a bool before). The possible values in these attributes are: 'O' - Trigger/Rule fires when session_replication_role is "origin" (default) or "local". This is the default behavior. 'D' - Trigger/Rule is disabled and fires never 'A' - Trigger/Rule fires always regardless of the setting of session_replication_role 'R' - Trigger/Rule fires when session_replication_role is "replica" The GUC variable can only be changed as long as the system does not have any cached query plans. This will prevent changing the session role and accidentally executing stored procedures or functions that have plans cached that expand to the wrong query set due to differences in the rule firing semantics. The SQL syntax for changing a triggers/rules firing semantics is ALTER TABLE <tabname> <when> TRIGGER|RULE <name>; <when> ::= ENABLE | ENABLE ALWAYS | ENABLE REPLICA | DISABLE psql's \d command as well as pg_dump are extended in a backward compatible fashion. Jan
2007-03-20 00:38:32 +01:00
case AT_EnableRule: /* ENABLE/DISABLE RULE variants */
case AT_EnableAlwaysRule:
case AT_EnableReplicaRule:
case AT_DisableRule:
case AT_DropInherit: /* NO INHERIT */
case AT_AddOf: /* OF */
2011-06-09 20:32:50 +02:00
case AT_DropOf: /* NOT OF */
ATSimplePermissions(rel, ATT_TABLE);
/* These commands never recurse */
/* No command-specific prep needed */
pass = AT_PASS_MISC;
break;
case AT_GenericOptions:
ATSimplePermissions(rel, ATT_FOREIGN_TABLE);
/* No command-specific prep needed */
pass = AT_PASS_MISC;
break;
2004-08-29 07:07:03 +02:00
default: /* oops */
elog(ERROR, "unrecognized alter table type: %d",
(int) cmd->subtype);
pass = 0; /* keep compiler quiet */
break;
}
/* Add the subcommand to the appropriate list for phase 2 */
tab->subcmds[pass] = lappend(tab->subcmds[pass], cmd);
}
/*
* ATRewriteCatalogs
*
2004-08-29 07:07:03 +02:00
* Traffic cop for ALTER TABLE Phase 2 operations. Subcommands are
* dispatched in a "safe" execution order (designed to avoid unnecessary
* conflicts).
*/
static void
ATRewriteCatalogs(List **wqueue, LOCKMODE lockmode)
{
int pass;
ListCell *ltab;
/*
2005-10-15 04:49:52 +02:00
* We process all the tables "in parallel", one pass at a time. This is
* needed because we may have to propagate work from one table to another
* (specifically, ALTER TYPE on a foreign key's PK has to dispatch the
* re-adding of the foreign key constraint to the other table). Work can
* only be propagated into later passes, however.
*/
for (pass = 0; pass < AT_NUM_PASSES; pass++)
{
/* Go through each table that needs to be processed */
foreach(ltab, *wqueue)
{
AlteredTableInfo *tab = (AlteredTableInfo *) lfirst(ltab);
List *subcmds = tab->subcmds[pass];
Relation rel;
ListCell *lcmd;
if (subcmds == NIL)
continue;
2004-08-29 07:07:03 +02:00
/*
* Appropriate lock was obtained by phase 1, needn't get it again
2004-08-29 07:07:03 +02:00
*/
rel = relation_open(tab->relid, NoLock);
foreach(lcmd, subcmds)
ATExecCmd(wqueue, tab, rel, (AlterTableCmd *) lfirst(lcmd), lockmode);
/*
2005-10-15 04:49:52 +02:00
* After the ALTER TYPE pass, do cleanup work (this is not done in
* ATExecAlterColumnType since it should be done only once if
* multiple columns of a table are altered).
*/
if (pass == AT_PASS_ALTER_TYPE)
ATPostAlterTypeCleanup(wqueue, tab, lockmode);
relation_close(rel, NoLock);
}
}
/* Check to see if a toast table must be added. */
foreach(ltab, *wqueue)
{
AlteredTableInfo *tab = (AlteredTableInfo *) lfirst(ltab);
if (tab->relkind == RELKIND_RELATION ||
tab->relkind == RELKIND_MATVIEW)
AlterTableCreateToastTable(tab->relid, (Datum) 0);
}
}
/*
* ATExecCmd: dispatch a subcommand to appropriate execution routine
*/
static void
ATExecCmd(List **wqueue, AlteredTableInfo *tab, Relation rel,
AlterTableCmd *cmd, LOCKMODE lockmode)
{
switch (cmd->subtype)
{
case AT_AddColumn: /* ADD COLUMN */
case AT_AddColumnToView: /* add column via CREATE OR REPLACE
* VIEW */
ATExecAddColumn(wqueue, tab, rel, (ColumnDef *) cmd->def,
false, false, false, lockmode);
break;
case AT_AddColumnRecurse:
ATExecAddColumn(wqueue, tab, rel, (ColumnDef *) cmd->def,
false, true, false, lockmode);
break;
case AT_ColumnDefault: /* ALTER COLUMN DEFAULT */
ATExecColumnDefault(rel, cmd->name, cmd->def, lockmode);
break;
case AT_DropNotNull: /* ALTER COLUMN DROP NOT NULL */
ATExecDropNotNull(rel, cmd->name, lockmode);
break;
case AT_SetNotNull: /* ALTER COLUMN SET NOT NULL */
ATExecSetNotNull(tab, rel, cmd->name, lockmode);
break;
case AT_SetStatistics: /* ALTER COLUMN SET STATISTICS */
ATExecSetStatistics(rel, cmd->name, cmd->def, lockmode);
break;
case AT_SetOptions: /* ALTER COLUMN SET ( options ) */
ATExecSetOptions(rel, cmd->name, cmd->def, false, lockmode);
break;
case AT_ResetOptions: /* ALTER COLUMN RESET ( options ) */
ATExecSetOptions(rel, cmd->name, cmd->def, true, lockmode);
break;
case AT_SetStorage: /* ALTER COLUMN SET STORAGE */
ATExecSetStorage(rel, cmd->name, cmd->def, lockmode);
break;
case AT_DropColumn: /* DROP COLUMN */
ATExecDropColumn(wqueue, rel, cmd->name,
2011-04-10 17:42:00 +02:00
cmd->behavior, false, false, cmd->missing_ok, lockmode);
break;
2004-08-29 07:07:03 +02:00
case AT_DropColumnRecurse: /* DROP COLUMN with recursion */
ATExecDropColumn(wqueue, rel, cmd->name,
2011-04-10 17:42:00 +02:00
cmd->behavior, true, false, cmd->missing_ok, lockmode);
break;
case AT_AddIndex: /* ADD INDEX */
ATExecAddIndex(tab, rel, (IndexStmt *) cmd->def, false, lockmode);
break;
case AT_ReAddIndex: /* ADD INDEX */
ATExecAddIndex(tab, rel, (IndexStmt *) cmd->def, true, lockmode);
break;
case AT_AddConstraint: /* ADD CONSTRAINT */
ATExecAddConstraint(wqueue, tab, rel, (Constraint *) cmd->def,
false, false, lockmode);
break;
case AT_AddConstraintRecurse: /* ADD CONSTRAINT with recursion */
ATExecAddConstraint(wqueue, tab, rel, (Constraint *) cmd->def,
true, false, lockmode);
break;
case AT_ReAddConstraint: /* Re-add pre-existing check
* constraint */
ATExecAddConstraint(wqueue, tab, rel, (Constraint *) cmd->def,
false, true, lockmode);
break;
2011-04-10 17:42:00 +02:00
case AT_AddIndexConstraint: /* ADD CONSTRAINT USING INDEX */
ATExecAddIndexConstraint(tab, rel, (IndexStmt *) cmd->def, lockmode);
break;
case AT_ValidateConstraint: /* VALIDATE CONSTRAINT */
ATExecValidateConstraint(rel, cmd->name, false, false, lockmode);
break;
case AT_ValidateConstraintRecurse: /* VALIDATE CONSTRAINT with
* recursion */
ATExecValidateConstraint(rel, cmd->name, true, false, lockmode);
break;
case AT_DropConstraint: /* DROP CONSTRAINT */
ATExecDropConstraint(rel, cmd->name, cmd->behavior,
false, false,
cmd->missing_ok, lockmode);
break;
case AT_DropConstraintRecurse: /* DROP CONSTRAINT with recursion */
ATExecDropConstraint(rel, cmd->name, cmd->behavior,
true, false,
cmd->missing_ok, lockmode);
break;
2004-08-29 07:07:03 +02:00
case AT_AlterColumnType: /* ALTER COLUMN TYPE */
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
ATExecAlterColumnType(tab, rel, cmd, lockmode);
break;
case AT_AlterColumnGenericOptions: /* ALTER COLUMN OPTIONS */
ATExecAlterColumnGenericOptions(rel, cmd->name, (List *) cmd->def, lockmode);
break;
case AT_ChangeOwner: /* ALTER OWNER */
ATExecChangeOwner(RelationGetRelid(rel),
get_role_oid(cmd->name, false),
false, lockmode);
break;
case AT_ClusterOn: /* CLUSTER ON */
ATExecClusterOn(rel, cmd->name, lockmode);
break;
2004-08-29 07:07:03 +02:00
case AT_DropCluster: /* SET WITHOUT CLUSTER */
ATExecDropCluster(rel, lockmode);
break;
case AT_AddOids: /* SET WITH OIDS */
/* Use the ADD COLUMN code, unless prep decided to do nothing */
if (cmd->def != NULL)
ATExecAddColumn(wqueue, tab, rel, (ColumnDef *) cmd->def,
true, false, false, lockmode);
break;
case AT_AddOidsRecurse: /* SET WITH OIDS */
/* Use the ADD COLUMN code, unless prep decided to do nothing */
if (cmd->def != NULL)
ATExecAddColumn(wqueue, tab, rel, (ColumnDef *) cmd->def,
true, true, false, lockmode);
break;
case AT_DropOids: /* SET WITHOUT OIDS */
2004-08-29 07:07:03 +02:00
/*
2004-08-29 07:07:03 +02:00
* Nothing to do here; we'll have generated a DropColumn
* subcommand to do the real work
*/
break;
2004-08-29 07:07:03 +02:00
case AT_SetTableSpace: /* SET TABLESPACE */
/*
* Nothing to do here; Phase 3 does the work
*/
break;
2006-10-04 02:30:14 +02:00
case AT_SetRelOptions: /* SET (...) */
case AT_ResetRelOptions: /* RESET (...) */
case AT_ReplaceRelOptions: /* replace entire option list */
ATExecSetRelOptions(rel, (List *) cmd->def, cmd->subtype, lockmode);
break;
2007-11-15 22:14:46 +01:00
case AT_EnableTrig: /* ENABLE TRIGGER name */
ATExecEnableDisableTrigger(rel, cmd->name,
2011-04-10 17:42:00 +02:00
TRIGGER_FIRES_ON_ORIGIN, false, lockmode);
Changes pg_trigger and extend pg_rewrite in order to allow triggers and rules to be defined with different, per session controllable, behaviors for replication purposes. This will allow replication systems like Slony-I and, as has been stated on pgsql-hackers, other products to control the firing mechanism of triggers and rewrite rules without modifying the system catalog directly. The firing mechanisms are controlled by a new superuser-only GUC variable, session_replication_role, together with a change to pg_trigger.tgenabled and a new column pg_rewrite.ev_enabled. Both columns are a single char data type now (tgenabled was a bool before). The possible values in these attributes are: 'O' - Trigger/Rule fires when session_replication_role is "origin" (default) or "local". This is the default behavior. 'D' - Trigger/Rule is disabled and fires never 'A' - Trigger/Rule fires always regardless of the setting of session_replication_role 'R' - Trigger/Rule fires when session_replication_role is "replica" The GUC variable can only be changed as long as the system does not have any cached query plans. This will prevent changing the session role and accidentally executing stored procedures or functions that have plans cached that expand to the wrong query set due to differences in the rule firing semantics. The SQL syntax for changing a triggers/rules firing semantics is ALTER TABLE <tabname> <when> TRIGGER|RULE <name>; <when> ::= ENABLE | ENABLE ALWAYS | ENABLE REPLICA | DISABLE psql's \d command as well as pg_dump are extended in a backward compatible fashion. Jan
2007-03-20 00:38:32 +01:00
break;
2007-11-15 22:14:46 +01:00
case AT_EnableAlwaysTrig: /* ENABLE ALWAYS TRIGGER name */
ATExecEnableDisableTrigger(rel, cmd->name,
TRIGGER_FIRES_ALWAYS, false, lockmode);
Changes pg_trigger and extend pg_rewrite in order to allow triggers and rules to be defined with different, per session controllable, behaviors for replication purposes. This will allow replication systems like Slony-I and, as has been stated on pgsql-hackers, other products to control the firing mechanism of triggers and rewrite rules without modifying the system catalog directly. The firing mechanisms are controlled by a new superuser-only GUC variable, session_replication_role, together with a change to pg_trigger.tgenabled and a new column pg_rewrite.ev_enabled. Both columns are a single char data type now (tgenabled was a bool before). The possible values in these attributes are: 'O' - Trigger/Rule fires when session_replication_role is "origin" (default) or "local". This is the default behavior. 'D' - Trigger/Rule is disabled and fires never 'A' - Trigger/Rule fires always regardless of the setting of session_replication_role 'R' - Trigger/Rule fires when session_replication_role is "replica" The GUC variable can only be changed as long as the system does not have any cached query plans. This will prevent changing the session role and accidentally executing stored procedures or functions that have plans cached that expand to the wrong query set due to differences in the rule firing semantics. The SQL syntax for changing a triggers/rules firing semantics is ALTER TABLE <tabname> <when> TRIGGER|RULE <name>; <when> ::= ENABLE | ENABLE ALWAYS | ENABLE REPLICA | DISABLE psql's \d command as well as pg_dump are extended in a backward compatible fashion. Jan
2007-03-20 00:38:32 +01:00
break;
2007-11-15 22:14:46 +01:00
case AT_EnableReplicaTrig: /* ENABLE REPLICA TRIGGER name */
ATExecEnableDisableTrigger(rel, cmd->name,
2011-04-10 17:42:00 +02:00
TRIGGER_FIRES_ON_REPLICA, false, lockmode);
break;
case AT_DisableTrig: /* DISABLE TRIGGER name */
2007-11-15 22:14:46 +01:00
ATExecEnableDisableTrigger(rel, cmd->name,
TRIGGER_DISABLED, false, lockmode);
break;
case AT_EnableTrigAll: /* ENABLE TRIGGER ALL */
2007-11-15 22:14:46 +01:00
ATExecEnableDisableTrigger(rel, NULL,
2011-04-10 17:42:00 +02:00
TRIGGER_FIRES_ON_ORIGIN, false, lockmode);
break;
case AT_DisableTrigAll: /* DISABLE TRIGGER ALL */
2007-11-15 22:14:46 +01:00
ATExecEnableDisableTrigger(rel, NULL,
TRIGGER_DISABLED, false, lockmode);
break;
case AT_EnableTrigUser: /* ENABLE TRIGGER USER */
2007-11-15 22:14:46 +01:00
ATExecEnableDisableTrigger(rel, NULL,
2011-04-10 17:42:00 +02:00
TRIGGER_FIRES_ON_ORIGIN, true, lockmode);
break;
2005-10-15 04:49:52 +02:00
case AT_DisableTrigUser: /* DISABLE TRIGGER USER */
2007-11-15 22:14:46 +01:00
ATExecEnableDisableTrigger(rel, NULL,
TRIGGER_DISABLED, true, lockmode);
Changes pg_trigger and extend pg_rewrite in order to allow triggers and rules to be defined with different, per session controllable, behaviors for replication purposes. This will allow replication systems like Slony-I and, as has been stated on pgsql-hackers, other products to control the firing mechanism of triggers and rewrite rules without modifying the system catalog directly. The firing mechanisms are controlled by a new superuser-only GUC variable, session_replication_role, together with a change to pg_trigger.tgenabled and a new column pg_rewrite.ev_enabled. Both columns are a single char data type now (tgenabled was a bool before). The possible values in these attributes are: 'O' - Trigger/Rule fires when session_replication_role is "origin" (default) or "local". This is the default behavior. 'D' - Trigger/Rule is disabled and fires never 'A' - Trigger/Rule fires always regardless of the setting of session_replication_role 'R' - Trigger/Rule fires when session_replication_role is "replica" The GUC variable can only be changed as long as the system does not have any cached query plans. This will prevent changing the session role and accidentally executing stored procedures or functions that have plans cached that expand to the wrong query set due to differences in the rule firing semantics. The SQL syntax for changing a triggers/rules firing semantics is ALTER TABLE <tabname> <when> TRIGGER|RULE <name>; <when> ::= ENABLE | ENABLE ALWAYS | ENABLE REPLICA | DISABLE psql's \d command as well as pg_dump are extended in a backward compatible fashion. Jan
2007-03-20 00:38:32 +01:00
break;
2007-11-15 22:14:46 +01:00
case AT_EnableRule: /* ENABLE RULE name */
ATExecEnableDisableRule(rel, cmd->name,
RULE_FIRES_ON_ORIGIN, lockmode);
Changes pg_trigger and extend pg_rewrite in order to allow triggers and rules to be defined with different, per session controllable, behaviors for replication purposes. This will allow replication systems like Slony-I and, as has been stated on pgsql-hackers, other products to control the firing mechanism of triggers and rewrite rules without modifying the system catalog directly. The firing mechanisms are controlled by a new superuser-only GUC variable, session_replication_role, together with a change to pg_trigger.tgenabled and a new column pg_rewrite.ev_enabled. Both columns are a single char data type now (tgenabled was a bool before). The possible values in these attributes are: 'O' - Trigger/Rule fires when session_replication_role is "origin" (default) or "local". This is the default behavior. 'D' - Trigger/Rule is disabled and fires never 'A' - Trigger/Rule fires always regardless of the setting of session_replication_role 'R' - Trigger/Rule fires when session_replication_role is "replica" The GUC variable can only be changed as long as the system does not have any cached query plans. This will prevent changing the session role and accidentally executing stored procedures or functions that have plans cached that expand to the wrong query set due to differences in the rule firing semantics. The SQL syntax for changing a triggers/rules firing semantics is ALTER TABLE <tabname> <when> TRIGGER|RULE <name>; <when> ::= ENABLE | ENABLE ALWAYS | ENABLE REPLICA | DISABLE psql's \d command as well as pg_dump are extended in a backward compatible fashion. Jan
2007-03-20 00:38:32 +01:00
break;
2007-11-15 22:14:46 +01:00
case AT_EnableAlwaysRule: /* ENABLE ALWAYS RULE name */
ATExecEnableDisableRule(rel, cmd->name,
RULE_FIRES_ALWAYS, lockmode);
Changes pg_trigger and extend pg_rewrite in order to allow triggers and rules to be defined with different, per session controllable, behaviors for replication purposes. This will allow replication systems like Slony-I and, as has been stated on pgsql-hackers, other products to control the firing mechanism of triggers and rewrite rules without modifying the system catalog directly. The firing mechanisms are controlled by a new superuser-only GUC variable, session_replication_role, together with a change to pg_trigger.tgenabled and a new column pg_rewrite.ev_enabled. Both columns are a single char data type now (tgenabled was a bool before). The possible values in these attributes are: 'O' - Trigger/Rule fires when session_replication_role is "origin" (default) or "local". This is the default behavior. 'D' - Trigger/Rule is disabled and fires never 'A' - Trigger/Rule fires always regardless of the setting of session_replication_role 'R' - Trigger/Rule fires when session_replication_role is "replica" The GUC variable can only be changed as long as the system does not have any cached query plans. This will prevent changing the session role and accidentally executing stored procedures or functions that have plans cached that expand to the wrong query set due to differences in the rule firing semantics. The SQL syntax for changing a triggers/rules firing semantics is ALTER TABLE <tabname> <when> TRIGGER|RULE <name>; <when> ::= ENABLE | ENABLE ALWAYS | ENABLE REPLICA | DISABLE psql's \d command as well as pg_dump are extended in a backward compatible fashion. Jan
2007-03-20 00:38:32 +01:00
break;
2007-11-15 22:14:46 +01:00
case AT_EnableReplicaRule: /* ENABLE REPLICA RULE name */
ATExecEnableDisableRule(rel, cmd->name,
RULE_FIRES_ON_REPLICA, lockmode);
Changes pg_trigger and extend pg_rewrite in order to allow triggers and rules to be defined with different, per session controllable, behaviors for replication purposes. This will allow replication systems like Slony-I and, as has been stated on pgsql-hackers, other products to control the firing mechanism of triggers and rewrite rules without modifying the system catalog directly. The firing mechanisms are controlled by a new superuser-only GUC variable, session_replication_role, together with a change to pg_trigger.tgenabled and a new column pg_rewrite.ev_enabled. Both columns are a single char data type now (tgenabled was a bool before). The possible values in these attributes are: 'O' - Trigger/Rule fires when session_replication_role is "origin" (default) or "local". This is the default behavior. 'D' - Trigger/Rule is disabled and fires never 'A' - Trigger/Rule fires always regardless of the setting of session_replication_role 'R' - Trigger/Rule fires when session_replication_role is "replica" The GUC variable can only be changed as long as the system does not have any cached query plans. This will prevent changing the session role and accidentally executing stored procedures or functions that have plans cached that expand to the wrong query set due to differences in the rule firing semantics. The SQL syntax for changing a triggers/rules firing semantics is ALTER TABLE <tabname> <when> TRIGGER|RULE <name>; <when> ::= ENABLE | ENABLE ALWAYS | ENABLE REPLICA | DISABLE psql's \d command as well as pg_dump are extended in a backward compatible fashion. Jan
2007-03-20 00:38:32 +01:00
break;
case AT_DisableRule: /* DISABLE RULE name */
2007-11-15 22:14:46 +01:00
ATExecEnableDisableRule(rel, cmd->name,
RULE_DISABLED, lockmode);
break;
Changes pg_trigger and extend pg_rewrite in order to allow triggers and rules to be defined with different, per session controllable, behaviors for replication purposes. This will allow replication systems like Slony-I and, as has been stated on pgsql-hackers, other products to control the firing mechanism of triggers and rewrite rules without modifying the system catalog directly. The firing mechanisms are controlled by a new superuser-only GUC variable, session_replication_role, together with a change to pg_trigger.tgenabled and a new column pg_rewrite.ev_enabled. Both columns are a single char data type now (tgenabled was a bool before). The possible values in these attributes are: 'O' - Trigger/Rule fires when session_replication_role is "origin" (default) or "local". This is the default behavior. 'D' - Trigger/Rule is disabled and fires never 'A' - Trigger/Rule fires always regardless of the setting of session_replication_role 'R' - Trigger/Rule fires when session_replication_role is "replica" The GUC variable can only be changed as long as the system does not have any cached query plans. This will prevent changing the session role and accidentally executing stored procedures or functions that have plans cached that expand to the wrong query set due to differences in the rule firing semantics. The SQL syntax for changing a triggers/rules firing semantics is ALTER TABLE <tabname> <when> TRIGGER|RULE <name>; <when> ::= ENABLE | ENABLE ALWAYS | ENABLE REPLICA | DISABLE psql's \d command as well as pg_dump are extended in a backward compatible fashion. Jan
2007-03-20 00:38:32 +01:00
case AT_AddInherit:
ATExecAddInherit(rel, (RangeVar *) cmd->def, lockmode);
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
break;
case AT_DropInherit:
ATExecDropInherit(rel, (RangeVar *) cmd->def, lockmode);
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
break;
case AT_AddOf:
ATExecAddOf(rel, (TypeName *) cmd->def, lockmode);
break;
case AT_DropOf:
ATExecDropOf(rel, lockmode);
break;
case AT_GenericOptions:
ATExecGenericOptions(rel, (List *) cmd->def);
break;
2004-08-29 07:07:03 +02:00
default: /* oops */
elog(ERROR, "unrecognized alter table type: %d",
(int) cmd->subtype);
break;
}
/*
2005-10-15 04:49:52 +02:00
* Bump the command counter to ensure the next subcommand in the sequence
* can see the changes so far
*/
CommandCounterIncrement();
}
/*
* ATRewriteTables: ALTER TABLE phase 3
*/
static void
ATRewriteTables(List **wqueue, LOCKMODE lockmode)
{
ListCell *ltab;
/* Go through each table that needs to be checked or rewritten */
foreach(ltab, *wqueue)
{
AlteredTableInfo *tab = (AlteredTableInfo *) lfirst(ltab);
/* Foreign tables have no storage. */
if (tab->relkind == RELKIND_FOREIGN_TABLE)
continue;
/*
* If we change column data types or add/remove OIDs, the operation
* has to be propagated to tables that use this table's rowtype as a
* column type. tab->newvals will also be non-NULL in the case where
* we're adding a column with a default. We choose to forbid that
* case as well, since composite types might eventually support
* defaults.
*
* (Eventually we'll probably need to check for composite type
* dependencies even when we're just scanning the table without a
* rewrite, but at the moment a composite type does not enforce any
2011-04-10 17:42:00 +02:00
* constraints, so it's not necessary/appropriate to enforce them just
* during ALTER.)
*/
if (tab->newvals != NIL || tab->rewrite)
{
Relation rel;
rel = heap_open(tab->relid, NoLock);
find_composite_type_dependencies(rel->rd_rel->reltype, rel, NULL);
heap_close(rel, NoLock);
}
/*
2005-10-15 04:49:52 +02:00
* We only need to rewrite the table if at least one column needs to
* be recomputed, or we are adding/removing the OID column.
*/
if (tab->rewrite)
{
/* Build a temporary relation and copy data */
Relation OldHeap;
Oid OIDNewHeap;
Oid NewTableSpace;
OldHeap = heap_open(tab->relid, NoLock);
/*
2010-02-26 03:01:40 +01:00
* We don't support rewriting of system catalogs; there are too
* many corner cases and too little benefit. In particular this
* is certainly not going to work for mapped catalogs.
*/
if (IsSystemRelation(OldHeap))
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot rewrite system relation \"%s\"",
RelationGetRelationName(OldHeap))));
/*
2005-10-15 04:49:52 +02:00
* Don't allow rewrite on temp tables of other backends ... their
* local buffer manager is not going to cope.
*/
if (RELATION_IS_OTHER_TEMP(OldHeap))
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
2005-10-15 04:49:52 +02:00
errmsg("cannot rewrite temporary tables of other sessions")));
/*
* Select destination tablespace (same as original unless user
* requested a change)
*/
if (tab->newTableSpace)
NewTableSpace = tab->newTableSpace;
else
NewTableSpace = OldHeap->rd_rel->reltablespace;
heap_close(OldHeap, NoLock);
/* Create transient table that will receive the modified data */
OIDNewHeap = make_new_heap(tab->relid, NewTableSpace);
/*
* Copy the heap data into the new table with the desired
* modifications, and test the current data within the table
* against new constraints generated by ALTER TABLE commands.
*/
ATRewriteTable(tab, OIDNewHeap, lockmode);
/*
* Swap the physical files of the old and new heaps, then rebuild
* indexes and discard the old heap. We can use RecentXmin for
* the table's new relfrozenxid because we rewrote all the tuples
* in ATRewriteTable, so no older Xid remains in the table. Also,
* we never try to swap toast tables by content, since we have no
* interest in letting this code work on system catalogs.
*/
finish_heap_swap(tab->relid, OIDNewHeap,
false, false, true,
!OidIsValid(tab->newTableSpace),
RecentXmin,
Improve concurrency of foreign key locking This patch introduces two additional lock modes for tuples: "SELECT FOR KEY SHARE" and "SELECT FOR NO KEY UPDATE". These don't block each other, in contrast with already existing "SELECT FOR SHARE" and "SELECT FOR UPDATE". UPDATE commands that do not modify the values stored in the columns that are part of the key of the tuple now grab a SELECT FOR NO KEY UPDATE lock on the tuple, allowing them to proceed concurrently with tuple locks of the FOR KEY SHARE variety. Foreign key triggers now use FOR KEY SHARE instead of FOR SHARE; this means the concurrency improvement applies to them, which is the whole point of this patch. The added tuple lock semantics require some rejiggering of the multixact module, so that the locking level that each transaction is holding can be stored alongside its Xid. Also, multixacts now need to persist across server restarts and crashes, because they can now represent not only tuple locks, but also tuple updates. This means we need more careful tracking of lifetime of pg_multixact SLRU files; since they now persist longer, we require more infrastructure to figure out when they can be removed. pg_upgrade also needs to be careful to copy pg_multixact files over from the old server to the new, or at least part of multixact.c state, depending on the versions of the old and new servers. Tuple time qualification rules (HeapTupleSatisfies routines) need to be careful not to consider tuples with the "is multi" infomask bit set as being only locked; they might need to look up MultiXact values (i.e. possibly do pg_multixact I/O) to find out the Xid that updated a tuple, whereas they previously were assured to only use information readily available from the tuple header. This is considered acceptable, because the extra I/O would involve cases that would previously cause some commands to block waiting for concurrent transactions to finish. Another important change is the fact that locking tuples that have previously been updated causes the future versions to be marked as locked, too; this is essential for correctness of foreign key checks. This causes additional WAL-logging, also (there was previously a single WAL record for a locked tuple; now there are as many as updated copies of the tuple there exist.) With all this in place, contention related to tuples being checked by foreign key rules should be much reduced. As a bonus, the old behavior that a subtransaction grabbing a stronger tuple lock than the parent (sub)transaction held on a given tuple and later aborting caused the weaker lock to be lost, has been fixed. Many new spec files were added for isolation tester framework, to ensure overall behavior is sane. There's probably room for several more tests. There were several reviewers of this patch; in particular, Noah Misch and Andres Freund spent considerable time in it. Original idea for the patch came from Simon Riggs, after a problem report by Joel Jacobson. Most code is from me, with contributions from Marti Raudsepp, Alexander Shulgin, Noah Misch and Andres Freund. This patch was discussed in several pgsql-hackers threads; the most important start at the following message-ids: AANLkTimo9XVcEzfiBR-ut3KVNDkjm2Vxh+t8kAmWjPuv@mail.gmail.com 1290721684-sup-3951@alvh.no-ip.org 1294953201-sup-2099@alvh.no-ip.org 1320343602-sup-2290@alvh.no-ip.org 1339690386-sup-8927@alvh.no-ip.org 4FE5FF020200002500048A3D@gw.wicourts.gov 4FEAB90A0200002500048B7D@gw.wicourts.gov
2013-01-23 16:04:59 +01:00
ReadNextMultiXactId());
}
else
{
/*
2005-10-15 04:49:52 +02:00
* Test the current data within the table against new constraints
* generated by ALTER TABLE commands, but don't rebuild data.
*/
if (tab->constraints != NIL || tab->new_notnull)
ATRewriteTable(tab, InvalidOid, lockmode);
2004-08-29 07:07:03 +02:00
/*
2005-10-15 04:49:52 +02:00
* If we had SET TABLESPACE but no reason to reconstruct tuples,
* just do a block-by-block copy.
*/
if (tab->newTableSpace)
ATExecSetTableSpace(tab->relid, tab->newTableSpace, lockmode);
}
}
/*
2004-08-29 07:07:03 +02:00
* Foreign key constraints are checked in a final pass, since (a) it's
2005-10-15 04:49:52 +02:00
* generally best to examine each one separately, and (b) it's at least
* theoretically possible that we have changed both relations of the
* foreign key, and we'd better have finished both rewrites before we try
* to read the tables.
*/
foreach(ltab, *wqueue)
{
2004-08-29 07:07:03 +02:00
AlteredTableInfo *tab = (AlteredTableInfo *) lfirst(ltab);
Relation rel = NULL;
ListCell *lcon;
foreach(lcon, tab->constraints)
{
NewConstraint *con = lfirst(lcon);
if (con->contype == CONSTR_FOREIGN)
{
Constraint *fkconstraint = (Constraint *) con->qual;
Relation refrel;
if (rel == NULL)
{
/* Long since locked, no need for another */
rel = heap_open(tab->relid, NoLock);
}
refrel = heap_open(con->refrelid, RowShareLock);
validateForeignKeyConstraint(fkconstraint->conname, rel, refrel,
con->refindid,
con->conid);
/*
2011-04-10 17:42:00 +02:00
* No need to mark the constraint row as validated, we did
* that when we inserted the row earlier.
*/
heap_close(refrel, NoLock);
}
}
if (rel)
heap_close(rel, NoLock);
}
}
/*
* ATRewriteTable: scan or rewrite one table
*
* OIDNewHeap is InvalidOid if we don't need to rewrite
*/
static void
ATRewriteTable(AlteredTableInfo *tab, Oid OIDNewHeap, LOCKMODE lockmode)
{
Relation oldrel;
Relation newrel;
TupleDesc oldTupDesc;
TupleDesc newTupDesc;
bool needscan = false;
List *notnull_attrs;
int i;
ListCell *l;
EState *estate;
CommandId mycid;
BulkInsertState bistate;
int hi_options;
/*
* Open the relation(s). We have surely already locked the existing
* table.
*/
oldrel = heap_open(tab->relid, NoLock);
oldTupDesc = tab->oldDesc;
2004-08-29 07:07:03 +02:00
newTupDesc = RelationGetDescr(oldrel); /* includes all mods */
if (OidIsValid(OIDNewHeap))
newrel = heap_open(OIDNewHeap, lockmode);
else
newrel = NULL;
/*
2010-02-26 03:01:40 +01:00
* Prepare a BulkInsertState and options for heap_insert. Because we're
* building a new heap, we can skip WAL-logging and fsync it to disk at
* the end instead (unless WAL-logging is required for archiving or
* streaming replication). The FSM is empty too, so don't bother using it.
*/
if (newrel)
{
mycid = GetCurrentCommandId(true);
bistate = GetBulkInsertState();
hi_options = HEAP_INSERT_SKIP_FSM;
if (!XLogIsNeeded())
hi_options |= HEAP_INSERT_SKIP_WAL;
}
else
{
/* keep compiler quiet about using these uninitialized */
mycid = 0;
bistate = NULL;
hi_options = 0;
}
/*
* Generate the constraint and default execution states
*/
estate = CreateExecutorState();
/* Build the needed expression execution states */
foreach(l, tab->constraints)
{
NewConstraint *con = lfirst(l);
switch (con->contype)
{
case CONSTR_CHECK:
needscan = true;
con->qualstate = (List *)
ExecPrepareExpr((Expr *) con->qual, estate);
break;
case CONSTR_FOREIGN:
/* Nothing to do here */
break;
default:
elog(ERROR, "unrecognized constraint type: %d",
(int) con->contype);
}
}
foreach(l, tab->newvals)
{
2004-08-29 07:07:03 +02:00
NewColumnValue *ex = lfirst(l);
/* expr already planned */
ex->exprstate = ExecInitExpr((Expr *) ex->expr, NULL);
}
notnull_attrs = NIL;
if (newrel || tab->new_notnull)
{
/*
* If we are rebuilding the tuples OR if we added any new NOT NULL
* constraints, check all not-null constraints. This is a bit of
2006-10-04 02:30:14 +02:00
* overkill but it minimizes risk of bugs, and heap_attisnull is a
* pretty cheap test anyway.
*/
for (i = 0; i < newTupDesc->natts; i++)
{
if (newTupDesc->attrs[i]->attnotnull &&
!newTupDesc->attrs[i]->attisdropped)
notnull_attrs = lappend_int(notnull_attrs, i);
}
if (notnull_attrs)
needscan = true;
}
if (newrel || needscan)
{
2004-08-29 07:07:03 +02:00
ExprContext *econtext;
Datum *values;
bool *isnull;
TupleTableSlot *oldslot;
TupleTableSlot *newslot;
2004-08-29 07:07:03 +02:00
HeapScanDesc scan;
HeapTuple tuple;
MemoryContext oldCxt;
2005-10-15 04:49:52 +02:00
List *dropped_attrs = NIL;
ListCell *lc;
if (newrel)
ereport(DEBUG1,
(errmsg("rewriting table \"%s\"",
RelationGetRelationName(oldrel))));
else
ereport(DEBUG1,
(errmsg("verifying table \"%s\"",
RelationGetRelationName(oldrel))));
if (newrel)
{
/*
* All predicate locks on the tuples or pages are about to be made
* invalid, because we move tuples around. Promote them to
* relation locks.
*/
TransferPredicateLocksToHeapRelation(oldrel);
}
econtext = GetPerTupleExprContext(estate);
/*
2005-10-15 04:49:52 +02:00
* Make tuple slots for old and new tuples. Note that even when the
* tuples are the same, the tupDescs might not be (consider ADD COLUMN
* without a default).
*/
oldslot = MakeSingleTupleTableSlot(oldTupDesc);
newslot = MakeSingleTupleTableSlot(newTupDesc);
/* Preallocate values/isnull arrays */
i = Max(newTupDesc->natts, oldTupDesc->natts);
values = (Datum *) palloc(i * sizeof(Datum));
isnull = (bool *) palloc(i * sizeof(bool));
memset(values, 0, i * sizeof(Datum));
memset(isnull, true, i * sizeof(bool));
/*
* Any attributes that are dropped according to the new tuple
2005-10-15 04:49:52 +02:00
* descriptor can be set to NULL. We precompute the list of dropped
* attributes to avoid needing to do so in the per-tuple loop.
*/
for (i = 0; i < newTupDesc->natts; i++)
{
if (newTupDesc->attrs[i]->attisdropped)
dropped_attrs = lappend_int(dropped_attrs, i);
}
/*
* Scan through the rows, generating a new row if needed and then
* checking all the constraints.
*/
scan = heap_beginscan(oldrel, SnapshotNow, 0, NULL);
/*
2005-10-15 04:49:52 +02:00
* Switch to per-tuple memory context and reset it for each tuple
* produced, so we don't leak memory.
*/
oldCxt = MemoryContextSwitchTo(GetPerTupleMemoryContext(estate));
while ((tuple = heap_getnext(scan, ForwardScanDirection)) != NULL)
{
if (tab->rewrite)
{
2005-10-15 04:49:52 +02:00
Oid tupOid = InvalidOid;
/* Extract data from old tuple */
heap_deform_tuple(tuple, oldTupDesc, values, isnull);
if (oldTupDesc->tdhasoid)
tupOid = HeapTupleGetOid(tuple);
/* Set dropped attributes to null in new tuple */
2005-10-15 04:49:52 +02:00
foreach(lc, dropped_attrs)
isnull[lfirst_int(lc)] = true;
/*
2005-10-15 04:49:52 +02:00
* Process supplied expressions to replace selected columns.
* Expression inputs come from the old tuple.
*/
ExecStoreTuple(tuple, oldslot, InvalidBuffer, false);
econtext->ecxt_scantuple = oldslot;
foreach(l, tab->newvals)
{
2004-08-29 07:07:03 +02:00
NewColumnValue *ex = lfirst(l);
values[ex->attnum - 1] = ExecEvalExpr(ex->exprstate,
econtext,
2005-10-15 04:49:52 +02:00
&isnull[ex->attnum - 1],
NULL);
}
/*
2005-10-15 04:49:52 +02:00
* Form the new tuple. Note that we don't explicitly pfree it,
* since the per-tuple memory context will be reset shortly.
*/
tuple = heap_form_tuple(newTupDesc, values, isnull);
/* Preserve OID, if any */
if (newTupDesc->tdhasoid)
HeapTupleSetOid(tuple, tupOid);
}
/* Now check any constraints on the possibly-changed tuple */
ExecStoreTuple(tuple, newslot, InvalidBuffer, false);
econtext->ecxt_scantuple = newslot;
foreach(l, notnull_attrs)
{
2006-10-04 02:30:14 +02:00
int attn = lfirst_int(l);
2006-10-04 02:30:14 +02:00
if (heap_attisnull(tuple, attn + 1))
ereport(ERROR,
(errcode(ERRCODE_NOT_NULL_VIOLATION),
errmsg("column \"%s\" contains null values",
NameStr(newTupDesc->attrs[attn]->attname)),
errtablecol(oldrel, attn + 1)));
}
foreach(l, tab->constraints)
{
NewConstraint *con = lfirst(l);
switch (con->contype)
{
case CONSTR_CHECK:
if (!ExecQual(con->qualstate, econtext, true))
ereport(ERROR,
(errcode(ERRCODE_CHECK_VIOLATION),
errmsg("check constraint \"%s\" is violated by some row",
con->name),
errtableconstraint(oldrel, con->name)));
break;
case CONSTR_FOREIGN:
/* Nothing to do here */
break;
default:
elog(ERROR, "unrecognized constraint type: %d",
(int) con->contype);
}
}
/* Write the tuple out to the new relation */
if (newrel)
heap_insert(newrel, tuple, mycid, hi_options, bistate);
ResetExprContext(econtext);
CHECK_FOR_INTERRUPTS();
}
MemoryContextSwitchTo(oldCxt);
heap_endscan(scan);
ExecDropSingleTupleTableSlot(oldslot);
ExecDropSingleTupleTableSlot(newslot);
}
FreeExecutorState(estate);
heap_close(oldrel, NoLock);
if (newrel)
{
FreeBulkInsertState(bistate);
/* If we skipped writing WAL, then we need to sync the heap. */
if (hi_options & HEAP_INSERT_SKIP_WAL)
heap_sync(newrel);
heap_close(newrel, NoLock);
}
}
/*
* ATGetQueueEntry: find or create an entry in the ALTER TABLE work queue
*/
static AlteredTableInfo *
ATGetQueueEntry(List **wqueue, Relation rel)
{
Oid relid = RelationGetRelid(rel);
AlteredTableInfo *tab;
ListCell *ltab;
foreach(ltab, *wqueue)
{
tab = (AlteredTableInfo *) lfirst(ltab);
if (tab->relid == relid)
return tab;
}
/*
* Not there, so add it. Note that we make a copy of the relation's
* existing descriptor before anything interesting can happen to it.
*/
tab = (AlteredTableInfo *) palloc0(sizeof(AlteredTableInfo));
tab->relid = relid;
tab->relkind = rel->rd_rel->relkind;
tab->oldDesc = CreateTupleDescCopy(RelationGetDescr(rel));
*wqueue = lappend(*wqueue, tab);
return tab;
}
/*
* ATSimplePermissions
*
* - Ensure that it is a relation (or possibly a view)
* - Ensure this user is the owner
* - Ensure that it is not a system table
*/
static void
ATSimplePermissions(Relation rel, int allowed_targets)
{
2011-04-10 17:42:00 +02:00
int actual_target;
switch (rel->rd_rel->relkind)
{
case RELKIND_RELATION:
actual_target = ATT_TABLE;
break;
case RELKIND_VIEW:
actual_target = ATT_VIEW;
break;
case RELKIND_MATVIEW:
actual_target = ATT_MATVIEW;
break;
case RELKIND_INDEX:
actual_target = ATT_INDEX;
break;
case RELKIND_COMPOSITE_TYPE:
actual_target = ATT_COMPOSITE_TYPE;
break;
case RELKIND_FOREIGN_TABLE:
actual_target = ATT_FOREIGN_TABLE;
break;
default:
actual_target = 0;
break;
}
/* Wrong target type? */
if ((actual_target & allowed_targets) == 0)
ATWrongRelkindError(rel, allowed_targets);
/* Permissions checks */
if (!pg_class_ownercheck(RelationGetRelid(rel), GetUserId()))
aclcheck_error(ACLCHECK_NOT_OWNER, ACL_KIND_CLASS,
RelationGetRelationName(rel));
if (!allowSystemTableMods && IsSystemRelation(rel))
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
errmsg("permission denied: \"%s\" is a system catalog",
RelationGetRelationName(rel))));
}
/*
* ATWrongRelkindError
*
* Throw an error when a relation has been determined to be of the wrong
* type.
*/
static void
ATWrongRelkindError(Relation rel, int allowed_targets)
{
char *msg;
switch (allowed_targets)
{
case ATT_TABLE:
msg = _("\"%s\" is not a table");
break;
2011-04-10 17:42:00 +02:00
case ATT_TABLE | ATT_VIEW:
msg = _("\"%s\" is not a table or view");
break;
case ATT_TABLE | ATT_VIEW | ATT_MATVIEW | ATT_INDEX:
msg = _("\"%s\" is not a table, view, materialized view, or index");
break;
case ATT_TABLE | ATT_MATVIEW:
msg = _("\"%s\" is not a table or materialized view");
break;
case ATT_TABLE | ATT_MATVIEW | ATT_INDEX:
msg = _("\"%s\" is not a table, materialized view, or index");
break;
2011-04-10 17:42:00 +02:00
case ATT_TABLE | ATT_FOREIGN_TABLE:
msg = _("\"%s\" is not a table or foreign table");
break;
2011-04-10 17:42:00 +02:00
case ATT_TABLE | ATT_COMPOSITE_TYPE | ATT_FOREIGN_TABLE:
msg = _("\"%s\" is not a table, composite type, or foreign table");
break;
case ATT_TABLE | ATT_MATVIEW | ATT_INDEX | ATT_FOREIGN_TABLE:
msg = _("\"%s\" is not a table, materialized view, composite type, or foreign table");
break;
case ATT_VIEW:
msg = _("\"%s\" is not a view");
break;
case ATT_FOREIGN_TABLE:
msg = _("\"%s\" is not a foreign table");
break;
default:
/* shouldn't get here, add all necessary cases above */
msg = _("\"%s\" is of the wrong type");
break;
}
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg(msg, RelationGetRelationName(rel))));
}
/*
* ATSimpleRecursion
*
* Simple table recursion sufficient for most ALTER TABLE operations.
* All direct and indirect children are processed in an unspecified order.
* Note that if a child inherits from the original table via multiple
* inheritance paths, it will be visited just once.
*/
static void
ATSimpleRecursion(List **wqueue, Relation rel,
AlterTableCmd *cmd, bool recurse, LOCKMODE lockmode)
{
/*
* Propagate to children if desired. Non-table relations never have
* children, so no need to search in that case.
*/
if (recurse && rel->rd_rel->relkind == RELKIND_RELATION)
{
Oid relid = RelationGetRelid(rel);
ListCell *child;
List *children;
children = find_all_inheritors(relid, lockmode, NULL);
/*
2005-10-15 04:49:52 +02:00
* find_all_inheritors does the recursive search of the inheritance
* hierarchy, so all we have to do is process all of the relids in the
* list that it returns.
*/
foreach(child, children)
{
Oid childrelid = lfirst_oid(child);
Relation childrel;
if (childrelid == relid)
continue;
/* find_all_inheritors already got lock */
childrel = relation_open(childrelid, NoLock);
CheckTableNotInUse(childrel, "ALTER TABLE");
ATPrepCmd(wqueue, childrel, cmd, false, true, lockmode);
relation_close(childrel, NoLock);
}
}
}
/*
* ATTypedTableRecursion
*
* Propagate ALTER TYPE operations to the typed tables of that type.
* Also check the RESTRICT/CASCADE behavior. Given CASCADE, also permit
* recursion to inheritance children of the typed tables.
*/
static void
ATTypedTableRecursion(List **wqueue, Relation rel, AlterTableCmd *cmd,
LOCKMODE lockmode)
{
ListCell *child;
List *children;
Assert(rel->rd_rel->relkind == RELKIND_COMPOSITE_TYPE);
children = find_typed_table_dependencies(rel->rd_rel->reltype,
RelationGetRelationName(rel),
cmd->behavior);
foreach(child, children)
{
Oid childrelid = lfirst_oid(child);
Relation childrel;
childrel = relation_open(childrelid, lockmode);
CheckTableNotInUse(childrel, "ALTER TABLE");
ATPrepCmd(wqueue, childrel, cmd, true, true, lockmode);
relation_close(childrel, NoLock);
}
}
/*
* find_composite_type_dependencies
*
* Check to see if a composite type is being used as a column in some
* other table (possibly nested several levels deep in composite types!).
* Eventually, we'd like to propagate the check or rewrite operation
* into other such tables, but for now, just error out if we find any.
*
* Caller should provide either a table name or a type name (not both) to
* report in the error message, if any.
*
* We assume that functions and views depending on the type are not reasons
* to reject the ALTER. (How safe is this really?)
*/
void
find_composite_type_dependencies(Oid typeOid, Relation origRelation,
const char *origTypeName)
{
Relation depRel;
ScanKeyData key[2];
SysScanDesc depScan;
HeapTuple depTup;
Oid arrayOid;
/*
2005-10-15 04:49:52 +02:00
* We scan pg_depend to find those things that depend on the rowtype. (We
* assume we can ignore refobjsubid for a rowtype.)
*/
depRel = heap_open(DependRelationId, AccessShareLock);
ScanKeyInit(&key[0],
Anum_pg_depend_refclassid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(TypeRelationId));
ScanKeyInit(&key[1],
Anum_pg_depend_refobjid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(typeOid));
depScan = systable_beginscan(depRel, DependReferenceIndexId, true,
SnapshotNow, 2, key);
while (HeapTupleIsValid(depTup = systable_getnext(depScan)))
{
Form_pg_depend pg_depend = (Form_pg_depend) GETSTRUCT(depTup);
Relation rel;
Form_pg_attribute att;
/* Ignore dependees that aren't user columns of relations */
/* (we assume system columns are never of rowtypes) */
if (pg_depend->classid != RelationRelationId ||
pg_depend->objsubid <= 0)
continue;
rel = relation_open(pg_depend->objid, AccessShareLock);
att = rel->rd_att->attrs[pg_depend->objsubid - 1];
if (rel->rd_rel->relkind == RELKIND_RELATION ||
rel->rd_rel->relkind == RELKIND_MATVIEW)
{
if (origTypeName)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot alter type \"%s\" because column \"%s.%s\" uses it",
origTypeName,
RelationGetRelationName(rel),
NameStr(att->attname))));
else if (origRelation->rd_rel->relkind == RELKIND_COMPOSITE_TYPE)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot alter type \"%s\" because column \"%s.%s\" uses it",
RelationGetRelationName(origRelation),
RelationGetRelationName(rel),
NameStr(att->attname))));
else if (origRelation->rd_rel->relkind == RELKIND_FOREIGN_TABLE)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot alter foreign table \"%s\" because column \"%s.%s\" uses its row type",
RelationGetRelationName(origRelation),
RelationGetRelationName(rel),
NameStr(att->attname))));
else
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot alter table \"%s\" because column \"%s.%s\" uses its row type",
RelationGetRelationName(origRelation),
RelationGetRelationName(rel),
NameStr(att->attname))));
}
else if (OidIsValid(rel->rd_rel->reltype))
{
/*
2005-10-15 04:49:52 +02:00
* A view or composite type itself isn't a problem, but we must
* recursively check for indirect dependencies via its rowtype.
*/
find_composite_type_dependencies(rel->rd_rel->reltype,
origRelation, origTypeName);
}
relation_close(rel, AccessShareLock);
}
systable_endscan(depScan);
relation_close(depRel, AccessShareLock);
/*
* If there's an array type for the rowtype, must check for uses of it,
* too.
*/
arrayOid = get_array_type(typeOid);
if (OidIsValid(arrayOid))
find_composite_type_dependencies(arrayOid, origRelation, origTypeName);
}
/*
* find_typed_table_dependencies
*
* Check to see if a composite type is being used as the type of a
* typed table. Abort if any are found and behavior is RESTRICT.
* Else return the list of tables.
*/
static List *
find_typed_table_dependencies(Oid typeOid, const char *typeName, DropBehavior behavior)
{
Relation classRel;
ScanKeyData key[1];
HeapScanDesc scan;
HeapTuple tuple;
List *result = NIL;
classRel = heap_open(RelationRelationId, AccessShareLock);
ScanKeyInit(&key[0],
Anum_pg_class_reloftype,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(typeOid));
scan = heap_beginscan(classRel, SnapshotNow, 1, key);
while ((tuple = heap_getnext(scan, ForwardScanDirection)) != NULL)
{
if (behavior == DROP_RESTRICT)
ereport(ERROR,
(errcode(ERRCODE_DEPENDENT_OBJECTS_STILL_EXIST),
errmsg("cannot alter type \"%s\" because it is the type of a typed table",
typeName),
2011-04-10 17:42:00 +02:00
errhint("Use ALTER ... CASCADE to alter the typed tables too.")));
else
result = lappend_oid(result, HeapTupleGetOid(tuple));
}
heap_endscan(scan);
heap_close(classRel, AccessShareLock);
return result;
}
/*
* check_of_type
*
* Check whether a type is suitable for CREATE TABLE OF/ALTER TABLE OF. If it
* isn't suitable, throw an error. Currently, we require that the type
2011-06-09 20:32:50 +02:00
* originated with CREATE TYPE AS. We could support any row type, but doing so
* would require handling a number of extra corner cases in the DDL commands.
*/
void
check_of_type(HeapTuple typetuple)
{
Form_pg_type typ = (Form_pg_type) GETSTRUCT(typetuple);
bool typeOk = false;
if (typ->typtype == TYPTYPE_COMPOSITE)
{
Relation typeRelation;
Assert(OidIsValid(typ->typrelid));
typeRelation = relation_open(typ->typrelid, AccessShareLock);
typeOk = (typeRelation->rd_rel->relkind == RELKIND_COMPOSITE_TYPE);
2011-06-09 20:32:50 +02:00
/*
* Close the parent rel, but keep our AccessShareLock on it until xact
* commit. That will prevent someone else from deleting or ALTERing
* the type before the typed table creation/conversion commits.
*/
relation_close(typeRelation, NoLock);
}
if (!typeOk)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("type %s is not a composite type",
format_type_be(HeapTupleGetOid(typetuple)))));
}
/*
* ALTER TABLE ADD COLUMN
*
* Adds an additional attribute to a relation making the assumption that
* CHECK, NOT NULL, and FOREIGN KEY constraints will be removed from the
* AT_AddColumn AlterTableCmd by parse_utilcmd.c and added as independent
* AlterTableCmd's.
*
* ADD COLUMN cannot use the normal ALTER TABLE recursion mechanism, because we
* have to decide at runtime whether to recurse or not depending on whether we
* actually add a column or merely merge with an existing column. (We can't
* check this in a static pre-pass because it won't handle multiple inheritance
* situations correctly.)
*/
static void
ATPrepAddColumn(List **wqueue, Relation rel, bool recurse, bool recursing,
AlterTableCmd *cmd, LOCKMODE lockmode)
{
if (rel->rd_rel->reloftype && !recursing)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("cannot add column to typed table")));
if (rel->rd_rel->relkind == RELKIND_COMPOSITE_TYPE)
ATTypedTableRecursion(wqueue, rel, cmd, lockmode);
if (recurse)
cmd->subtype = AT_AddColumnRecurse;
}
static void
ATExecAddColumn(List **wqueue, AlteredTableInfo *tab, Relation rel,
ColumnDef *colDef, bool isOid,
bool recurse, bool recursing, LOCKMODE lockmode)
{
Oid myrelid = RelationGetRelid(rel);
Relation pgclass,
attrdesc;
HeapTuple reltup;
FormData_pg_attribute attribute;
int newattnum;
char relkind;
HeapTuple typeTuple;
Oid typeOid;
int32 typmod;
Oid collOid;
Form_pg_type tform;
Expr *defval;
List *children;
ListCell *child;
AclResult aclresult;
/* At top level, permission check was done in ATPrepCmd, else do it */
if (recursing)
ATSimplePermissions(rel, ATT_TABLE);
attrdesc = heap_open(AttributeRelationId, RowExclusiveLock);
/*
2005-10-15 04:49:52 +02:00
* Are we adding the column to a recursion child? If so, check whether to
2011-04-10 17:42:00 +02:00
* merge with an existing definition for the column. If we do merge, we
* must not recurse. Children will already have the column, and recursing
* into them would mess up attinhcount.
*/
if (colDef->inhcount > 0)
{
HeapTuple tuple;
/* Does child already have a column by this name? */
tuple = SearchSysCacheCopyAttName(myrelid, colDef->colname);
if (HeapTupleIsValid(tuple))
{
Form_pg_attribute childatt = (Form_pg_attribute) GETSTRUCT(tuple);
2007-11-15 22:14:46 +01:00
Oid ctypeId;
int32 ctypmod;
Oid ccollid;
/* Child column must match on type, typmod, and collation */
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
typenameTypeIdAndMod(NULL, colDef->typeName, &ctypeId, &ctypmod);
if (ctypeId != childatt->atttypid ||
ctypmod != childatt->atttypmod)
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
errmsg("child table \"%s\" has different type for column \"%s\"",
2005-10-15 04:49:52 +02:00
RelationGetRelationName(rel), colDef->colname)));
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
ccollid = GetColumnDefCollation(NULL, colDef, ctypeId);
if (ccollid != childatt->attcollation)
ereport(ERROR,
(errcode(ERRCODE_COLLATION_MISMATCH),
errmsg("child table \"%s\" has different collation for column \"%s\"",
2011-04-10 17:42:00 +02:00
RelationGetRelationName(rel), colDef->colname),
errdetail("\"%s\" versus \"%s\"",
get_collation_name(ccollid),
2011-04-10 17:42:00 +02:00
get_collation_name(childatt->attcollation))));
/* If it's OID, child column must actually be OID */
if (isOid && childatt->attnum != ObjectIdAttributeNumber)
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
errmsg("child table \"%s\" has a conflicting \"%s\" column",
RelationGetRelationName(rel), colDef->colname)));
/* Bump the existing child att's inhcount */
childatt->attinhcount++;
simple_heap_update(attrdesc, &tuple->t_self, tuple);
CatalogUpdateIndexes(attrdesc, tuple);
heap_freetuple(tuple);
/* Inform the user about the merge */
ereport(NOTICE,
2005-10-15 04:49:52 +02:00
(errmsg("merging definition of column \"%s\" for child \"%s\"",
colDef->colname, RelationGetRelationName(rel))));
heap_close(attrdesc, RowExclusiveLock);
return;
}
}
pgclass = heap_open(RelationRelationId, RowExclusiveLock);
reltup = SearchSysCacheCopy1(RELOID, ObjectIdGetDatum(myrelid));
if (!HeapTupleIsValid(reltup))
elog(ERROR, "cache lookup failed for relation %u", myrelid);
relkind = ((Form_pg_class) GETSTRUCT(reltup))->relkind;
/* new name should not already exist */
check_for_column_name_collision(rel, colDef->colname);
/* Determine the new attribute's number */
if (isOid)
newattnum = ObjectIdAttributeNumber;
else
{
newattnum = ((Form_pg_class) GETSTRUCT(reltup))->relnatts + 1;
if (newattnum > MaxHeapAttributeNumber)
ereport(ERROR,
(errcode(ERRCODE_TOO_MANY_COLUMNS),
errmsg("tables can have at most %d columns",
MaxHeapAttributeNumber)));
}
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
typeTuple = typenameType(NULL, colDef->typeName, &typmod);
tform = (Form_pg_type) GETSTRUCT(typeTuple);
typeOid = HeapTupleGetOid(typeTuple);
aclresult = pg_type_aclcheck(typeOid, GetUserId(), ACL_USAGE);
if (aclresult != ACLCHECK_OK)
aclcheck_error_type(aclresult, typeOid);
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
collOid = GetColumnDefCollation(NULL, colDef, typeOid);
/* make sure datatype is legal for a column */
CheckAttributeType(colDef->colname, typeOid, collOid,
list_make1_oid(rel->rd_rel->reltype),
false);
/* construct new attribute's pg_attribute entry */
attribute.attrelid = myrelid;
namestrcpy(&(attribute.attname), colDef->colname);
attribute.atttypid = typeOid;
attribute.attstattarget = (newattnum > 0) ? -1 : 0;
attribute.attlen = tform->typlen;
attribute.attcacheoff = -1;
attribute.atttypmod = typmod;
attribute.attnum = newattnum;
attribute.attbyval = tform->typbyval;
attribute.attndims = list_length(colDef->typeName->arrayBounds);
attribute.attstorage = tform->typstorage;
attribute.attalign = tform->typalign;
attribute.attnotnull = colDef->is_not_null;
attribute.atthasdef = false;
attribute.attisdropped = false;
attribute.attislocal = colDef->is_local;
attribute.attinhcount = colDef->inhcount;
attribute.attcollation = collOid;
/* attribute.attacl is handled by InsertPgAttributeTuple */
ReleaseSysCache(typeTuple);
InsertPgAttributeTuple(attrdesc, &attribute, NULL);
heap_close(attrdesc, RowExclusiveLock);
/*
* Update pg_class tuple as appropriate
*/
if (isOid)
((Form_pg_class) GETSTRUCT(reltup))->relhasoids = true;
else
((Form_pg_class) GETSTRUCT(reltup))->relnatts = newattnum;
simple_heap_update(pgclass, &reltup->t_self, reltup);
/* keep catalog indexes current */
CatalogUpdateIndexes(pgclass, reltup);
heap_freetuple(reltup);
/* Post creation hook for new attribute */
InvokeObjectPostCreateHook(RelationRelationId, myrelid, newattnum);
heap_close(pgclass, RowExclusiveLock);
/* Make the attribute's catalog entry visible */
CommandCounterIncrement();
/*
* Store the DEFAULT, if any, in the catalogs
*/
if (colDef->raw_default)
{
RawColumnDefault *rawEnt;
rawEnt = (RawColumnDefault *) palloc(sizeof(RawColumnDefault));
rawEnt->attnum = attribute.attnum;
rawEnt->raw_default = copyObject(colDef->raw_default);
/*
* This function is intended for CREATE TABLE, so it processes a
* _list_ of defaults, but we just do one.
*/
AddRelationNewConstraints(rel, list_make1(rawEnt), NIL,
false, true, false);
/* Make the additional catalog changes visible */
CommandCounterIncrement();
}
/*
* Tell Phase 3 to fill in the default expression, if there is one.
*
* If there is no default, Phase 3 doesn't have to do anything, because
* that effectively means that the default is NULL. The heap tuple access
2005-10-15 04:49:52 +02:00
* routines always check for attnum > # of attributes in tuple, and return
* NULL if so, so without any modification of the tuple data we will get
* the effect of NULL values in the new column.
*
2005-10-15 04:49:52 +02:00
* An exception occurs when the new column is of a domain type: the domain
* might have a NOT NULL constraint, or a check constraint that indirectly
* rejects nulls. If there are any domain constraints then we construct
* an explicit NULL default value that will be passed through
* CoerceToDomain processing. (This is a tad inefficient, since it causes
* rewriting the table which we really don't have to do, but the present
* design of domain processing doesn't offer any simple way of checking
* the constraints more directly.)
*
* Note: we use build_column_default, and not just the cooked default
* returned by AddRelationNewConstraints, so that the right thing happens
2005-10-15 04:49:52 +02:00
* when a datatype's default applies.
*
* We skip this step completely for views and foreign tables. For a view,
* we can only get here from CREATE OR REPLACE VIEW, which historically
* doesn't set up defaults, not even for domain-typed columns. And in any
* case we mustn't invoke Phase 3 on a view or foreign table, since they
* have no storage.
*/
if (relkind != RELKIND_VIEW && relkind != RELKIND_COMPOSITE_TYPE
&& relkind != RELKIND_FOREIGN_TABLE && attribute.attnum > 0)
{
defval = (Expr *) build_column_default(rel, attribute.attnum);
if (!defval && GetDomainConstraints(typeOid) != NIL)
{
Oid baseTypeId;
int32 baseTypeMod;
Oid baseTypeColl;
baseTypeMod = typmod;
baseTypeId = getBaseTypeAndTypmod(typeOid, &baseTypeMod);
baseTypeColl = get_typcollation(baseTypeId);
defval = (Expr *) makeNullConst(baseTypeId, baseTypeMod, baseTypeColl);
defval = (Expr *) coerce_to_target_type(NULL,
(Node *) defval,
baseTypeId,
typeOid,
typmod,
COERCION_ASSIGNMENT,
COERCE_IMPLICIT_CAST,
-1);
if (defval == NULL) /* should not happen */
elog(ERROR, "failed to coerce base type to domain");
}
if (defval)
{
NewColumnValue *newval;
newval = (NewColumnValue *) palloc0(sizeof(NewColumnValue));
newval->attnum = attribute.attnum;
newval->expr = expression_planner(defval);
tab->newvals = lappend(tab->newvals, newval);
tab->rewrite = true;
}
/*
* If the new column is NOT NULL, tell Phase 3 it needs to test that.
* (Note we don't do this for an OID column. OID will be marked not
* null, but since it's filled specially, there's no need to test
* anything.)
*/
tab->new_notnull |= colDef->is_not_null;
}
/*
* If we are adding an OID column, we have to tell Phase 3 to rewrite the
* table to fix that.
*/
if (isOid)
tab->rewrite = true;
/*
* Add needed dependency entries for the new column.
*/
add_column_datatype_dependency(myrelid, newattnum, attribute.atttypid);
add_column_collation_dependency(myrelid, newattnum, attribute.attcollation);
/*
* Propagate to children as appropriate. Unlike most other ALTER
* routines, we have to do this one level of recursion at a time; we can't
* use find_all_inheritors to do it in one pass.
*/
children = find_inheritance_children(RelationGetRelid(rel), lockmode);
/*
* If we are told not to recurse, there had better not be any child
* tables; else the addition would put them out of step.
*/
if (children && !recurse)
ereport(ERROR,
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
errmsg("column must be added to child tables too")));
/* Children should see column as singly inherited */
if (!recursing)
{
colDef = copyObject(colDef);
colDef->inhcount = 1;
colDef->is_local = false;
}
foreach(child, children)
{
Oid childrelid = lfirst_oid(child);
Relation childrel;
AlteredTableInfo *childtab;
/* find_inheritance_children already got lock */
childrel = heap_open(childrelid, NoLock);
CheckTableNotInUse(childrel, "ALTER TABLE");
/* Find or create work queue entry for this table */
childtab = ATGetQueueEntry(wqueue, childrel);
/* Recurse to child */
ATExecAddColumn(wqueue, childtab, childrel,
colDef, isOid, recurse, true, lockmode);
heap_close(childrel, NoLock);
}
}
/*
* If a new or renamed column will collide with the name of an existing
* column, error out.
*/
static void
check_for_column_name_collision(Relation rel, const char *colname)
{
HeapTuple attTuple;
int attnum;
/*
* this test is deliberately not attisdropped-aware, since if one tries to
* add a column matching a dropped column name, it's gonna fail anyway.
*/
attTuple = SearchSysCache2(ATTNAME,
ObjectIdGetDatum(RelationGetRelid(rel)),
PointerGetDatum(colname));
if (!HeapTupleIsValid(attTuple))
return;
attnum = ((Form_pg_attribute) GETSTRUCT(attTuple))->attnum;
ReleaseSysCache(attTuple);
/*
* We throw a different error message for conflicts with system column
* names, since they are normally not shown and the user might otherwise
* be confused about the reason for the conflict.
*/
if (attnum <= 0)
ereport(ERROR,
(errcode(ERRCODE_DUPLICATE_COLUMN),
errmsg("column name \"%s\" conflicts with a system column name",
colname)));
else
ereport(ERROR,
(errcode(ERRCODE_DUPLICATE_COLUMN),
errmsg("column \"%s\" of relation \"%s\" already exists",
colname, RelationGetRelationName(rel))));
}
/*
* Install a column's dependency on its datatype.
*/
static void
add_column_datatype_dependency(Oid relid, int32 attnum, Oid typid)
{
ObjectAddress myself,
referenced;
myself.classId = RelationRelationId;
myself.objectId = relid;
myself.objectSubId = attnum;
referenced.classId = TypeRelationId;
referenced.objectId = typid;
referenced.objectSubId = 0;
recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
}
/*
* Install a column's dependency on its collation.
*/
static void
add_column_collation_dependency(Oid relid, int32 attnum, Oid collid)
{
ObjectAddress myself,
referenced;
/* We know the default collation is pinned, so don't bother recording it */
if (OidIsValid(collid) && collid != DEFAULT_COLLATION_OID)
{
myself.classId = RelationRelationId;
myself.objectId = relid;
myself.objectSubId = attnum;
referenced.classId = CollationRelationId;
referenced.objectId = collid;
referenced.objectSubId = 0;
recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
}
}
/*
* ALTER TABLE SET WITH OIDS
*
* Basically this is an ADD COLUMN for the special OID column. We have
* to cons up a ColumnDef node because the ADD COLUMN code needs one.
*/
static void
ATPrepAddOids(List **wqueue, Relation rel, bool recurse, AlterTableCmd *cmd, LOCKMODE lockmode)
{
/* If we're recursing to a child table, the ColumnDef is already set up */
if (cmd->def == NULL)
{
ColumnDef *cdef = makeNode(ColumnDef);
cdef->colname = pstrdup("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
cdef->typeName = makeTypeNameFromOid(OIDOID, -1);
cdef->inhcount = 0;
cdef->is_local = true;
cdef->is_not_null = true;
cdef->storage = 0;
cmd->def = (Node *) cdef;
}
ATPrepAddColumn(wqueue, rel, recurse, false, cmd, lockmode);
if (recurse)
cmd->subtype = AT_AddOidsRecurse;
}
/*
* ALTER TABLE ALTER COLUMN DROP NOT NULL
*/
static void
ATExecDropNotNull(Relation rel, const char *colName, LOCKMODE lockmode)
{
HeapTuple tuple;
AttrNumber attnum;
Relation attr_rel;
List *indexoidlist;
ListCell *indexoidscan;
/*
* lookup the attribute
*/
attr_rel = heap_open(AttributeRelationId, RowExclusiveLock);
tuple = SearchSysCacheCopyAttName(RelationGetRelid(rel), colName);
if (!HeapTupleIsValid(tuple))
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_COLUMN),
errmsg("column \"%s\" of relation \"%s\" does not exist",
colName, RelationGetRelationName(rel))));
attnum = ((Form_pg_attribute) GETSTRUCT(tuple))->attnum;
/* Prevent them from altering a system attribute */
if (attnum <= 0)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot alter system column \"%s\"",
colName)));
/*
* Check that the attribute is not in a primary key
Fix assorted bugs in CREATE/DROP INDEX CONCURRENTLY. Commit 8cb53654dbdb4c386369eb988062d0bbb6de725e, which introduced DROP INDEX CONCURRENTLY, managed to break CREATE INDEX CONCURRENTLY via a poor choice of catalog state representation. The pg_index state for an index that's reached the final pre-drop stage was the same as the state for an index just created by CREATE INDEX CONCURRENTLY. This meant that the (necessary) change to make RelationGetIndexList ignore about-to-die indexes also made it ignore freshly-created indexes; which is catastrophic because the latter do need to be considered in HOT-safety decisions. Failure to do so leads to incorrect index entries and subsequently wrong results from queries depending on the concurrently-created index. To fix, add an additional boolean column "indislive" to pg_index, so that the freshly-created and about-to-die states can be distinguished. (This change obviously is only possible in HEAD. This patch will need to be back-patched, but in 9.2 we'll use a kluge consisting of overloading the formerly-impossible state of indisvalid = true and indisready = false.) In addition, change CREATE/DROP INDEX CONCURRENTLY so that the pg_index flag changes they make without exclusive lock on the index are made via heap_inplace_update() rather than a normal transactional update. The latter is not very safe because moving the pg_index tuple could result in concurrent SnapshotNow scans finding it twice or not at all, thus possibly resulting in index corruption. This is a pre-existing bug in CREATE INDEX CONCURRENTLY, which was copied into the DROP code. In addition, fix various places in the code that ought to check to make sure that the indexes they are manipulating are valid and/or ready as appropriate. These represent bugs that have existed since 8.2, since a failed CREATE INDEX CONCURRENTLY could leave a corrupt or invalid index behind, and we ought not try to do anything that might fail with such an index. Also fix RelationReloadIndexInfo to ensure it copies all the pg_index columns that are allowed to change after initial creation. Previously we could have been left with stale values of some fields in an index relcache entry. It's not clear whether this actually had any user-visible consequences, but it's at least a bug waiting to happen. In addition, do some code and docs review for DROP INDEX CONCURRENTLY; some cosmetic code cleanup but mostly addition and revision of comments. This will need to be back-patched, but in a noticeably different form, so I'm committing it to HEAD before working on the back-patch. Problem reported by Amit Kapila, diagnosis by Pavan Deolassee, fix by Tom Lane and Andres Freund.
2012-11-29 03:25:27 +01:00
*
* Note: we'll throw error even if the pkey index is not valid.
*/
/* Loop over all indexes on the relation */
indexoidlist = RelationGetIndexList(rel);
foreach(indexoidscan, indexoidlist)
{
Oid indexoid = lfirst_oid(indexoidscan);
HeapTuple indexTuple;
Form_pg_index indexStruct;
int i;
indexTuple = SearchSysCache1(INDEXRELID, ObjectIdGetDatum(indexoid));
if (!HeapTupleIsValid(indexTuple))
elog(ERROR, "cache lookup failed for index %u", indexoid);
indexStruct = (Form_pg_index) GETSTRUCT(indexTuple);
/* If the index is not a primary key, skip the check */
if (indexStruct->indisprimary)
{
/*
* Loop over each attribute in the primary key and see if it
* matches the to-be-altered attribute
*/
for (i = 0; i < indexStruct->indnatts; i++)
{
if (indexStruct->indkey.values[i] == attnum)
ereport(ERROR,
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
2004-08-29 07:07:03 +02:00
errmsg("column \"%s\" is in a primary key",
colName)));
}
}
ReleaseSysCache(indexTuple);
}
list_free(indexoidlist);
/*
* Okay, actually perform the catalog change ... if needed
*/
if (((Form_pg_attribute) GETSTRUCT(tuple))->attnotnull)
{
((Form_pg_attribute) GETSTRUCT(tuple))->attnotnull = FALSE;
simple_heap_update(attr_rel, &tuple->t_self, tuple);
/* keep the system catalog indexes current */
CatalogUpdateIndexes(attr_rel, tuple);
}
InvokeObjectPostAlterHook(RelationRelationId,
RelationGetRelid(rel), attnum);
heap_close(attr_rel, RowExclusiveLock);
}
/*
* ALTER TABLE ALTER COLUMN SET NOT NULL
*/
static void
ATExecSetNotNull(AlteredTableInfo *tab, Relation rel,
const char *colName, LOCKMODE lockmode)
{
HeapTuple tuple;
AttrNumber attnum;
Relation attr_rel;
/*
* lookup the attribute
*/
attr_rel = heap_open(AttributeRelationId, RowExclusiveLock);
tuple = SearchSysCacheCopyAttName(RelationGetRelid(rel), colName);
if (!HeapTupleIsValid(tuple))
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_COLUMN),
errmsg("column \"%s\" of relation \"%s\" does not exist",
colName, RelationGetRelationName(rel))));
attnum = ((Form_pg_attribute) GETSTRUCT(tuple))->attnum;
/* Prevent them from altering a system attribute */
if (attnum <= 0)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot alter system column \"%s\"",
colName)));
2002-09-04 22:31:48 +02:00
/*
* Okay, actually perform the catalog change ... if needed
*/
2004-08-29 07:07:03 +02:00
if (!((Form_pg_attribute) GETSTRUCT(tuple))->attnotnull)
{
((Form_pg_attribute) GETSTRUCT(tuple))->attnotnull = TRUE;
simple_heap_update(attr_rel, &tuple->t_self, tuple);
/* keep the system catalog indexes current */
CatalogUpdateIndexes(attr_rel, tuple);
/* Tell Phase 3 it needs to test the constraint */
tab->new_notnull = true;
}
InvokeObjectPostAlterHook(RelationRelationId,
RelationGetRelid(rel), attnum);
heap_close(attr_rel, RowExclusiveLock);
}
/*
* ALTER TABLE ALTER COLUMN SET/DROP DEFAULT
*/
static void
ATExecColumnDefault(Relation rel, const char *colName,
Node *newDefault, LOCKMODE lockmode)
{
AttrNumber attnum;
/*
* get the number of the attribute
*/
attnum = get_attnum(RelationGetRelid(rel), colName);
if (attnum == InvalidAttrNumber)
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_COLUMN),
2004-08-29 07:07:03 +02:00
errmsg("column \"%s\" of relation \"%s\" does not exist",
colName, RelationGetRelationName(rel))));
/* Prevent them from altering a system attribute */
if (attnum <= 0)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot alter system column \"%s\"",
colName)));
/*
* Remove any old default for the column. We use RESTRICT here for
* safety, but at present we do not expect anything to depend on the
* default.
*
* We treat removing the existing default as an internal operation when it
* is preparatory to adding a new default, but as a user-initiated
* operation when the user asked for a drop.
*/
RemoveAttrDefault(RelationGetRelid(rel), attnum, DROP_RESTRICT, false,
newDefault == NULL ? false : true);
if (newDefault)
{
/* SET DEFAULT */
RawColumnDefault *rawEnt;
rawEnt = (RawColumnDefault *) palloc(sizeof(RawColumnDefault));
rawEnt->attnum = attnum;
rawEnt->raw_default = newDefault;
/*
* This function is intended for CREATE TABLE, so it processes a
* _list_ of defaults, but we just do one.
*/
AddRelationNewConstraints(rel, list_make1(rawEnt), NIL,
false, true, false);
}
}
/*
* ALTER TABLE ALTER COLUMN SET STATISTICS
*/
static void
ATPrepSetStatistics(Relation rel, const char *colName, Node *newValue, LOCKMODE lockmode)
{
/*
2004-08-29 07:07:03 +02:00
* We do our own permission checking because (a) we want to allow SET
2005-10-15 04:49:52 +02:00
* STATISTICS on indexes (for expressional index columns), and (b) we want
* to allow SET STATISTICS on system catalogs without requiring
2004-08-29 07:07:03 +02:00
* allowSystemTableMods to be turned on.
*/
if (rel->rd_rel->relkind != RELKIND_RELATION &&
rel->rd_rel->relkind != RELKIND_MATVIEW &&
rel->rd_rel->relkind != RELKIND_INDEX &&
rel->rd_rel->relkind != RELKIND_FOREIGN_TABLE)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("\"%s\" is not a table, materialized view, index, or foreign table",
RelationGetRelationName(rel))));
/* Permissions checks */
if (!pg_class_ownercheck(RelationGetRelid(rel), GetUserId()))
aclcheck_error(ACLCHECK_NOT_OWNER, ACL_KIND_CLASS,
RelationGetRelationName(rel));
}
static void
ATExecSetStatistics(Relation rel, const char *colName, Node *newValue, LOCKMODE lockmode)
{
int newtarget;
Relation attrelation;
HeapTuple tuple;
Form_pg_attribute attrtuple;
Assert(IsA(newValue, Integer));
newtarget = intVal(newValue);
/*
* Limit target to a sane range
*/
if (newtarget < -1)
{
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("statistics target %d is too low",
newtarget)));
}
else if (newtarget > 10000)
{
newtarget = 10000;
ereport(WARNING,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("lowering statistics target to %d",
newtarget)));
}
attrelation = heap_open(AttributeRelationId, RowExclusiveLock);
tuple = SearchSysCacheCopyAttName(RelationGetRelid(rel), colName);
if (!HeapTupleIsValid(tuple))
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_COLUMN),
2004-08-29 07:07:03 +02:00
errmsg("column \"%s\" of relation \"%s\" does not exist",
colName, RelationGetRelationName(rel))));
attrtuple = (Form_pg_attribute) GETSTRUCT(tuple);
if (attrtuple->attnum <= 0)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot alter system column \"%s\"",
colName)));
attrtuple->attstattarget = newtarget;
simple_heap_update(attrelation, &tuple->t_self, tuple);
/* keep system catalog indexes current */
CatalogUpdateIndexes(attrelation, tuple);
InvokeObjectPostAlterHook(RelationRelationId,
RelationGetRelid(rel),
attrtuple->attnum);
heap_freetuple(tuple);
heap_close(attrelation, RowExclusiveLock);
}
static void
ATExecSetOptions(Relation rel, const char *colName, Node *options,
bool isReset, LOCKMODE lockmode)
{
Relation attrelation;
HeapTuple tuple,
newtuple;
Form_pg_attribute attrtuple;
Datum datum,
newOptions;
bool isnull;
Datum repl_val[Natts_pg_attribute];
bool repl_null[Natts_pg_attribute];
bool repl_repl[Natts_pg_attribute];
attrelation = heap_open(AttributeRelationId, RowExclusiveLock);
tuple = SearchSysCacheAttName(RelationGetRelid(rel), colName);
if (!HeapTupleIsValid(tuple))
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_COLUMN),
errmsg("column \"%s\" of relation \"%s\" does not exist",
colName, RelationGetRelationName(rel))));
attrtuple = (Form_pg_attribute) GETSTRUCT(tuple);
if (attrtuple->attnum <= 0)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot alter system column \"%s\"",
colName)));
/* Generate new proposed attoptions (text array) */
Assert(IsA(options, List));
datum = SysCacheGetAttr(ATTNAME, tuple, Anum_pg_attribute_attoptions,
2010-02-26 03:01:40 +01:00
&isnull);
newOptions = transformRelOptions(isnull ? (Datum) 0 : datum,
(List *) options, NULL, NULL, false,
isReset);
/* Validate new options */
(void) attribute_reloptions(newOptions, true);
/* Build new tuple. */
memset(repl_null, false, sizeof(repl_null));
memset(repl_repl, false, sizeof(repl_repl));
if (newOptions != (Datum) 0)
repl_val[Anum_pg_attribute_attoptions - 1] = newOptions;
else
repl_null[Anum_pg_attribute_attoptions - 1] = true;
repl_repl[Anum_pg_attribute_attoptions - 1] = true;
newtuple = heap_modify_tuple(tuple, RelationGetDescr(attrelation),
repl_val, repl_null, repl_repl);
/* Update system catalog. */
simple_heap_update(attrelation, &newtuple->t_self, newtuple);
CatalogUpdateIndexes(attrelation, newtuple);
InvokeObjectPostAlterHook(RelationRelationId,
RelationGetRelid(rel),
attrtuple->attnum);
heap_freetuple(newtuple);
ReleaseSysCache(tuple);
heap_close(attrelation, RowExclusiveLock);
}
/*
* ALTER TABLE ALTER COLUMN SET STORAGE
*/
static void
ATExecSetStorage(Relation rel, const char *colName, Node *newValue, LOCKMODE lockmode)
{
char *storagemode;
char newstorage;
Relation attrelation;
HeapTuple tuple;
Form_pg_attribute attrtuple;
Assert(IsA(newValue, String));
storagemode = strVal(newValue);
if (pg_strcasecmp(storagemode, "plain") == 0)
newstorage = 'p';
else if (pg_strcasecmp(storagemode, "external") == 0)
newstorage = 'e';
else if (pg_strcasecmp(storagemode, "extended") == 0)
newstorage = 'x';
else if (pg_strcasecmp(storagemode, "main") == 0)
newstorage = 'm';
else
{
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("invalid storage type \"%s\"",
storagemode)));
newstorage = 0; /* keep compiler quiet */
}
attrelation = heap_open(AttributeRelationId, RowExclusiveLock);
tuple = SearchSysCacheCopyAttName(RelationGetRelid(rel), colName);
if (!HeapTupleIsValid(tuple))
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_COLUMN),
2004-08-29 07:07:03 +02:00
errmsg("column \"%s\" of relation \"%s\" does not exist",
colName, RelationGetRelationName(rel))));
attrtuple = (Form_pg_attribute) GETSTRUCT(tuple);
if (attrtuple->attnum <= 0)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot alter system column \"%s\"",
colName)));
/*
2005-10-15 04:49:52 +02:00
* safety check: do not allow toasted storage modes unless column datatype
* is TOAST-aware.
*/
if (newstorage == 'p' || TypeIsToastable(attrtuple->atttypid))
attrtuple->attstorage = newstorage;
else
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("column data type %s can only have storage PLAIN",
format_type_be(attrtuple->atttypid))));
simple_heap_update(attrelation, &tuple->t_self, tuple);
/* keep system catalog indexes current */
CatalogUpdateIndexes(attrelation, tuple);
InvokeObjectPostAlterHook(RelationRelationId,
RelationGetRelid(rel),
attrtuple->attnum);
heap_freetuple(tuple);
heap_close(attrelation, RowExclusiveLock);
}
/*
* ALTER TABLE DROP COLUMN
*
* DROP COLUMN cannot use the normal ALTER TABLE recursion mechanism,
* because we have to decide at runtime whether to recurse or not depending
2004-08-29 07:07:03 +02:00
* on whether attinhcount goes to zero or not. (We can't check this in a
* static pre-pass because it won't handle multiple inheritance situations
* correctly.)
*/
static void
ATPrepDropColumn(List **wqueue, Relation rel, bool recurse, bool recursing,
AlterTableCmd *cmd, LOCKMODE lockmode)
{
if (rel->rd_rel->reloftype && !recursing)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("cannot drop column from typed table")));
if (rel->rd_rel->relkind == RELKIND_COMPOSITE_TYPE)
ATTypedTableRecursion(wqueue, rel, cmd, lockmode);
if (recurse)
cmd->subtype = AT_DropColumnRecurse;
}
static void
ATExecDropColumn(List **wqueue, Relation rel, const char *colName,
DropBehavior behavior,
bool recurse, bool recursing,
bool missing_ok, LOCKMODE lockmode)
{
HeapTuple tuple;
Form_pg_attribute targetatt;
AttrNumber attnum;
List *children;
ObjectAddress object;
/* At top level, permission check was done in ATPrepCmd, else do it */
if (recursing)
ATSimplePermissions(rel, ATT_TABLE);
/*
* get the number of the attribute
*/
tuple = SearchSysCacheAttName(RelationGetRelid(rel), colName);
2010-02-26 03:01:40 +01:00
if (!HeapTupleIsValid(tuple))
{
if (!missing_ok)
{
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_COLUMN),
errmsg("column \"%s\" of relation \"%s\" does not exist",
colName, RelationGetRelationName(rel))));
}
else
{
ereport(NOTICE,
(errmsg("column \"%s\" of relation \"%s\" does not exist, skipping",
colName, RelationGetRelationName(rel))));
return;
}
}
targetatt = (Form_pg_attribute) GETSTRUCT(tuple);
attnum = targetatt->attnum;
/* Can't drop a system attribute, except OID */
if (attnum <= 0 && attnum != ObjectIdAttributeNumber)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot drop system column \"%s\"",
colName)));
/* Don't drop inherited columns */
if (targetatt->attinhcount > 0 && !recursing)
ereport(ERROR,
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
errmsg("cannot drop inherited column \"%s\"",
colName)));
ReleaseSysCache(tuple);
/*
* Propagate to children as appropriate. Unlike most other ALTER
2005-10-15 04:49:52 +02:00
* routines, we have to do this one level of recursion at a time; we can't
* use find_all_inheritors to do it in one pass.
*/
children = find_inheritance_children(RelationGetRelid(rel), lockmode);
if (children)
{
Relation attr_rel;
ListCell *child;
attr_rel = heap_open(AttributeRelationId, RowExclusiveLock);
foreach(child, children)
{
Oid childrelid = lfirst_oid(child);
Relation childrel;
Form_pg_attribute childatt;
/* find_inheritance_children already got lock */
childrel = heap_open(childrelid, NoLock);
CheckTableNotInUse(childrel, "ALTER TABLE");
tuple = SearchSysCacheCopyAttName(childrelid, colName);
if (!HeapTupleIsValid(tuple)) /* shouldn't happen */
elog(ERROR, "cache lookup failed for attribute \"%s\" of relation %u",
colName, childrelid);
childatt = (Form_pg_attribute) GETSTRUCT(tuple);
2003-08-04 02:43:34 +02:00
if (childatt->attinhcount <= 0) /* shouldn't happen */
elog(ERROR, "relation %u has non-inherited attribute \"%s\"",
childrelid, colName);
if (recurse)
{
/*
* If the child column has other definition sources, just
2005-10-15 04:49:52 +02:00
* decrement its inheritance count; if not, recurse to delete
* it.
*/
if (childatt->attinhcount == 1 && !childatt->attislocal)
{
/* Time to delete this child column, too */
ATExecDropColumn(wqueue, childrel, colName,
behavior, true, true,
false, lockmode);
}
else
{
/* Child column must survive my deletion */
childatt->attinhcount--;
simple_heap_update(attr_rel, &tuple->t_self, tuple);
/* keep the system catalog indexes current */
CatalogUpdateIndexes(attr_rel, tuple);
/* Make update visible */
CommandCounterIncrement();
}
}
else
{
/*
2005-10-15 04:49:52 +02:00
* If we were told to drop ONLY in this table (no recursion),
* we need to mark the inheritors' attributes as locally
2005-10-15 04:49:52 +02:00
* defined rather than inherited.
*/
childatt->attinhcount--;
childatt->attislocal = true;
simple_heap_update(attr_rel, &tuple->t_self, tuple);
/* keep the system catalog indexes current */
CatalogUpdateIndexes(attr_rel, tuple);
/* Make update visible */
CommandCounterIncrement();
}
heap_freetuple(tuple);
heap_close(childrel, NoLock);
}
heap_close(attr_rel, RowExclusiveLock);
}
/*
* Perform the actual column deletion
*/
object.classId = RelationRelationId;
object.objectId = RelationGetRelid(rel);
object.objectSubId = attnum;
performDeletion(&object, behavior, 0);
/*
* If we dropped the OID column, must adjust pg_class.relhasoids and tell
* Phase 3 to physically get rid of the column. We formerly left the
* column in place physically, but this caused subtle problems. See
* http://archives.postgresql.org/pgsql-hackers/2009-02/msg00363.php
*/
if (attnum == ObjectIdAttributeNumber)
{
Relation class_rel;
Form_pg_class tuple_class;
AlteredTableInfo *tab;
class_rel = heap_open(RelationRelationId, RowExclusiveLock);
tuple = SearchSysCacheCopy1(RELOID,
ObjectIdGetDatum(RelationGetRelid(rel)));
if (!HeapTupleIsValid(tuple))
elog(ERROR, "cache lookup failed for relation %u",
RelationGetRelid(rel));
tuple_class = (Form_pg_class) GETSTRUCT(tuple);
tuple_class->relhasoids = false;
simple_heap_update(class_rel, &tuple->t_self, tuple);
/* Keep the catalog indexes up to date */
CatalogUpdateIndexes(class_rel, tuple);
heap_close(class_rel, RowExclusiveLock);
/* Find or create work queue entry for this table */
tab = ATGetQueueEntry(wqueue, rel);
/* Tell Phase 3 to physically remove the OID column */
tab->rewrite = true;
}
}
/*
* ALTER TABLE ADD INDEX
*
* There is no such command in the grammar, but parse_utilcmd.c converts
* UNIQUE and PRIMARY KEY constraints into AT_AddIndex subcommands. This lets
* us schedule creation of the index at the appropriate time during ALTER.
*/
static void
ATExecAddIndex(AlteredTableInfo *tab, Relation rel,
IndexStmt *stmt, bool is_rebuild, LOCKMODE lockmode)
{
2004-08-29 07:07:03 +02:00
bool check_rights;
bool skip_build;
bool quiet;
Oid new_index;
Assert(IsA(stmt, IndexStmt));
Assert(!stmt->concurrent);
/* suppress schema rights check when rebuilding existing index */
check_rights = !is_rebuild;
/* skip index build if phase 3 will do it or we're reusing an old one */
skip_build = tab->rewrite || OidIsValid(stmt->oldNode);
/* suppress notices when rebuilding existing index */
quiet = is_rebuild;
/* The IndexStmt has already been through transformIndexStmt */
new_index = DefineIndex(stmt,
InvalidOid, /* no predefined OID */
true, /* is_alter_table */
check_rights,
skip_build,
quiet);
/*
* If TryReuseIndex() stashed a relfilenode for us, we used it for the new
* index instead of building from scratch. The DROP of the old edition of
* this index will have scheduled the storage for deletion at commit, so
* cancel that pending deletion.
*/
if (OidIsValid(stmt->oldNode))
{
Relation irel = index_open(new_index, NoLock);
RelationPreserveStorage(irel->rd_node, true);
index_close(irel, NoLock);
}
}
/*
* ALTER TABLE ADD CONSTRAINT USING INDEX
*/
static void
ATExecAddIndexConstraint(AlteredTableInfo *tab, Relation rel,
IndexStmt *stmt, LOCKMODE lockmode)
{
Oid index_oid = stmt->indexOid;
Relation indexRel;
char *indexName;
IndexInfo *indexInfo;
char *constraintName;
char constraintType;
Assert(IsA(stmt, IndexStmt));
Assert(OidIsValid(index_oid));
Assert(stmt->isconstraint);
indexRel = index_open(index_oid, AccessShareLock);
indexName = pstrdup(RelationGetRelationName(indexRel));
indexInfo = BuildIndexInfo(indexRel);
/* this should have been checked at parse time */
if (!indexInfo->ii_Unique)
elog(ERROR, "index \"%s\" is not unique", indexName);
/*
2011-04-10 17:42:00 +02:00
* Determine name to assign to constraint. We require a constraint to
* have the same name as the underlying index; therefore, use the index's
2011-04-10 17:42:00 +02:00
* existing name as the default constraint name, and if the user
* explicitly gives some other name for the constraint, rename the index
* to match.
*/
constraintName = stmt->idxname;
if (constraintName == NULL)
constraintName = indexName;
else if (strcmp(constraintName, indexName) != 0)
{
ereport(NOTICE,
(errmsg("ALTER TABLE / ADD CONSTRAINT USING INDEX will rename index \"%s\" to \"%s\"",
indexName, constraintName)));
RenameRelationInternal(index_oid, constraintName, false);
}
/* Extra checks needed if making primary key */
if (stmt->primary)
index_check_primary_key(rel, indexInfo, true);
/* Note we currently don't support EXCLUSION constraints here */
if (stmt->primary)
constraintType = CONSTRAINT_PRIMARY;
else
constraintType = CONSTRAINT_UNIQUE;
/* Create the catalog entries for the constraint */
index_constraint_create(rel,
index_oid,
indexInfo,
constraintName,
constraintType,
stmt->deferrable,
stmt->initdeferred,
stmt->primary,
true, /* update pg_index */
true, /* remove old dependencies */
allowSystemTableMods,
false); /* is_internal */
index_close(indexRel, NoLock);
}
/*
* ALTER TABLE ADD CONSTRAINT
*/
static void
ATExecAddConstraint(List **wqueue, AlteredTableInfo *tab, Relation rel,
Constraint *newConstraint, bool recurse, bool is_readd,
LOCKMODE lockmode)
{
Assert(IsA(newConstraint, Constraint));
/*
* Currently, we only expect to see CONSTR_CHECK and CONSTR_FOREIGN nodes
* arriving here (see the preprocessing done in parse_utilcmd.c). Use a
* switch anyway to make it easier to add more code later.
*/
switch (newConstraint->contype)
{
case CONSTR_CHECK:
ATAddCheckConstraint(wqueue, tab, rel,
newConstraint, recurse, false, is_readd,
lockmode);
break;
case CONSTR_FOREIGN:
2010-02-26 03:01:40 +01:00
/*
2010-02-26 03:01:40 +01:00
* Note that we currently never recurse for FK constraints, so the
* "recurse" flag is silently ignored.
*
* Assign or validate constraint name
*/
if (newConstraint->conname)
{
if (ConstraintNameIsUsed(CONSTRAINT_RELATION,
RelationGetRelid(rel),
RelationGetNamespace(rel),
newConstraint->conname))
ereport(ERROR,
(errcode(ERRCODE_DUPLICATE_OBJECT),
errmsg("constraint \"%s\" for relation \"%s\" already exists",
newConstraint->conname,
RelationGetRelationName(rel))));
2004-08-29 07:07:03 +02:00
}
else
newConstraint->conname =
ChooseConstraintName(RelationGetRelationName(rel),
2010-02-26 03:01:40 +01:00
strVal(linitial(newConstraint->fk_attrs)),
"fkey",
RelationGetNamespace(rel),
NIL);
ATAddForeignKeyConstraint(tab, rel, newConstraint, lockmode);
break;
default:
elog(ERROR, "unrecognized constraint type: %d",
(int) newConstraint->contype);
}
}
/*
* Add a check constraint to a single table and its children
*
* Subroutine for ATExecAddConstraint.
*
* We must recurse to child tables during execution, rather than using
* ALTER TABLE's normal prep-time recursion. The reason is that all the
* constraints *must* be given the same name, else they won't be seen as
* related later. If the user didn't explicitly specify a name, then
* AddRelationNewConstraints would normally assign different names to the
* child constraints. To fix that, we must capture the name assigned at
* the parent table and pass that down.
*
* When re-adding a previously existing constraint (during ALTER COLUMN TYPE),
* we don't need to recurse here, because recursion will be carried out at a
* higher level; the constraint name issue doesn't apply because the names
* have already been assigned and are just being re-used. We need a separate
* "is_readd" flag for that; just setting recurse=false would result in an
* error if there are child tables.
*/
static void
ATAddCheckConstraint(List **wqueue, AlteredTableInfo *tab, Relation rel,
Constraint *constr, bool recurse, bool recursing,
bool is_readd, LOCKMODE lockmode)
{
List *newcons;
ListCell *lcon;
List *children;
ListCell *child;
/* At top level, permission check was done in ATPrepCmd, else do it */
if (recursing)
ATSimplePermissions(rel, ATT_TABLE);
/*
* Call AddRelationNewConstraints to do the work, making sure it works on
* a copy of the Constraint so transformExpr can't modify the original. It
* returns a list of cooked constraints.
*
* If the constraint ends up getting merged with a pre-existing one, it's
* omitted from the returned list, which is what we want: we do not need
* to do any validation work. That can only happen at child tables,
* though, since we disallow merging at the top level.
*/
newcons = AddRelationNewConstraints(rel, NIL,
list_make1(copyObject(constr)),
recursing, /* allow_merge */
!recursing, /* is_local */
is_readd); /* is_internal */
/* Add each to-be-validated constraint to Phase 3's queue */
foreach(lcon, newcons)
{
CookedConstraint *ccon = (CookedConstraint *) lfirst(lcon);
if (!ccon->skip_validation)
{
NewConstraint *newcon;
newcon = (NewConstraint *) palloc0(sizeof(NewConstraint));
newcon->name = ccon->name;
newcon->contype = ccon->contype;
/* ExecQual wants implicit-AND format */
newcon->qual = (Node *) make_ands_implicit((Expr *) ccon->expr);
tab->constraints = lappend(tab->constraints, newcon);
}
/* Save the actually assigned name if it was defaulted */
if (constr->conname == NULL)
constr->conname = ccon->name;
}
/* At this point we must have a locked-down name to use */
Assert(constr->conname != NULL);
/* Advance command counter in case same table is visited multiple times */
CommandCounterIncrement();
/*
* If the constraint got merged with an existing constraint, we're done.
2011-04-10 17:42:00 +02:00
* We mustn't recurse to child tables in this case, because they've
* already got the constraint, and visiting them again would lead to an
* incorrect value for coninhcount.
*/
if (newcons == NIL)
return;
/*
* If adding a NO INHERIT constraint, no need to find our children.
* Likewise, in a re-add operation, we don't need to recurse (that will be
* handled at higher levels).
*/
if (constr->is_no_inherit || is_readd)
return;
/*
* Propagate to children as appropriate. Unlike most other ALTER
* routines, we have to do this one level of recursion at a time; we can't
* use find_all_inheritors to do it in one pass.
*/
children = find_inheritance_children(RelationGetRelid(rel), lockmode);
/*
* Check if ONLY was specified with ALTER TABLE. If so, allow the
* contraint creation only if there are no children currently. Error out
* otherwise.
*/
if (!recurse && children != NIL)
ereport(ERROR,
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
errmsg("constraint must be added to child tables too")));
foreach(child, children)
{
Oid childrelid = lfirst_oid(child);
Relation childrel;
AlteredTableInfo *childtab;
/* find_inheritance_children already got lock */
childrel = heap_open(childrelid, NoLock);
CheckTableNotInUse(childrel, "ALTER TABLE");
/* Find or create work queue entry for this table */
childtab = ATGetQueueEntry(wqueue, childrel);
/* Recurse to child */
ATAddCheckConstraint(wqueue, childtab, childrel,
constr, recurse, true, is_readd, lockmode);
heap_close(childrel, NoLock);
}
}
/*
* Add a foreign-key constraint to a single table
*
* Subroutine for ATExecAddConstraint. Must already hold exclusive
* lock on the rel, and have done appropriate validity checks for it.
* We do permissions checks here, however.
*/
static void
ATAddForeignKeyConstraint(AlteredTableInfo *tab, Relation rel,
Constraint *fkconstraint, LOCKMODE lockmode)
{
Relation pkrel;
int16 pkattnum[INDEX_MAX_KEYS];
int16 fkattnum[INDEX_MAX_KEYS];
Oid pktypoid[INDEX_MAX_KEYS];
Oid fktypoid[INDEX_MAX_KEYS];
Oid opclasses[INDEX_MAX_KEYS];
Oid pfeqoperators[INDEX_MAX_KEYS];
Oid ppeqoperators[INDEX_MAX_KEYS];
Oid ffeqoperators[INDEX_MAX_KEYS];
int i;
int numfks,
numpks;
Oid indexOid;
Oid constrOid;
bool old_check_ok;
ListCell *old_pfeqop_item = list_head(fkconstraint->old_conpfeqop);
/*
* Grab an exclusive lock on the pk table, so that someone doesn't delete
* rows out from under us. (Although a lesser lock would do for that
* purpose, we'll need exclusive lock anyway to add triggers to the pk
* table; trying to start with a lesser lock will just create a risk of
* deadlock.)
*/
pkrel = heap_openrv(fkconstraint->pktable, AccessExclusiveLock);
/*
* Validity checks (permission checks wait till we have the column
* numbers)
*/
if (pkrel->rd_rel->relkind != RELKIND_RELATION)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("referenced relation \"%s\" is not a table",
RelationGetRelationName(pkrel))));
if (!allowSystemTableMods && IsSystemRelation(pkrel))
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
errmsg("permission denied: \"%s\" is a system catalog",
RelationGetRelationName(pkrel))));
/*
* References from permanent or unlogged tables to temp tables, and from
* permanent tables to unlogged tables, are disallowed because the
* referenced data can vanish out from under us. References from temp
* tables to any other table type are also disallowed, because other
* backends might need to run the RI triggers on the perm table, but they
* can't reliably see tuples in the local buffers of other backends.
*/
switch (rel->rd_rel->relpersistence)
{
case RELPERSISTENCE_PERMANENT:
if (pkrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
ereport(ERROR,
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
errmsg("constraints on permanent tables may reference only permanent tables")));
break;
case RELPERSISTENCE_UNLOGGED:
if (pkrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT
&& pkrel->rd_rel->relpersistence != RELPERSISTENCE_UNLOGGED)
ereport(ERROR,
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
errmsg("constraints on unlogged tables may reference only permanent or unlogged tables")));
break;
case RELPERSISTENCE_TEMP:
if (pkrel->rd_rel->relpersistence != RELPERSISTENCE_TEMP)
ereport(ERROR,
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
errmsg("constraints on temporary tables may reference only temporary tables")));
if (!pkrel->rd_islocaltemp || !rel->rd_islocaltemp)
ereport(ERROR,
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
errmsg("constraints on temporary tables must involve temporary tables of this session")));
break;
}
/*
2005-10-15 04:49:52 +02:00
* Look up the referencing attributes to make sure they exist, and record
* their attnums and type OIDs.
*/
MemSet(pkattnum, 0, sizeof(pkattnum));
MemSet(fkattnum, 0, sizeof(fkattnum));
MemSet(pktypoid, 0, sizeof(pktypoid));
MemSet(fktypoid, 0, sizeof(fktypoid));
MemSet(opclasses, 0, sizeof(opclasses));
MemSet(pfeqoperators, 0, sizeof(pfeqoperators));
MemSet(ppeqoperators, 0, sizeof(ppeqoperators));
MemSet(ffeqoperators, 0, sizeof(ffeqoperators));
numfks = transformColumnNameList(RelationGetRelid(rel),
fkconstraint->fk_attrs,
fkattnum, fktypoid);
/*
2005-10-15 04:49:52 +02:00
* If the attribute list for the referenced table was omitted, lookup the
* definition of the primary key and use it. Otherwise, validate the
* supplied attribute list. In either case, discover the index OID and
* index opclasses, and the attnums and type OIDs of the attributes.
*/
if (fkconstraint->pk_attrs == NIL)
{
numpks = transformFkeyGetPrimaryKey(pkrel, &indexOid,
&fkconstraint->pk_attrs,
pkattnum, pktypoid,
opclasses);
}
else
{
numpks = transformColumnNameList(RelationGetRelid(pkrel),
fkconstraint->pk_attrs,
pkattnum, pktypoid);
/* Look for an index matching the column list */
indexOid = transformFkeyCheckAttrs(pkrel, numpks, pkattnum,
opclasses);
}
/*
* Now we can check permissions.
*/
checkFkeyPermissions(pkrel, pkattnum, numpks);
checkFkeyPermissions(rel, fkattnum, numfks);
/*
* Look up the equality operators to use in the constraint.
*
* Note that we have to be careful about the difference between the actual
* PK column type and the opclass' declared input type, which might be
2007-11-15 22:14:46 +01:00
* only binary-compatible with it. The declared opcintype is the right
* thing to probe pg_amop with.
*/
if (numfks != numpks)
ereport(ERROR,
(errcode(ERRCODE_INVALID_FOREIGN_KEY),
errmsg("number of referencing and referenced columns for foreign key disagree")));
/*
* On the strength of a previous constraint, we might avoid scanning
* tables to validate this one. See below.
*/
old_check_ok = (fkconstraint->old_conpfeqop != NIL);
Assert(!old_check_ok || numfks == list_length(fkconstraint->old_conpfeqop));
for (i = 0; i < numpks; i++)
{
Oid pktype = pktypoid[i];
Oid fktype = fktypoid[i];
Oid fktyped;
HeapTuple cla_ht;
Form_pg_opclass cla_tup;
Oid amid;
Oid opfamily;
Oid opcintype;
Oid pfeqop;
Oid ppeqop;
Oid ffeqop;
int16 eqstrategy;
Oid pfeqop_right;
/* We need several fields out of the pg_opclass entry */
cla_ht = SearchSysCache1(CLAOID, ObjectIdGetDatum(opclasses[i]));
if (!HeapTupleIsValid(cla_ht))
elog(ERROR, "cache lookup failed for opclass %u", opclasses[i]);
cla_tup = (Form_pg_opclass) GETSTRUCT(cla_ht);
amid = cla_tup->opcmethod;
opfamily = cla_tup->opcfamily;
opcintype = cla_tup->opcintype;
ReleaseSysCache(cla_ht);
/*
* Check it's a btree; currently this can never fail since no other
2007-11-15 22:14:46 +01:00
* index AMs support unique indexes. If we ever did have other types
* of unique indexes, we'd need a way to determine which operator
* strategy number is equality. (Is it reasonable to insist that
* every such index AM use btree's number for equality?)
*/
if (amid != BTREE_AM_OID)
elog(ERROR, "only b-tree indexes are supported for foreign keys");
eqstrategy = BTEqualStrategyNumber;
/*
* There had better be a primary equality operator for the index.
* We'll use it for PK = PK comparisons.
*/
ppeqop = get_opfamily_member(opfamily, opcintype, opcintype,
eqstrategy);
if (!OidIsValid(ppeqop))
elog(ERROR, "missing operator %d(%u,%u) in opfamily %u",
eqstrategy, opcintype, opcintype, opfamily);
/*
2007-11-15 22:14:46 +01:00
* Are there equality operators that take exactly the FK type? Assume
* we should look through any domain here.
*/
fktyped = getBaseType(fktype);
pfeqop = get_opfamily_member(opfamily, opcintype, fktyped,
eqstrategy);
if (OidIsValid(pfeqop))
{
pfeqop_right = fktyped;
ffeqop = get_opfamily_member(opfamily, fktyped, fktyped,
eqstrategy);
}
else
{
/* keep compiler quiet */
pfeqop_right = InvalidOid;
ffeqop = InvalidOid;
}
if (!(OidIsValid(pfeqop) && OidIsValid(ffeqop)))
{
/*
2007-11-15 22:14:46 +01:00
* Otherwise, look for an implicit cast from the FK type to the
* opcintype, and if found, use the primary equality operator.
* This is a bit tricky because opcintype might be a polymorphic
* type such as ANYARRAY or ANYENUM; so what we have to test is
* whether the two actual column types can be concurrently cast to
* that type. (Otherwise, we'd fail to reject combinations such
* as int[] and point[].)
*/
2007-11-15 22:14:46 +01:00
Oid input_typeids[2];
Oid target_typeids[2];
input_typeids[0] = pktype;
input_typeids[1] = fktype;
target_typeids[0] = opcintype;
target_typeids[1] = opcintype;
if (can_coerce_type(2, input_typeids, target_typeids,
COERCION_IMPLICIT))
{
pfeqop = ffeqop = ppeqop;
pfeqop_right = opcintype;
}
}
if (!(OidIsValid(pfeqop) && OidIsValid(ffeqop)))
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
errmsg("foreign key constraint \"%s\" "
"cannot be implemented",
fkconstraint->conname),
errdetail("Key columns \"%s\" and \"%s\" "
"are of incompatible types: %s and %s.",
2005-10-15 04:49:52 +02:00
strVal(list_nth(fkconstraint->fk_attrs, i)),
strVal(list_nth(fkconstraint->pk_attrs, i)),
format_type_be(fktype),
format_type_be(pktype))));
if (old_check_ok)
{
/*
* When a pfeqop changes, revalidate the constraint. We could
* permit intra-opfamily changes, but that adds subtle complexity
* without any concrete benefit for core types. We need not
* assess ppeqop or ffeqop, which RI_Initial_Check() does not use.
*/
old_check_ok = (pfeqop == lfirst_oid(old_pfeqop_item));
old_pfeqop_item = lnext(old_pfeqop_item);
}
if (old_check_ok)
{
Oid old_fktype;
Oid new_fktype;
CoercionPathType old_pathtype;
CoercionPathType new_pathtype;
Oid old_castfunc;
Oid new_castfunc;
/*
* Identify coercion pathways from each of the old and new FK-side
* column types to the right (foreign) operand type of the pfeqop.
* We may assume that pg_constraint.conkey is not changing.
*/
old_fktype = tab->oldDesc->attrs[fkattnum[i] - 1]->atttypid;
new_fktype = fktype;
old_pathtype = findFkeyCast(pfeqop_right, old_fktype,
&old_castfunc);
new_pathtype = findFkeyCast(pfeqop_right, new_fktype,
&new_castfunc);
/*
* Upon a change to the cast from the FK column to its pfeqop
* operand, revalidate the constraint. For this evaluation, a
* binary coercion cast is equivalent to no cast at all. While
* type implementors should design implicit casts with an eye
* toward consistency of operations like equality, we cannot
* assume here that they have done so.
*
* A function with a polymorphic argument could change behavior
* arbitrarily in response to get_fn_expr_argtype(). Therefore,
* when the cast destination is polymorphic, we only avoid
* revalidation if the input type has not changed at all. Given
* just the core data types and operator classes, this requirement
* prevents no would-be optimizations.
*
* If the cast converts from a base type to a domain thereon, then
* that domain type must be the opcintype of the unique index.
* Necessarily, the primary key column must then be of the domain
* type. Since the constraint was previously valid, all values on
* the foreign side necessarily exist on the primary side and in
* turn conform to the domain. Consequently, we need not treat
* domains specially here.
*
* Since we require that all collations share the same notion of
* equality (which they do, because texteq reduces to bitwise
* equality), we don't compare collation here.
*
* We need not directly consider the PK type. It's necessarily
* binary coercible to the opcintype of the unique index column,
* and ri_triggers.c will only deal with PK datums in terms of
* that opcintype. Changing the opcintype also changes pfeqop.
*/
old_check_ok = (new_pathtype == old_pathtype &&
new_castfunc == old_castfunc &&
(!IsPolymorphicType(pfeqop_right) ||
new_fktype == old_fktype));
}
pfeqoperators[i] = pfeqop;
ppeqoperators[i] = ppeqop;
ffeqoperators[i] = ffeqop;
}
/*
* Record the FK constraint in pg_constraint.
*/
constrOid = CreateConstraintEntry(fkconstraint->conname,
RelationGetNamespace(rel),
CONSTRAINT_FOREIGN,
fkconstraint->deferrable,
fkconstraint->initdeferred,
fkconstraint->initially_valid,
RelationGetRelid(rel),
fkattnum,
numfks,
2003-08-04 02:43:34 +02:00
InvalidOid, /* not a domain
* constraint */
indexOid,
RelationGetRelid(pkrel),
pkattnum,
pfeqoperators,
ppeqoperators,
ffeqoperators,
numpks,
fkconstraint->fk_upd_action,
fkconstraint->fk_del_action,
fkconstraint->fk_matchtype,
NULL, /* no exclusion constraint */
2003-08-04 02:43:34 +02:00
NULL, /* no check constraint */
NULL,
NULL,
true, /* islocal */
0, /* inhcount */
true, /* isnoinherit */
false); /* is_internal */
/*
* Create the triggers that will enforce the constraint.
*/
createForeignKeyTriggers(rel, fkconstraint, constrOid, indexOid);
/*
* Tell Phase 3 to check that the constraint is satisfied by existing
* rows. We can skip this during table creation, when requested explicitly
* by specifying NOT VALID in an ADD FOREIGN KEY command, and when we're
* recreating a constraint following a SET DATA TYPE operation that did
* not impugn its validity.
*/
if (!old_check_ok && !fkconstraint->skip_validation)
{
NewConstraint *newcon;
newcon = (NewConstraint *) palloc0(sizeof(NewConstraint));
newcon->name = fkconstraint->conname;
newcon->contype = CONSTR_FOREIGN;
newcon->refrelid = RelationGetRelid(pkrel);
newcon->refindid = indexOid;
newcon->conid = constrOid;
newcon->qual = (Node *) fkconstraint;
tab->constraints = lappend(tab->constraints, newcon);
}
/*
* Close pk table, but keep lock until we've committed.
*/
heap_close(pkrel, NoLock);
}
/*
* ALTER TABLE VALIDATE CONSTRAINT
*
* XXX The reason we handle recursion here rather than at Phase 1 is because
* there's no good way to skip recursing when handling foreign keys: there is
* no need to lock children in that case, yet we wouldn't be able to avoid
* doing so at that level.
*/
static void
ATExecValidateConstraint(Relation rel, char *constrName, bool recurse,
bool recursing, LOCKMODE lockmode)
{
Relation conrel;
SysScanDesc scan;
ScanKeyData key;
HeapTuple tuple;
Form_pg_constraint con = NULL;
bool found = false;
conrel = heap_open(ConstraintRelationId, RowExclusiveLock);
/*
* Find and check the target constraint
*/
ScanKeyInit(&key,
Anum_pg_constraint_conrelid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(RelationGetRelid(rel)));
scan = systable_beginscan(conrel, ConstraintRelidIndexId,
true, SnapshotNow, 1, &key);
while (HeapTupleIsValid(tuple = systable_getnext(scan)))
{
con = (Form_pg_constraint) GETSTRUCT(tuple);
if (strcmp(NameStr(con->conname), constrName) == 0)
{
found = true;
break;
}
}
if (!found)
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_OBJECT),
errmsg("constraint \"%s\" of relation \"%s\" does not exist",
constrName, RelationGetRelationName(rel))));
if (con->contype != CONSTRAINT_FOREIGN &&
con->contype != CONSTRAINT_CHECK)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("constraint \"%s\" of relation \"%s\" is not a foreign key or check constraint",
2011-04-10 17:42:00 +02:00
constrName, RelationGetRelationName(rel))));
if (!con->convalidated)
{
HeapTuple copyTuple;
Form_pg_constraint copy_con;
if (con->contype == CONSTRAINT_FOREIGN)
{
Oid conid = HeapTupleGetOid(tuple);
Relation refrel;
/*
* Triggers are already in place on both tables, so a concurrent
* write that alters the result here is not possible. Normally we
* can run a query here to do the validation, which would only
* require AccessShareLock. In some cases, it is possible that we
* might need to fire triggers to perform the check, so we take a
* lock at RowShareLock level just in case.
*/
refrel = heap_open(con->confrelid, RowShareLock);
validateForeignKeyConstraint(constrName, rel, refrel,
con->conindid,
conid);
heap_close(refrel, NoLock);
/*
* Foreign keys do not inherit, so we purposely ignore the
* recursion bit here
*/
}
else if (con->contype == CONSTRAINT_CHECK)
{
List *children = NIL;
ListCell *child;
/*
* If we're recursing, the parent has already done this, so skip
* it.
*/
if (!recursing)
children = find_all_inheritors(RelationGetRelid(rel),
lockmode, NULL);
/*
* For CHECK constraints, we must ensure that we only mark the
* constraint as validated on the parent if it's already validated
* on the children.
*
* We recurse before validating on the parent, to reduce risk of
* deadlocks.
*/
foreach(child, children)
{
Oid childoid = lfirst_oid(child);
Relation childrel;
if (childoid == RelationGetRelid(rel))
continue;
/*
* If we are told not to recurse, there had better not be any
* child tables; else the addition would put them out of step.
*/
if (!recurse)
ereport(ERROR,
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
errmsg("constraint must be validated on child tables too")));
/* find_all_inheritors already got lock */
childrel = heap_open(childoid, NoLock);
ATExecValidateConstraint(childrel, constrName, false,
true, lockmode);
heap_close(childrel, NoLock);
}
validateCheckConstraint(rel, tuple);
/*
* Invalidate relcache so that others see the new validated
* constraint.
*/
CacheInvalidateRelcache(rel);
}
/*
* Now update the catalog, while we have the door open.
*/
copyTuple = heap_copytuple(tuple);
copy_con = (Form_pg_constraint) GETSTRUCT(copyTuple);
copy_con->convalidated = true;
simple_heap_update(conrel, &copyTuple->t_self, copyTuple);
CatalogUpdateIndexes(conrel, copyTuple);
InvokeObjectPostAlterHook(ConstraintRelationId,
HeapTupleGetOid(tuple), 0);
heap_freetuple(copyTuple);
}
systable_endscan(scan);
heap_close(conrel, RowExclusiveLock);
}
/*
* transformColumnNameList - transform list of column names
*
* Lookup each name and return its attnum and type OID
*/
static int
transformColumnNameList(Oid relId, List *colList,
int16 *attnums, Oid *atttypids)
{
ListCell *l;
int attnum;
attnum = 0;
foreach(l, colList)
{
char *attname = strVal(lfirst(l));
HeapTuple atttuple;
atttuple = SearchSysCacheAttName(relId, attname);
if (!HeapTupleIsValid(atttuple))
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_COLUMN),
errmsg("column \"%s\" referenced in foreign key constraint does not exist",
attname)));
if (attnum >= INDEX_MAX_KEYS)
ereport(ERROR,
(errcode(ERRCODE_TOO_MANY_COLUMNS),
2005-10-15 04:49:52 +02:00
errmsg("cannot have more than %d keys in a foreign key",
INDEX_MAX_KEYS)));
attnums[attnum] = ((Form_pg_attribute) GETSTRUCT(atttuple))->attnum;
atttypids[attnum] = ((Form_pg_attribute) GETSTRUCT(atttuple))->atttypid;
ReleaseSysCache(atttuple);
attnum++;
}
return attnum;
}
/*
* transformFkeyGetPrimaryKey -
*
* Look up the names, attnums, and types of the primary key attributes
2004-08-29 07:07:03 +02:00
* for the pkrel. Also return the index OID and index opclasses of the
* index supporting the primary key.
*
2004-08-29 07:07:03 +02:00
* All parameters except pkrel are output parameters. Also, the function
* return value is the number of attributes in the primary key.
*
* Used when the column list in the REFERENCES specification is omitted.
*/
static int
transformFkeyGetPrimaryKey(Relation pkrel, Oid *indexOid,
List **attnamelist,
int16 *attnums, Oid *atttypids,
Oid *opclasses)
{
List *indexoidlist;
ListCell *indexoidscan;
HeapTuple indexTuple = NULL;
Form_pg_index indexStruct = NULL;
Datum indclassDatum;
bool isnull;
oidvector *indclass;
int i;
/*
2005-10-15 04:49:52 +02:00
* Get the list of index OIDs for the table from the relcache, and look up
* each one in the pg_index syscache until we find one marked primary key
Fix assorted bugs in CREATE/DROP INDEX CONCURRENTLY. Commit 8cb53654dbdb4c386369eb988062d0bbb6de725e, which introduced DROP INDEX CONCURRENTLY, managed to break CREATE INDEX CONCURRENTLY via a poor choice of catalog state representation. The pg_index state for an index that's reached the final pre-drop stage was the same as the state for an index just created by CREATE INDEX CONCURRENTLY. This meant that the (necessary) change to make RelationGetIndexList ignore about-to-die indexes also made it ignore freshly-created indexes; which is catastrophic because the latter do need to be considered in HOT-safety decisions. Failure to do so leads to incorrect index entries and subsequently wrong results from queries depending on the concurrently-created index. To fix, add an additional boolean column "indislive" to pg_index, so that the freshly-created and about-to-die states can be distinguished. (This change obviously is only possible in HEAD. This patch will need to be back-patched, but in 9.2 we'll use a kluge consisting of overloading the formerly-impossible state of indisvalid = true and indisready = false.) In addition, change CREATE/DROP INDEX CONCURRENTLY so that the pg_index flag changes they make without exclusive lock on the index are made via heap_inplace_update() rather than a normal transactional update. The latter is not very safe because moving the pg_index tuple could result in concurrent SnapshotNow scans finding it twice or not at all, thus possibly resulting in index corruption. This is a pre-existing bug in CREATE INDEX CONCURRENTLY, which was copied into the DROP code. In addition, fix various places in the code that ought to check to make sure that the indexes they are manipulating are valid and/or ready as appropriate. These represent bugs that have existed since 8.2, since a failed CREATE INDEX CONCURRENTLY could leave a corrupt or invalid index behind, and we ought not try to do anything that might fail with such an index. Also fix RelationReloadIndexInfo to ensure it copies all the pg_index columns that are allowed to change after initial creation. Previously we could have been left with stale values of some fields in an index relcache entry. It's not clear whether this actually had any user-visible consequences, but it's at least a bug waiting to happen. In addition, do some code and docs review for DROP INDEX CONCURRENTLY; some cosmetic code cleanup but mostly addition and revision of comments. This will need to be back-patched, but in a noticeably different form, so I'm committing it to HEAD before working on the back-patch. Problem reported by Amit Kapila, diagnosis by Pavan Deolassee, fix by Tom Lane and Andres Freund.
2012-11-29 03:25:27 +01:00
* (hopefully there isn't more than one such). Insist it's valid, too.
*/
*indexOid = InvalidOid;
indexoidlist = RelationGetIndexList(pkrel);
foreach(indexoidscan, indexoidlist)
{
Oid indexoid = lfirst_oid(indexoidscan);
indexTuple = SearchSysCache1(INDEXRELID, ObjectIdGetDatum(indexoid));
if (!HeapTupleIsValid(indexTuple))
elog(ERROR, "cache lookup failed for index %u", indexoid);
indexStruct = (Form_pg_index) GETSTRUCT(indexTuple);
Fix assorted bugs in CREATE/DROP INDEX CONCURRENTLY. Commit 8cb53654dbdb4c386369eb988062d0bbb6de725e, which introduced DROP INDEX CONCURRENTLY, managed to break CREATE INDEX CONCURRENTLY via a poor choice of catalog state representation. The pg_index state for an index that's reached the final pre-drop stage was the same as the state for an index just created by CREATE INDEX CONCURRENTLY. This meant that the (necessary) change to make RelationGetIndexList ignore about-to-die indexes also made it ignore freshly-created indexes; which is catastrophic because the latter do need to be considered in HOT-safety decisions. Failure to do so leads to incorrect index entries and subsequently wrong results from queries depending on the concurrently-created index. To fix, add an additional boolean column "indislive" to pg_index, so that the freshly-created and about-to-die states can be distinguished. (This change obviously is only possible in HEAD. This patch will need to be back-patched, but in 9.2 we'll use a kluge consisting of overloading the formerly-impossible state of indisvalid = true and indisready = false.) In addition, change CREATE/DROP INDEX CONCURRENTLY so that the pg_index flag changes they make without exclusive lock on the index are made via heap_inplace_update() rather than a normal transactional update. The latter is not very safe because moving the pg_index tuple could result in concurrent SnapshotNow scans finding it twice or not at all, thus possibly resulting in index corruption. This is a pre-existing bug in CREATE INDEX CONCURRENTLY, which was copied into the DROP code. In addition, fix various places in the code that ought to check to make sure that the indexes they are manipulating are valid and/or ready as appropriate. These represent bugs that have existed since 8.2, since a failed CREATE INDEX CONCURRENTLY could leave a corrupt or invalid index behind, and we ought not try to do anything that might fail with such an index. Also fix RelationReloadIndexInfo to ensure it copies all the pg_index columns that are allowed to change after initial creation. Previously we could have been left with stale values of some fields in an index relcache entry. It's not clear whether this actually had any user-visible consequences, but it's at least a bug waiting to happen. In addition, do some code and docs review for DROP INDEX CONCURRENTLY; some cosmetic code cleanup but mostly addition and revision of comments. This will need to be back-patched, but in a noticeably different form, so I'm committing it to HEAD before working on the back-patch. Problem reported by Amit Kapila, diagnosis by Pavan Deolassee, fix by Tom Lane and Andres Freund.
2012-11-29 03:25:27 +01:00
if (indexStruct->indisprimary && IndexIsValid(indexStruct))
{
/*
2010-02-26 03:01:40 +01:00
* Refuse to use a deferrable primary key. This is per SQL spec,
* and there would be a lot of interesting semantic problems if we
* tried to allow it.
*/
if (!indexStruct->indimmediate)
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
errmsg("cannot use a deferrable primary key for referenced table \"%s\"",
RelationGetRelationName(pkrel))));
*indexOid = indexoid;
break;
}
ReleaseSysCache(indexTuple);
}
list_free(indexoidlist);
/*
* Check that we found it
*/
if (!OidIsValid(*indexOid))
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_OBJECT),
2005-10-15 04:49:52 +02:00
errmsg("there is no primary key for referenced table \"%s\"",
RelationGetRelationName(pkrel))));
/* Must get indclass the hard way */
indclassDatum = SysCacheGetAttr(INDEXRELID, indexTuple,
Anum_pg_index_indclass, &isnull);
Assert(!isnull);
indclass = (oidvector *) DatumGetPointer(indclassDatum);
/*
2003-08-04 02:43:34 +02:00
* Now build the list of PK attributes from the indkey definition (we
* assume a primary key cannot have expressional elements)
*/
*attnamelist = NIL;
for (i = 0; i < indexStruct->indnatts; i++)
{
int pkattno = indexStruct->indkey.values[i];
attnums[i] = pkattno;
atttypids[i] = attnumTypeId(pkrel, pkattno);
opclasses[i] = indclass->values[i];
*attnamelist = lappend(*attnamelist,
2005-10-15 04:49:52 +02:00
makeString(pstrdup(NameStr(*attnumAttName(pkrel, pkattno)))));
}
ReleaseSysCache(indexTuple);
return i;
}
/*
* transformFkeyCheckAttrs -
*
* Make sure that the attributes of a referenced table belong to a unique
* (or primary key) constraint. Return the OID of the index supporting
* the constraint, as well as the opclasses associated with the index
* columns.
*/
static Oid
transformFkeyCheckAttrs(Relation pkrel,
int numattrs, int16 *attnums,
2004-08-29 07:07:03 +02:00
Oid *opclasses) /* output parameter */
{
Oid indexoid = InvalidOid;
bool found = false;
bool found_deferrable = false;
List *indexoidlist;
ListCell *indexoidscan;
/*
2005-10-15 04:49:52 +02:00
* Get the list of index OIDs for the table from the relcache, and look up
* each one in the pg_index syscache, and match unique indexes to the list
* of attnums we are given.
*/
indexoidlist = RelationGetIndexList(pkrel);
foreach(indexoidscan, indexoidlist)
{
HeapTuple indexTuple;
Form_pg_index indexStruct;
2003-08-04 02:43:34 +02:00
int i,
j;
indexoid = lfirst_oid(indexoidscan);
indexTuple = SearchSysCache1(INDEXRELID, ObjectIdGetDatum(indexoid));
if (!HeapTupleIsValid(indexTuple))
elog(ERROR, "cache lookup failed for index %u", indexoid);
indexStruct = (Form_pg_index) GETSTRUCT(indexTuple);
/*
* Must have the right number of columns; must be unique and not a
Fix assorted bugs in CREATE/DROP INDEX CONCURRENTLY. Commit 8cb53654dbdb4c386369eb988062d0bbb6de725e, which introduced DROP INDEX CONCURRENTLY, managed to break CREATE INDEX CONCURRENTLY via a poor choice of catalog state representation. The pg_index state for an index that's reached the final pre-drop stage was the same as the state for an index just created by CREATE INDEX CONCURRENTLY. This meant that the (necessary) change to make RelationGetIndexList ignore about-to-die indexes also made it ignore freshly-created indexes; which is catastrophic because the latter do need to be considered in HOT-safety decisions. Failure to do so leads to incorrect index entries and subsequently wrong results from queries depending on the concurrently-created index. To fix, add an additional boolean column "indislive" to pg_index, so that the freshly-created and about-to-die states can be distinguished. (This change obviously is only possible in HEAD. This patch will need to be back-patched, but in 9.2 we'll use a kluge consisting of overloading the formerly-impossible state of indisvalid = true and indisready = false.) In addition, change CREATE/DROP INDEX CONCURRENTLY so that the pg_index flag changes they make without exclusive lock on the index are made via heap_inplace_update() rather than a normal transactional update. The latter is not very safe because moving the pg_index tuple could result in concurrent SnapshotNow scans finding it twice or not at all, thus possibly resulting in index corruption. This is a pre-existing bug in CREATE INDEX CONCURRENTLY, which was copied into the DROP code. In addition, fix various places in the code that ought to check to make sure that the indexes they are manipulating are valid and/or ready as appropriate. These represent bugs that have existed since 8.2, since a failed CREATE INDEX CONCURRENTLY could leave a corrupt or invalid index behind, and we ought not try to do anything that might fail with such an index. Also fix RelationReloadIndexInfo to ensure it copies all the pg_index columns that are allowed to change after initial creation. Previously we could have been left with stale values of some fields in an index relcache entry. It's not clear whether this actually had any user-visible consequences, but it's at least a bug waiting to happen. In addition, do some code and docs review for DROP INDEX CONCURRENTLY; some cosmetic code cleanup but mostly addition and revision of comments. This will need to be back-patched, but in a noticeably different form, so I'm committing it to HEAD before working on the back-patch. Problem reported by Amit Kapila, diagnosis by Pavan Deolassee, fix by Tom Lane and Andres Freund.
2012-11-29 03:25:27 +01:00
* partial index; forget it if there are any expressions, too. Invalid
* indexes are out as well.
*/
if (indexStruct->indnatts == numattrs &&
indexStruct->indisunique &&
Fix assorted bugs in CREATE/DROP INDEX CONCURRENTLY. Commit 8cb53654dbdb4c386369eb988062d0bbb6de725e, which introduced DROP INDEX CONCURRENTLY, managed to break CREATE INDEX CONCURRENTLY via a poor choice of catalog state representation. The pg_index state for an index that's reached the final pre-drop stage was the same as the state for an index just created by CREATE INDEX CONCURRENTLY. This meant that the (necessary) change to make RelationGetIndexList ignore about-to-die indexes also made it ignore freshly-created indexes; which is catastrophic because the latter do need to be considered in HOT-safety decisions. Failure to do so leads to incorrect index entries and subsequently wrong results from queries depending on the concurrently-created index. To fix, add an additional boolean column "indislive" to pg_index, so that the freshly-created and about-to-die states can be distinguished. (This change obviously is only possible in HEAD. This patch will need to be back-patched, but in 9.2 we'll use a kluge consisting of overloading the formerly-impossible state of indisvalid = true and indisready = false.) In addition, change CREATE/DROP INDEX CONCURRENTLY so that the pg_index flag changes they make without exclusive lock on the index are made via heap_inplace_update() rather than a normal transactional update. The latter is not very safe because moving the pg_index tuple could result in concurrent SnapshotNow scans finding it twice or not at all, thus possibly resulting in index corruption. This is a pre-existing bug in CREATE INDEX CONCURRENTLY, which was copied into the DROP code. In addition, fix various places in the code that ought to check to make sure that the indexes they are manipulating are valid and/or ready as appropriate. These represent bugs that have existed since 8.2, since a failed CREATE INDEX CONCURRENTLY could leave a corrupt or invalid index behind, and we ought not try to do anything that might fail with such an index. Also fix RelationReloadIndexInfo to ensure it copies all the pg_index columns that are allowed to change after initial creation. Previously we could have been left with stale values of some fields in an index relcache entry. It's not clear whether this actually had any user-visible consequences, but it's at least a bug waiting to happen. In addition, do some code and docs review for DROP INDEX CONCURRENTLY; some cosmetic code cleanup but mostly addition and revision of comments. This will need to be back-patched, but in a noticeably different form, so I'm committing it to HEAD before working on the back-patch. Problem reported by Amit Kapila, diagnosis by Pavan Deolassee, fix by Tom Lane and Andres Freund.
2012-11-29 03:25:27 +01:00
IndexIsValid(indexStruct) &&
heap_attisnull(indexTuple, Anum_pg_index_indpred) &&
heap_attisnull(indexTuple, Anum_pg_index_indexprs))
{
/* Must get indclass the hard way */
Datum indclassDatum;
bool isnull;
oidvector *indclass;
indclassDatum = SysCacheGetAttr(INDEXRELID, indexTuple,
Anum_pg_index_indclass, &isnull);
Assert(!isnull);
indclass = (oidvector *) DatumGetPointer(indclassDatum);
/*
2005-10-15 04:49:52 +02:00
* The given attnum list may match the index columns in any order.
* Check that each list is a subset of the other.
*/
for (i = 0; i < numattrs; i++)
{
found = false;
for (j = 0; j < numattrs; j++)
{
if (attnums[i] == indexStruct->indkey.values[j])
{
found = true;
break;
}
}
if (!found)
break;
}
if (found)
{
for (i = 0; i < numattrs; i++)
{
found = false;
for (j = 0; j < numattrs; j++)
{
if (attnums[j] == indexStruct->indkey.values[i])
{
opclasses[j] = indclass->values[i];
found = true;
break;
}
}
if (!found)
break;
}
}
/*
2010-02-26 03:01:40 +01:00
* Refuse to use a deferrable unique/primary key. This is per SQL
* spec, and there would be a lot of interesting semantic problems
* if we tried to allow it.
*/
if (found && !indexStruct->indimmediate)
{
/*
2010-02-26 03:01:40 +01:00
* Remember that we found an otherwise matching index, so that
* we can generate a more appropriate error message.
*/
found_deferrable = true;
found = false;
}
}
ReleaseSysCache(indexTuple);
if (found)
break;
}
if (!found)
{
if (found_deferrable)
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
errmsg("cannot use a deferrable unique constraint for referenced table \"%s\"",
RelationGetRelationName(pkrel))));
else
ereport(ERROR,
(errcode(ERRCODE_INVALID_FOREIGN_KEY),
errmsg("there is no unique constraint matching given keys for referenced table \"%s\"",
RelationGetRelationName(pkrel))));
}
list_free(indexoidlist);
return indexoid;
}
/*
* findFkeyCast -
*
* Wrapper around find_coercion_pathway() for ATAddForeignKeyConstraint().
* Caller has equal regard for binary coercibility and for an exact match.
*/
static CoercionPathType
findFkeyCast(Oid targetTypeId, Oid sourceTypeId, Oid *funcid)
{
CoercionPathType ret;
if (targetTypeId == sourceTypeId)
{
ret = COERCION_PATH_RELABELTYPE;
*funcid = InvalidOid;
}
else
{
ret = find_coercion_pathway(targetTypeId, sourceTypeId,
COERCION_IMPLICIT, funcid);
if (ret == COERCION_PATH_NONE)
/* A previously-relied-upon cast is now gone. */
elog(ERROR, "could not find cast from %u to %u",
sourceTypeId, targetTypeId);
}
return ret;
}
/* Permissions checks for ADD FOREIGN KEY */
static void
checkFkeyPermissions(Relation rel, int16 *attnums, int natts)
{
Oid roleid = GetUserId();
AclResult aclresult;
int i;
/* Okay if we have relation-level REFERENCES permission */
aclresult = pg_class_aclcheck(RelationGetRelid(rel), roleid,
ACL_REFERENCES);
if (aclresult == ACLCHECK_OK)
return;
/* Else we must have REFERENCES on each column */
for (i = 0; i < natts; i++)
{
aclresult = pg_attribute_aclcheck(RelationGetRelid(rel), attnums[i],
roleid, ACL_REFERENCES);
if (aclresult != ACLCHECK_OK)
aclcheck_error(aclresult, ACL_KIND_CLASS,
RelationGetRelationName(rel));
}
}
/*
* Scan the existing rows in a table to verify they meet a proposed
* CHECK constraint.
*
* The caller must have opened and locked the relation appropriately.
*/
static void
validateCheckConstraint(Relation rel, HeapTuple constrtup)
{
EState *estate;
Datum val;
char *conbin;
Expr *origexpr;
List *exprstate;
TupleDesc tupdesc;
HeapScanDesc scan;
HeapTuple tuple;
ExprContext *econtext;
MemoryContext oldcxt;
TupleTableSlot *slot;
Form_pg_constraint constrForm;
bool isnull;
constrForm = (Form_pg_constraint) GETSTRUCT(constrtup);
estate = CreateExecutorState();
/*
* XXX this tuple doesn't really come from a syscache, but this doesn't
* matter to SysCacheGetAttr, because it only wants to be able to fetch
* the tupdesc
*/
val = SysCacheGetAttr(CONSTROID, constrtup, Anum_pg_constraint_conbin,
&isnull);
if (isnull)
elog(ERROR, "null conbin for constraint %u",
HeapTupleGetOid(constrtup));
conbin = TextDatumGetCString(val);
origexpr = (Expr *) stringToNode(conbin);
exprstate = (List *)
ExecPrepareExpr((Expr *) make_ands_implicit(origexpr), estate);
econtext = GetPerTupleExprContext(estate);
tupdesc = RelationGetDescr(rel);
slot = MakeSingleTupleTableSlot(tupdesc);
econtext->ecxt_scantuple = slot;
scan = heap_beginscan(rel, SnapshotNow, 0, NULL);
/*
* Switch to per-tuple memory context and reset it for each tuple
* produced, so we don't leak memory.
*/
oldcxt = MemoryContextSwitchTo(GetPerTupleMemoryContext(estate));
while ((tuple = heap_getnext(scan, ForwardScanDirection)) != NULL)
{
ExecStoreTuple(tuple, slot, InvalidBuffer, false);
if (!ExecQual(exprstate, econtext, true))
ereport(ERROR,
(errcode(ERRCODE_CHECK_VIOLATION),
errmsg("check constraint \"%s\" is violated by some row",
NameStr(constrForm->conname)),
errtableconstraint(rel, NameStr(constrForm->conname))));
ResetExprContext(econtext);
}
MemoryContextSwitchTo(oldcxt);
heap_endscan(scan);
ExecDropSingleTupleTableSlot(slot);
FreeExecutorState(estate);
}
/*
* Scan the existing rows in a table to verify they meet a proposed FK
* constraint.
*
* Caller must have opened and locked both relations appropriately.
*/
static void
validateForeignKeyConstraint(char *conname,
Relation rel,
Relation pkrel,
Oid pkindOid,
Oid constraintOid)
{
HeapScanDesc scan;
HeapTuple tuple;
Trigger trig;
ereport(DEBUG1,
(errmsg("validating foreign key constraint \"%s\"", conname)));
/*
* Build a trigger call structure; we'll need it either way.
*/
MemSet(&trig, 0, sizeof(trig));
trig.tgoid = InvalidOid;
trig.tgname = conname;
Changes pg_trigger and extend pg_rewrite in order to allow triggers and rules to be defined with different, per session controllable, behaviors for replication purposes. This will allow replication systems like Slony-I and, as has been stated on pgsql-hackers, other products to control the firing mechanism of triggers and rewrite rules without modifying the system catalog directly. The firing mechanisms are controlled by a new superuser-only GUC variable, session_replication_role, together with a change to pg_trigger.tgenabled and a new column pg_rewrite.ev_enabled. Both columns are a single char data type now (tgenabled was a bool before). The possible values in these attributes are: 'O' - Trigger/Rule fires when session_replication_role is "origin" (default) or "local". This is the default behavior. 'D' - Trigger/Rule is disabled and fires never 'A' - Trigger/Rule fires always regardless of the setting of session_replication_role 'R' - Trigger/Rule fires when session_replication_role is "replica" The GUC variable can only be changed as long as the system does not have any cached query plans. This will prevent changing the session role and accidentally executing stored procedures or functions that have plans cached that expand to the wrong query set due to differences in the rule firing semantics. The SQL syntax for changing a triggers/rules firing semantics is ALTER TABLE <tabname> <when> TRIGGER|RULE <name>; <when> ::= ENABLE | ENABLE ALWAYS | ENABLE REPLICA | DISABLE psql's \d command as well as pg_dump are extended in a backward compatible fashion. Jan
2007-03-20 00:38:32 +01:00
trig.tgenabled = TRIGGER_FIRES_ON_ORIGIN;
trig.tgisinternal = TRUE;
trig.tgconstrrelid = RelationGetRelid(pkrel);
trig.tgconstrindid = pkindOid;
trig.tgconstraint = constraintOid;
trig.tgdeferrable = FALSE;
trig.tginitdeferred = FALSE;
/* we needn't fill in tgargs or tgqual */
/*
* See if we can do it with a single LEFT JOIN query. A FALSE result
* indicates we must proceed with the fire-the-trigger method.
*/
if (RI_Initial_Check(&trig, rel, pkrel))
return;
/*
* Scan through each tuple, calling RI_FKey_check_ins (insert trigger) as
* if that tuple had just been inserted. If any of those fail, it should
* ereport(ERROR) and that's that.
*/
scan = heap_beginscan(rel, SnapshotNow, 0, NULL);
while ((tuple = heap_getnext(scan, ForwardScanDirection)) != NULL)
{
FunctionCallInfoData fcinfo;
TriggerData trigdata;
/*
* Make a call to the trigger function
*
* No parameters are passed, but we do set a context
*/
MemSet(&fcinfo, 0, sizeof(fcinfo));
/*
* We assume RI_FKey_check_ins won't look at flinfo...
*/
trigdata.type = T_TriggerData;
trigdata.tg_event = TRIGGER_EVENT_INSERT | TRIGGER_EVENT_ROW;
trigdata.tg_relation = rel;
trigdata.tg_trigtuple = tuple;
trigdata.tg_newtuple = NULL;
trigdata.tg_trigger = &trig;
trigdata.tg_trigtuplebuf = scan->rs_cbuf;
trigdata.tg_newtuplebuf = InvalidBuffer;
fcinfo.context = (Node *) &trigdata;
RI_FKey_check_ins(&fcinfo);
}
heap_endscan(scan);
}
static void
CreateFKCheckTrigger(RangeVar *myRel, Constraint *fkconstraint,
Oid constraintOid, Oid indexOid, bool on_insert)
{
CreateTrigStmt *fk_trigger;
/*
* Note: for a self-referential FK (referencing and referenced tables are
* the same), it is important that the ON UPDATE action fires before the
* CHECK action, since both triggers will fire on the same row during an
* UPDATE event; otherwise the CHECK trigger will be checking a non-final
* state of the row. Triggers fire in name order, so we ensure this by
* using names like "RI_ConstraintTrigger_a_NNNN" for the action triggers
* and "RI_ConstraintTrigger_c_NNNN" for the check triggers.
*/
fk_trigger = makeNode(CreateTrigStmt);
fk_trigger->trigname = "RI_ConstraintTrigger_c";
fk_trigger->relation = myRel;
fk_trigger->row = true;
fk_trigger->timing = TRIGGER_TYPE_AFTER;
/* Either ON INSERT or ON UPDATE */
if (on_insert)
{
fk_trigger->funcname = SystemFuncName("RI_FKey_check_ins");
fk_trigger->events = TRIGGER_TYPE_INSERT;
}
else
{
fk_trigger->funcname = SystemFuncName("RI_FKey_check_upd");
fk_trigger->events = TRIGGER_TYPE_UPDATE;
}
fk_trigger->columns = NIL;
fk_trigger->whenClause = NULL;
fk_trigger->isconstraint = true;
fk_trigger->deferrable = fkconstraint->deferrable;
fk_trigger->initdeferred = fkconstraint->initdeferred;
fk_trigger->constrrel = fkconstraint->pktable;
fk_trigger->args = NIL;
(void) CreateTrigger(fk_trigger, NULL, constraintOid, indexOid, true);
/* Make changes-so-far visible */
CommandCounterIncrement();
}
/*
* Create the triggers that implement an FK constraint.
*/
static void
createForeignKeyTriggers(Relation rel, Constraint *fkconstraint,
Oid constraintOid, Oid indexOid)
{
RangeVar *myRel;
CreateTrigStmt *fk_trigger;
/*
2005-10-15 04:49:52 +02:00
* Reconstruct a RangeVar for my relation (not passed in, unfortunately).
*/
myRel = makeRangeVar(get_namespace_name(RelationGetNamespace(rel)),
pstrdup(RelationGetRelationName(rel)),
-1);
/* Make changes-so-far visible */
CommandCounterIncrement();
/*
* Build and execute a CREATE CONSTRAINT TRIGGER statement for the ON
* DELETE action on the referenced table.
*/
fk_trigger = makeNode(CreateTrigStmt);
fk_trigger->trigname = "RI_ConstraintTrigger_a";
fk_trigger->relation = fkconstraint->pktable;
fk_trigger->row = true;
fk_trigger->timing = TRIGGER_TYPE_AFTER;
fk_trigger->events = TRIGGER_TYPE_DELETE;
fk_trigger->columns = NIL;
fk_trigger->whenClause = NULL;
fk_trigger->isconstraint = true;
fk_trigger->constrrel = myRel;
switch (fkconstraint->fk_del_action)
{
case FKCONSTR_ACTION_NOACTION:
fk_trigger->deferrable = fkconstraint->deferrable;
fk_trigger->initdeferred = fkconstraint->initdeferred;
fk_trigger->funcname = SystemFuncName("RI_FKey_noaction_del");
break;
case FKCONSTR_ACTION_RESTRICT:
fk_trigger->deferrable = false;
fk_trigger->initdeferred = false;
fk_trigger->funcname = SystemFuncName("RI_FKey_restrict_del");
break;
case FKCONSTR_ACTION_CASCADE:
fk_trigger->deferrable = false;
fk_trigger->initdeferred = false;
fk_trigger->funcname = SystemFuncName("RI_FKey_cascade_del");
break;
case FKCONSTR_ACTION_SETNULL:
fk_trigger->deferrable = false;
fk_trigger->initdeferred = false;
fk_trigger->funcname = SystemFuncName("RI_FKey_setnull_del");
break;
case FKCONSTR_ACTION_SETDEFAULT:
fk_trigger->deferrable = false;
fk_trigger->initdeferred = false;
fk_trigger->funcname = SystemFuncName("RI_FKey_setdefault_del");
break;
default:
elog(ERROR, "unrecognized FK action type: %d",
(int) fkconstraint->fk_del_action);
break;
}
fk_trigger->args = NIL;
(void) CreateTrigger(fk_trigger, NULL, constraintOid, indexOid, true);
/* Make changes-so-far visible */
CommandCounterIncrement();
/*
* Build and execute a CREATE CONSTRAINT TRIGGER statement for the ON
* UPDATE action on the referenced table.
*/
fk_trigger = makeNode(CreateTrigStmt);
fk_trigger->trigname = "RI_ConstraintTrigger_a";
fk_trigger->relation = fkconstraint->pktable;
fk_trigger->row = true;
fk_trigger->timing = TRIGGER_TYPE_AFTER;
fk_trigger->events = TRIGGER_TYPE_UPDATE;
fk_trigger->columns = NIL;
fk_trigger->whenClause = NULL;
fk_trigger->isconstraint = true;
fk_trigger->constrrel = myRel;
switch (fkconstraint->fk_upd_action)
{
case FKCONSTR_ACTION_NOACTION:
fk_trigger->deferrable = fkconstraint->deferrable;
fk_trigger->initdeferred = fkconstraint->initdeferred;
fk_trigger->funcname = SystemFuncName("RI_FKey_noaction_upd");
break;
case FKCONSTR_ACTION_RESTRICT:
fk_trigger->deferrable = false;
fk_trigger->initdeferred = false;
fk_trigger->funcname = SystemFuncName("RI_FKey_restrict_upd");
break;
case FKCONSTR_ACTION_CASCADE:
fk_trigger->deferrable = false;
fk_trigger->initdeferred = false;
fk_trigger->funcname = SystemFuncName("RI_FKey_cascade_upd");
break;
case FKCONSTR_ACTION_SETNULL:
fk_trigger->deferrable = false;
fk_trigger->initdeferred = false;
fk_trigger->funcname = SystemFuncName("RI_FKey_setnull_upd");
break;
case FKCONSTR_ACTION_SETDEFAULT:
fk_trigger->deferrable = false;
fk_trigger->initdeferred = false;
fk_trigger->funcname = SystemFuncName("RI_FKey_setdefault_upd");
break;
default:
elog(ERROR, "unrecognized FK action type: %d",
(int) fkconstraint->fk_upd_action);
break;
}
fk_trigger->args = NIL;
(void) CreateTrigger(fk_trigger, NULL, constraintOid, indexOid, true);
/* Make changes-so-far visible */
CommandCounterIncrement();
/*
* Build and execute CREATE CONSTRAINT TRIGGER statements for the CHECK
* action for both INSERTs and UPDATEs on the referencing table.
*/
CreateFKCheckTrigger(myRel, fkconstraint, constraintOid, indexOid, true);
CreateFKCheckTrigger(myRel, fkconstraint, constraintOid, indexOid, false);
}
/*
* ALTER TABLE DROP CONSTRAINT
*
* Like DROP COLUMN, we can't use the normal ALTER TABLE recursion mechanism.
*/
static void
ATExecDropConstraint(Relation rel, const char *constrName,
DropBehavior behavior,
bool recurse, bool recursing,
bool missing_ok, LOCKMODE lockmode)
{
List *children;
ListCell *child;
Relation conrel;
Form_pg_constraint con;
SysScanDesc scan;
ScanKeyData key;
HeapTuple tuple;
bool found = false;
bool is_no_inherit_constraint = false;
/* At top level, permission check was done in ATPrepCmd, else do it */
if (recursing)
ATSimplePermissions(rel, ATT_TABLE);
conrel = heap_open(ConstraintRelationId, RowExclusiveLock);
/*
* Find and drop the target constraint
*/
ScanKeyInit(&key,
Anum_pg_constraint_conrelid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(RelationGetRelid(rel)));
scan = systable_beginscan(conrel, ConstraintRelidIndexId,
true, SnapshotNow, 1, &key);
while (HeapTupleIsValid(tuple = systable_getnext(scan)))
{
ObjectAddress conobj;
con = (Form_pg_constraint) GETSTRUCT(tuple);
if (strcmp(NameStr(con->conname), constrName) != 0)
continue;
/* Don't drop inherited constraints */
if (con->coninhcount > 0 && !recursing)
ereport(ERROR,
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
errmsg("cannot drop inherited constraint \"%s\" of relation \"%s\"",
constrName, RelationGetRelationName(rel))));
is_no_inherit_constraint = con->connoinherit;
/*
* Perform the actual constraint deletion
*/
conobj.classId = ConstraintRelationId;
conobj.objectId = HeapTupleGetOid(tuple);
conobj.objectSubId = 0;
performDeletion(&conobj, behavior, 0);
found = true;
/* constraint found and dropped -- no need to keep looping */
break;
}
systable_endscan(scan);
2010-02-26 03:01:40 +01:00
if (!found)
{
if (!missing_ok)
{
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_OBJECT),
2010-02-26 03:01:40 +01:00
errmsg("constraint \"%s\" of relation \"%s\" does not exist",
constrName, RelationGetRelationName(rel))));
}
else
{
ereport(NOTICE,
(errmsg("constraint \"%s\" of relation \"%s\" does not exist, skipping",
constrName, RelationGetRelationName(rel))));
heap_close(conrel, RowExclusiveLock);
return;
}
}
2010-02-26 03:01:40 +01:00
/*
* Propagate to children as appropriate. Unlike most other ALTER
* routines, we have to do this one level of recursion at a time; we can't
* use find_all_inheritors to do it in one pass.
*/
if (!is_no_inherit_constraint)
children = find_inheritance_children(RelationGetRelid(rel), lockmode);
else
children = NIL;
foreach(child, children)
{
Oid childrelid = lfirst_oid(child);
Relation childrel;
HeapTuple copy_tuple;
/* find_inheritance_children already got lock */
childrel = heap_open(childrelid, NoLock);
CheckTableNotInUse(childrel, "ALTER TABLE");
ScanKeyInit(&key,
Anum_pg_constraint_conrelid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(childrelid));
scan = systable_beginscan(conrel, ConstraintRelidIndexId,
true, SnapshotNow, 1, &key);
/* scan for matching tuple - there should only be one */
while (HeapTupleIsValid(tuple = systable_getnext(scan)))
{
con = (Form_pg_constraint) GETSTRUCT(tuple);
/* Right now only CHECK constraints can be inherited */
if (con->contype != CONSTRAINT_CHECK)
continue;
if (strcmp(NameStr(con->conname), constrName) == 0)
break;
}
if (!HeapTupleIsValid(tuple))
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_OBJECT),
errmsg("constraint \"%s\" of relation \"%s\" does not exist",
constrName,
RelationGetRelationName(childrel))));
copy_tuple = heap_copytuple(tuple);
systable_endscan(scan);
con = (Form_pg_constraint) GETSTRUCT(copy_tuple);
if (con->coninhcount <= 0) /* shouldn't happen */
elog(ERROR, "relation %u has non-inherited constraint \"%s\"",
childrelid, constrName);
if (recurse)
{
/*
* If the child constraint has other definition sources, just
* decrement its inheritance count; if not, recurse to delete it.
*/
if (con->coninhcount == 1 && !con->conislocal)
{
/* Time to delete this child constraint, too */
ATExecDropConstraint(childrel, constrName, behavior,
true, true,
false, lockmode);
}
else
{
/* Child constraint must survive my deletion */
con->coninhcount--;
simple_heap_update(conrel, &copy_tuple->t_self, copy_tuple);
CatalogUpdateIndexes(conrel, copy_tuple);
/* Make update visible */
CommandCounterIncrement();
}
}
else
{
/*
* If we were told to drop ONLY in this table (no recursion), we
* need to mark the inheritors' constraints as locally defined
* rather than inherited.
*/
con->coninhcount--;
con->conislocal = true;
simple_heap_update(conrel, &copy_tuple->t_self, copy_tuple);
CatalogUpdateIndexes(conrel, copy_tuple);
/* Make update visible */
CommandCounterIncrement();
}
heap_freetuple(copy_tuple);
heap_close(childrel, NoLock);
}
heap_close(conrel, RowExclusiveLock);
}
/*
* ALTER COLUMN TYPE
*/
static void
ATPrepAlterColumnType(List **wqueue,
AlteredTableInfo *tab, Relation rel,
bool recurse, bool recursing,
AlterTableCmd *cmd, LOCKMODE lockmode)
{
char *colName = cmd->name;
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 *def = (ColumnDef *) cmd->def;
TypeName *typeName = def->typeName;
Node *transform = def->raw_default;
HeapTuple tuple;
Form_pg_attribute attTup;
AttrNumber attnum;
Oid targettype;
int32 targettypmod;
Oid targetcollid;
NewColumnValue *newval;
ParseState *pstate = make_parsestate(NULL);
AclResult aclresult;
if (rel->rd_rel->reloftype && !recursing)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("cannot alter column type of typed table")));
/* lookup the attribute so we can check inheritance status */
tuple = SearchSysCacheAttName(RelationGetRelid(rel), colName);
if (!HeapTupleIsValid(tuple))
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_COLUMN),
errmsg("column \"%s\" of relation \"%s\" does not exist",
colName, RelationGetRelationName(rel))));
attTup = (Form_pg_attribute) GETSTRUCT(tuple);
attnum = attTup->attnum;
/* Can't alter a system attribute */
if (attnum <= 0)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot alter system column \"%s\"",
colName)));
/* Don't alter inherited columns */
if (attTup->attinhcount > 0 && !recursing)
ereport(ERROR,
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
errmsg("cannot alter inherited column \"%s\"",
colName)));
/* Look up the target type */
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
typenameTypeIdAndMod(NULL, typeName, &targettype, &targettypmod);
aclresult = pg_type_aclcheck(targettype, GetUserId(), ACL_USAGE);
if (aclresult != ACLCHECK_OK)
aclcheck_error_type(aclresult, targettype);
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
/* And the collation */
targetcollid = GetColumnDefCollation(NULL, def, targettype);
/* make sure datatype is legal for a column */
CheckAttributeType(colName, targettype, targetcollid,
list_make1_oid(rel->rd_rel->reltype),
false);
if (tab->relkind == RELKIND_RELATION)
{
/*
2011-04-10 17:42:00 +02:00
* Set up an expression to transform the old data value to the new
* type. If a USING option was given, transform and use that
* expression, else just take the old value and try to coerce it. We
* do this first so that type incompatibility can be detected before
* we waste effort, and because we need the expression to be parsed
* against the original table row type.
*/
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
if (transform)
{
RangeTblEntry *rte;
/* Expression must be able to access vars of old table */
rte = addRangeTableEntryForRelation(pstate,
rel,
NULL,
false,
true);
addRTEtoQuery(pstate, rte, false, true, true);
transform = transformExpr(pstate, transform,
EXPR_KIND_ALTER_COL_TRANSFORM);
/* It can't return a set */
if (expression_returns_set(transform))
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
2011-04-10 17:42:00 +02:00
errmsg("transform expression must not return a set")));
}
else
{
transform = (Node *) makeVar(1, attnum,
attTup->atttypid, attTup->atttypmod,
attTup->attcollation,
0);
}
transform = coerce_to_target_type(pstate,
transform, exprType(transform),
targettype, targettypmod,
COERCION_ASSIGNMENT,
COERCE_IMPLICIT_CAST,
-1);
if (transform == NULL)
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
errmsg("column \"%s\" cannot be cast automatically to type %s",
colName, format_type_be(targettype)),
errhint("Specify a USING expression to perform the conversion.")));
/* Fix collations after all else */
assign_expr_collations(pstate, transform);
/* Plan the expr now so we can accurately assess the need to rewrite. */
transform = (Node *) expression_planner((Expr *) transform);
/*
* Add a work queue item to make ATRewriteTable update the column
* contents.
*/
newval = (NewColumnValue *) palloc0(sizeof(NewColumnValue));
newval->attnum = attnum;
newval->expr = (Expr *) transform;
tab->newvals = lappend(tab->newvals, newval);
if (ATColumnChangeRequiresRewrite(transform, attnum))
tab->rewrite = 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
else if (transform)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
2011-07-04 23:01:35 +02:00
errmsg("\"%s\" is not a table",
RelationGetRelationName(rel))));
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
if (tab->relkind == RELKIND_COMPOSITE_TYPE ||
tab->relkind == RELKIND_FOREIGN_TABLE)
{
/*
2011-04-10 17:42:00 +02:00
* For composite types, do this check now. Tables will check it later
* when the table is being rewritten.
*/
find_composite_type_dependencies(rel->rd_rel->reltype, rel, NULL);
}
ReleaseSysCache(tuple);
/*
2005-10-15 04:49:52 +02:00
* The recursion case is handled by ATSimpleRecursion. However, if we are
* told not to recurse, there had better not be any child tables; else the
* alter would put them out of step.
*/
if (recurse)
ATSimpleRecursion(wqueue, rel, cmd, recurse, lockmode);
else if (!recursing &&
find_inheritance_children(RelationGetRelid(rel), NoLock) != NIL)
ereport(ERROR,
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
errmsg("type of inherited column \"%s\" must be changed in child tables too",
colName)));
if (tab->relkind == RELKIND_COMPOSITE_TYPE)
ATTypedTableRecursion(wqueue, rel, cmd, lockmode);
}
/*
* When the data type of a column is changed, a rewrite might not be required
* if the new type is sufficiently identical to the old one, and the USING
* clause isn't trying to insert some other value. It's safe to skip the
* rewrite if the old type is binary coercible to the new type, or if the
* new type is an unconstrained domain over the old type. In the case of a
* constrained domain, we could get by with scanning the table and checking
* the constraint rather than actually rewriting it, but we don't currently
* try to do that.
*/
static bool
ATColumnChangeRequiresRewrite(Node *expr, AttrNumber varattno)
{
Assert(expr != NULL);
for (;;)
{
/* only one varno, so no need to check that */
2011-04-10 17:42:00 +02:00
if (IsA(expr, Var) &&((Var *) expr)->varattno == varattno)
return false;
else if (IsA(expr, RelabelType))
expr = (Node *) ((RelabelType *) expr)->arg;
else if (IsA(expr, CoerceToDomain))
{
CoerceToDomain *d = (CoerceToDomain *) expr;
if (GetDomainConstraints(d->resulttype) != NIL)
return true;
expr = (Node *) d->arg;
}
else
return true;
}
}
static void
ATExecAlterColumnType(AlteredTableInfo *tab, Relation rel,
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
AlterTableCmd *cmd, LOCKMODE lockmode)
{
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
char *colName = cmd->name;
ColumnDef *def = (ColumnDef *) cmd->def;
TypeName *typeName = def->typeName;
HeapTuple heapTup;
Form_pg_attribute attTup;
AttrNumber attnum;
HeapTuple typeTuple;
Form_pg_type tform;
Oid targettype;
int32 targettypmod;
Oid targetcollid;
Node *defaultexpr;
Relation attrelation;
Relation depRel;
ScanKeyData key[3];
SysScanDesc scan;
HeapTuple depTup;
attrelation = heap_open(AttributeRelationId, RowExclusiveLock);
/* Look up the target column */
heapTup = SearchSysCacheCopyAttName(RelationGetRelid(rel), colName);
if (!HeapTupleIsValid(heapTup)) /* shouldn't happen */
ereport(ERROR,
2004-08-29 07:07:03 +02:00
(errcode(ERRCODE_UNDEFINED_COLUMN),
errmsg("column \"%s\" of relation \"%s\" does not exist",
colName, RelationGetRelationName(rel))));
attTup = (Form_pg_attribute) GETSTRUCT(heapTup);
attnum = attTup->attnum;
/* Check for multiple ALTER TYPE on same column --- can't cope */
2004-08-29 07:07:03 +02:00
if (attTup->atttypid != tab->oldDesc->attrs[attnum - 1]->atttypid ||
attTup->atttypmod != tab->oldDesc->attrs[attnum - 1]->atttypmod)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot alter type of column \"%s\" twice",
colName)));
/* Look up the target type (should not fail, since prep found it) */
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
typeTuple = typenameType(NULL, typeName, &targettypmod);
tform = (Form_pg_type) GETSTRUCT(typeTuple);
targettype = HeapTupleGetOid(typeTuple);
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
/* And the collation */
targetcollid = GetColumnDefCollation(NULL, def, targettype);
/*
2005-10-15 04:49:52 +02:00
* If there is a default expression for the column, get it and ensure we
* can coerce it to the new datatype. (We must do this before changing
* the column type, because build_column_default itself will try to
* coerce, and will not issue the error message we want if it fails.)
*
* We remove any implicit coercion steps at the top level of the old
* default expression; this has been agreed to satisfy the principle of
* least surprise. (The conversion to the new column type should act like
* it started from what the user sees as the stored expression, and the
2005-10-15 04:49:52 +02:00
* implicit coercions aren't going to be shown.)
*/
if (attTup->atthasdef)
{
defaultexpr = build_column_default(rel, attnum);
Assert(defaultexpr);
defaultexpr = strip_implicit_coercions(defaultexpr);
2004-08-29 07:07:03 +02:00
defaultexpr = coerce_to_target_type(NULL, /* no UNKNOWN params */
2005-10-15 04:49:52 +02:00
defaultexpr, exprType(defaultexpr),
targettype, targettypmod,
COERCION_ASSIGNMENT,
COERCE_IMPLICIT_CAST,
-1);
if (defaultexpr == NULL)
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
errmsg("default for column \"%s\" cannot be cast automatically to type %s",
colName, format_type_be(targettype))));
}
else
defaultexpr = NULL;
/*
2005-10-15 04:49:52 +02:00
* Find everything that depends on the column (constraints, indexes, etc),
* and record enough information to let us recreate the objects.
*
* The actual recreation does not happen here, but only after we have
2005-10-15 04:49:52 +02:00
* performed all the individual ALTER TYPE operations. We have to save
* the info before executing ALTER TYPE, though, else the deparser will
* get confused.
*
* There could be multiple entries for the same object, so we must check
* to ensure we process each one only once. Note: we assume that an index
2005-10-15 04:49:52 +02:00
* that implements a constraint will not show a direct dependency on the
* column.
*/
depRel = heap_open(DependRelationId, RowExclusiveLock);
ScanKeyInit(&key[0],
Anum_pg_depend_refclassid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(RelationRelationId));
ScanKeyInit(&key[1],
Anum_pg_depend_refobjid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(RelationGetRelid(rel)));
ScanKeyInit(&key[2],
Anum_pg_depend_refobjsubid,
BTEqualStrategyNumber, F_INT4EQ,
Int32GetDatum((int32) attnum));
scan = systable_beginscan(depRel, DependReferenceIndexId, true,
SnapshotNow, 3, key);
while (HeapTupleIsValid(depTup = systable_getnext(scan)))
{
2004-08-29 07:07:03 +02:00
Form_pg_depend foundDep = (Form_pg_depend) GETSTRUCT(depTup);
ObjectAddress foundObject;
/* We don't expect any PIN dependencies on columns */
if (foundDep->deptype == DEPENDENCY_PIN)
elog(ERROR, "cannot alter type of a pinned column");
foundObject.classId = foundDep->classid;
foundObject.objectId = foundDep->objid;
foundObject.objectSubId = foundDep->objsubid;
switch (getObjectClass(&foundObject))
{
case OCLASS_CLASS:
{
2004-08-29 07:07:03 +02:00
char relKind = get_rel_relkind(foundObject.objectId);
if (relKind == RELKIND_INDEX)
{
2004-08-29 07:07:03 +02:00
Assert(foundObject.objectSubId == 0);
if (!list_member_oid(tab->changedIndexOids, foundObject.objectId))
{
tab->changedIndexOids = lappend_oid(tab->changedIndexOids,
2005-10-15 04:49:52 +02:00
foundObject.objectId);
2004-08-29 07:07:03 +02:00
tab->changedIndexDefs = lappend(tab->changedIndexDefs,
2005-10-15 04:49:52 +02:00
pg_get_indexdef_string(foundObject.objectId));
2004-08-29 07:07:03 +02:00
}
}
2004-08-29 07:07:03 +02:00
else if (relKind == RELKIND_SEQUENCE)
{
/*
2005-10-15 04:49:52 +02:00
* This must be a SERIAL column's sequence. We need
* not do anything to it.
2004-08-29 07:07:03 +02:00
*/
Assert(foundObject.objectSubId == 0);
}
else
{
/* Not expecting any other direct dependencies... */
elog(ERROR, "unexpected object depending on column: %s",
getObjectDescription(&foundObject));
}
break;
}
case OCLASS_CONSTRAINT:
Assert(foundObject.objectSubId == 0);
if (!list_member_oid(tab->changedConstraintOids,
foundObject.objectId))
{
2006-10-04 02:30:14 +02:00
char *defstring = pg_get_constraintdef_string(foundObject.objectId);
/*
* Put NORMAL dependencies at the front of the list and
* AUTO dependencies at the back. This makes sure that
* foreign-key constraints depending on this column will
* be dropped before unique or primary-key constraints of
* the column; which we must have because the FK
* constraints depend on the indexes belonging to the
* unique constraints.
*/
if (foundDep->deptype == DEPENDENCY_NORMAL)
{
tab->changedConstraintOids =
lcons_oid(foundObject.objectId,
tab->changedConstraintOids);
tab->changedConstraintDefs =
lcons(defstring,
tab->changedConstraintDefs);
}
else
{
tab->changedConstraintOids =
lappend_oid(tab->changedConstraintOids,
foundObject.objectId);
tab->changedConstraintDefs =
lappend(tab->changedConstraintDefs,
defstring);
}
}
break;
case OCLASS_REWRITE:
/* XXX someday see if we can cope with revising views */
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot alter type of a column used by a view or rule"),
errdetail("%s depends on column \"%s\"",
getObjectDescription(&foundObject),
colName)));
break;
case OCLASS_TRIGGER:
2011-04-10 17:42:00 +02:00
/*
* A trigger can depend on a column because the column is
* specified as an update target, or because the column is
* used in the trigger's WHEN condition. The first case would
* not require any extra work, but the second case would
* require updating the WHEN expression, which will take a
2011-04-10 17:42:00 +02:00
* significant amount of new code. Since we can't easily tell
* which case applies, we punt for both. FIXME someday.
*/
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot alter type of a column used in a trigger definition"),
errdetail("%s depends on column \"%s\"",
getObjectDescription(&foundObject),
colName)));
break;
case OCLASS_DEFAULT:
2004-08-29 07:07:03 +02:00
/*
2005-10-15 04:49:52 +02:00
* Ignore the column's default expression, since we will fix
* it below.
*/
Assert(defaultexpr);
break;
case OCLASS_PROC:
case OCLASS_TYPE:
case OCLASS_CAST:
case OCLASS_COLLATION:
case OCLASS_CONVERSION:
case OCLASS_LANGUAGE:
case OCLASS_LARGEOBJECT:
case OCLASS_OPERATOR:
case OCLASS_OPCLASS:
case OCLASS_OPFAMILY:
case OCLASS_AMOP:
case OCLASS_AMPROC:
case OCLASS_SCHEMA:
case OCLASS_TSPARSER:
case OCLASS_TSDICT:
case OCLASS_TSTEMPLATE:
case OCLASS_TSCONFIG:
case OCLASS_ROLE:
case OCLASS_DATABASE:
case OCLASS_TBLSPACE:
case OCLASS_FDW:
case OCLASS_FOREIGN_SERVER:
case OCLASS_USER_MAPPING:
case OCLASS_DEFACL:
case OCLASS_EXTENSION:
2004-08-29 07:07:03 +02:00
/*
2005-10-15 04:49:52 +02:00
* We don't expect any of these sorts of objects to depend on
* a column.
*/
elog(ERROR, "unexpected object depending on column: %s",
getObjectDescription(&foundObject));
break;
default:
elog(ERROR, "unrecognized object class: %u",
foundObject.classId);
}
}
systable_endscan(scan);
/*
* Now scan for dependencies of this column on other things. The only
2005-10-15 04:49:52 +02:00
* thing we should find is the dependency on the column datatype, which we
* want to remove, and possibly a collation dependency.
*/
ScanKeyInit(&key[0],
Anum_pg_depend_classid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(RelationRelationId));
ScanKeyInit(&key[1],
Anum_pg_depend_objid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(RelationGetRelid(rel)));
ScanKeyInit(&key[2],
Anum_pg_depend_objsubid,
BTEqualStrategyNumber, F_INT4EQ,
Int32GetDatum((int32) attnum));
scan = systable_beginscan(depRel, DependDependerIndexId, true,
SnapshotNow, 3, key);
while (HeapTupleIsValid(depTup = systable_getnext(scan)))
{
2004-08-29 07:07:03 +02:00
Form_pg_depend foundDep = (Form_pg_depend) GETSTRUCT(depTup);
if (foundDep->deptype != DEPENDENCY_NORMAL)
elog(ERROR, "found unexpected dependency type '%c'",
foundDep->deptype);
if (!(foundDep->refclassid == TypeRelationId &&
foundDep->refobjid == attTup->atttypid) &&
!(foundDep->refclassid == CollationRelationId &&
foundDep->refobjid == attTup->attcollation))
elog(ERROR, "found unexpected dependency for column");
simple_heap_delete(depRel, &depTup->t_self);
}
systable_endscan(scan);
heap_close(depRel, RowExclusiveLock);
/*
* Here we go --- change the recorded column type and collation. (Note
* heapTup is a copy of the syscache entry, so okay to scribble on.)
*/
attTup->atttypid = targettype;
attTup->atttypmod = targettypmod;
attTup->attcollation = targetcollid;
attTup->attndims = list_length(typeName->arrayBounds);
attTup->attlen = tform->typlen;
attTup->attbyval = tform->typbyval;
attTup->attalign = tform->typalign;
attTup->attstorage = tform->typstorage;
ReleaseSysCache(typeTuple);
simple_heap_update(attrelation, &heapTup->t_self, heapTup);
/* keep system catalog indexes current */
CatalogUpdateIndexes(attrelation, heapTup);
heap_close(attrelation, RowExclusiveLock);
/* Install dependencies on new datatype and collation */
add_column_datatype_dependency(RelationGetRelid(rel), attnum, targettype);
add_column_collation_dependency(RelationGetRelid(rel), attnum, targetcollid);
2004-08-29 07:07:03 +02:00
/*
2005-10-15 04:49:52 +02:00
* Drop any pg_statistic entry for the column, since it's now wrong type
2004-08-29 07:07:03 +02:00
*/
RemoveStatistics(RelationGetRelid(rel), attnum);
InvokeObjectPostAlterHook(RelationRelationId,
RelationGetRelid(rel), attnum);
/*
2005-10-15 04:49:52 +02:00
* Update the default, if present, by brute force --- remove and re-add
* the default. Probably unsafe to take shortcuts, since the new version
* may well have additional dependencies. (It's okay to do this now,
* rather than after other ALTER TYPE commands, since the default won't
* depend on other column types.)
*/
if (defaultexpr)
{
/* Must make new row visible since it will be updated again */
CommandCounterIncrement();
/*
2005-10-15 04:49:52 +02:00
* We use RESTRICT here for safety, but at present we do not expect
* anything to depend on the default.
*/
RemoveAttrDefault(RelationGetRelid(rel), attnum, DROP_RESTRICT, true,
true);
StoreAttrDefault(rel, attnum, defaultexpr, true);
}
/* Cleanup */
heap_freetuple(heapTup);
}
static void
ATExecAlterColumnGenericOptions(Relation rel,
const char *colName,
List *options,
LOCKMODE lockmode)
{
Relation ftrel;
Relation attrel;
ForeignServer *server;
ForeignDataWrapper *fdw;
HeapTuple tuple;
HeapTuple newtuple;
bool isnull;
Datum repl_val[Natts_pg_attribute];
bool repl_null[Natts_pg_attribute];
bool repl_repl[Natts_pg_attribute];
Datum datum;
Form_pg_foreign_table fttableform;
Form_pg_attribute atttableform;
if (options == NIL)
return;
/* First, determine FDW validator associated to the foreign table. */
ftrel = heap_open(ForeignTableRelationId, AccessShareLock);
tuple = SearchSysCache1(FOREIGNTABLEREL, rel->rd_id);
if (!HeapTupleIsValid(tuple))
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_OBJECT),
errmsg("foreign table \"%s\" does not exist",
RelationGetRelationName(rel))));
fttableform = (Form_pg_foreign_table) GETSTRUCT(tuple);
server = GetForeignServer(fttableform->ftserver);
fdw = GetForeignDataWrapper(server->fdwid);
heap_close(ftrel, AccessShareLock);
ReleaseSysCache(tuple);
attrel = heap_open(AttributeRelationId, RowExclusiveLock);
tuple = SearchSysCacheAttName(RelationGetRelid(rel), colName);
if (!HeapTupleIsValid(tuple))
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_COLUMN),
errmsg("column \"%s\" of relation \"%s\" does not exist",
colName, RelationGetRelationName(rel))));
/* Prevent them from altering a system attribute */
atttableform = (Form_pg_attribute) GETSTRUCT(tuple);
if (atttableform->attnum <= 0)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot alter system column \"%s\"", colName)));
/* Initialize buffers for new tuple values */
memset(repl_val, 0, sizeof(repl_val));
memset(repl_null, false, sizeof(repl_null));
memset(repl_repl, false, sizeof(repl_repl));
/* Extract the current options */
datum = SysCacheGetAttr(ATTNAME,
tuple,
Anum_pg_attribute_attfdwoptions,
&isnull);
if (isnull)
datum = PointerGetDatum(NULL);
/* Transform the options */
datum = transformGenericOptions(AttributeRelationId,
datum,
options,
fdw->fdwvalidator);
if (PointerIsValid(DatumGetPointer(datum)))
repl_val[Anum_pg_attribute_attfdwoptions - 1] = datum;
else
repl_null[Anum_pg_attribute_attfdwoptions - 1] = true;
repl_repl[Anum_pg_attribute_attfdwoptions - 1] = true;
/* Everything looks good - update the tuple */
newtuple = heap_modify_tuple(tuple, RelationGetDescr(attrel),
repl_val, repl_null, repl_repl);
simple_heap_update(attrel, &newtuple->t_self, newtuple);
CatalogUpdateIndexes(attrel, newtuple);
InvokeObjectPostAlterHook(RelationRelationId,
RelationGetRelid(rel),
atttableform->attnum);
ReleaseSysCache(tuple);
heap_close(attrel, RowExclusiveLock);
heap_freetuple(newtuple);
}
/*
* Cleanup after we've finished all the ALTER TYPE operations for a
* particular relation. We have to drop and recreate all the indexes
* and constraints that depend on the altered columns.
*/
static void
ATPostAlterTypeCleanup(List **wqueue, AlteredTableInfo *tab, LOCKMODE lockmode)
{
ObjectAddress obj;
ListCell *def_item;
ListCell *oid_item;
/*
2005-10-15 04:49:52 +02:00
* Re-parse the index and constraint definitions, and attach them to the
* appropriate work queue entries. We do this before dropping because in
* the case of a FOREIGN KEY constraint, we might not yet have exclusive
* lock on the table the constraint is attached to, and we need to get
* that before dropping. It's safe because the parser won't actually look
* at the catalogs to detect the existing entry.
*/
forboth(oid_item, tab->changedConstraintOids,
def_item, tab->changedConstraintDefs)
ATPostAlterTypeParse(lfirst_oid(oid_item), (char *) lfirst(def_item),
wqueue, lockmode, tab->rewrite);
forboth(oid_item, tab->changedIndexOids,
def_item, tab->changedIndexDefs)
ATPostAlterTypeParse(lfirst_oid(oid_item), (char *) lfirst(def_item),
wqueue, lockmode, tab->rewrite);
/*
2005-10-15 04:49:52 +02:00
* Now we can drop the existing constraints and indexes --- constraints
* first, since some of them might depend on the indexes. In fact, we
2006-10-04 02:30:14 +02:00
* have to delete FOREIGN KEY constraints before UNIQUE constraints, but
* we already ordered the constraint list to ensure that would happen. It
* should be okay to use DROP_RESTRICT here, since nothing else should be
* depending on these objects.
*/
foreach(oid_item, tab->changedConstraintOids)
{
obj.classId = ConstraintRelationId;
obj.objectId = lfirst_oid(oid_item);
obj.objectSubId = 0;
performDeletion(&obj, DROP_RESTRICT, PERFORM_DELETION_INTERNAL);
}
foreach(oid_item, tab->changedIndexOids)
{
obj.classId = RelationRelationId;
obj.objectId = lfirst_oid(oid_item);
obj.objectSubId = 0;
performDeletion(&obj, DROP_RESTRICT, PERFORM_DELETION_INTERNAL);
}
/*
2005-10-15 04:49:52 +02:00
* The objects will get recreated during subsequent passes over the work
* queue.
*/
}
static void
ATPostAlterTypeParse(Oid oldId, char *cmd,
List **wqueue, LOCKMODE lockmode, bool rewrite)
{
List *raw_parsetree_list;
List *querytree_list;
ListCell *list_item;
/*
2007-11-15 22:14:46 +01:00
* We expect that we will get only ALTER TABLE and CREATE INDEX
* statements. Hence, there is no need to pass them through
* parse_analyze() or the rewriter, but instead we need to pass them
* through parse_utilcmd.c to make them ready for execution.
*/
raw_parsetree_list = raw_parser(cmd);
querytree_list = NIL;
foreach(list_item, raw_parsetree_list)
{
Node *stmt = (Node *) lfirst(list_item);
if (IsA(stmt, IndexStmt))
querytree_list = lappend(querytree_list,
transformIndexStmt((IndexStmt *) stmt,
cmd));
else if (IsA(stmt, AlterTableStmt))
querytree_list = list_concat(querytree_list,
2007-11-15 22:14:46 +01:00
transformAlterTableStmt((AlterTableStmt *) stmt,
cmd));
else
querytree_list = lappend(querytree_list, stmt);
}
/*
2005-10-15 04:49:52 +02:00
* Attach each generated command to the proper place in the work queue.
* Note this could result in creation of entirely new work-queue entries.
*
* Also note that we have to tweak the command subtypes, because it turns
* out that re-creation of indexes and constraints has to act a bit
* differently from initial creation.
*/
foreach(list_item, querytree_list)
{
Node *stm = (Node *) lfirst(list_item);
Relation rel;
AlteredTableInfo *tab;
switch (nodeTag(stm))
{
case T_IndexStmt:
2004-08-29 07:07:03 +02:00
{
IndexStmt *stmt = (IndexStmt *) stm;
2004-08-29 07:07:03 +02:00
AlterTableCmd *newcmd;
if (!rewrite)
TryReuseIndex(oldId, stmt);
rel = relation_openrv(stmt->relation, lockmode);
2004-08-29 07:07:03 +02:00
tab = ATGetQueueEntry(wqueue, rel);
newcmd = makeNode(AlterTableCmd);
newcmd->subtype = AT_ReAddIndex;
newcmd->def = (Node *) stmt;
tab->subcmds[AT_PASS_OLD_INDEX] =
lappend(tab->subcmds[AT_PASS_OLD_INDEX], newcmd);
relation_close(rel, NoLock);
break;
}
case T_AlterTableStmt:
{
AlterTableStmt *stmt = (AlterTableStmt *) stm;
2004-08-29 07:07:03 +02:00
ListCell *lcmd;
rel = relation_openrv(stmt->relation, lockmode);
2004-08-29 07:07:03 +02:00
tab = ATGetQueueEntry(wqueue, rel);
foreach(lcmd, stmt->cmds)
{
2004-08-29 07:07:03 +02:00
AlterTableCmd *cmd = (AlterTableCmd *) lfirst(lcmd);
Constraint *con;
2004-08-29 07:07:03 +02:00
switch (cmd->subtype)
{
case AT_AddIndex:
Assert(IsA(cmd->def, IndexStmt));
if (!rewrite)
TryReuseIndex(get_constraint_index(oldId),
(IndexStmt *) cmd->def);
2004-08-29 07:07:03 +02:00
cmd->subtype = AT_ReAddIndex;
tab->subcmds[AT_PASS_OLD_INDEX] =
lappend(tab->subcmds[AT_PASS_OLD_INDEX], cmd);
break;
case AT_AddConstraint:
Assert(IsA(cmd->def, Constraint));
con = (Constraint *) cmd->def;
/* rewriting neither side of a FK */
if (con->contype == CONSTR_FOREIGN &&
!rewrite && !tab->rewrite)
TryReuseForeignKey(oldId, con);
cmd->subtype = AT_ReAddConstraint;
2004-08-29 07:07:03 +02:00
tab->subcmds[AT_PASS_OLD_CONSTR] =
lappend(tab->subcmds[AT_PASS_OLD_CONSTR], cmd);
break;
default:
elog(ERROR, "unexpected statement type: %d",
(int) cmd->subtype);
}
}
2004-08-29 07:07:03 +02:00
relation_close(rel, NoLock);
break;
}
default:
elog(ERROR, "unexpected statement type: %d",
(int) nodeTag(stm));
}
}
}
/*
* Subroutine for ATPostAlterTypeParse(). Calls out to CheckIndexCompatible()
* for the real analysis, then mutates the IndexStmt based on that verdict.
*/
static void
TryReuseIndex(Oid oldId, IndexStmt *stmt)
{
if (CheckIndexCompatible(oldId,
stmt->relation,
stmt->accessMethod,
stmt->indexParams,
stmt->excludeOpNames))
{
Relation irel = index_open(oldId, NoLock);
stmt->oldNode = irel->rd_node.relNode;
index_close(irel, NoLock);
}
}
/*
* Subroutine for ATPostAlterTypeParse().
*
* Stash the old P-F equality operator into the Constraint node, for possible
* use by ATAddForeignKeyConstraint() in determining whether revalidation of
* this constraint can be skipped.
*/
static void
TryReuseForeignKey(Oid oldId, Constraint *con)
{
HeapTuple tup;
Datum adatum;
bool isNull;
ArrayType *arr;
Oid *rawarr;
int numkeys;
int i;
Assert(con->contype == CONSTR_FOREIGN);
Assert(con->old_conpfeqop == NIL); /* already prepared this node */
tup = SearchSysCache1(CONSTROID, ObjectIdGetDatum(oldId));
if (!HeapTupleIsValid(tup)) /* should not happen */
elog(ERROR, "cache lookup failed for constraint %u", oldId);
adatum = SysCacheGetAttr(CONSTROID, tup,
Anum_pg_constraint_conpfeqop, &isNull);
if (isNull)
elog(ERROR, "null conpfeqop for constraint %u", oldId);
arr = DatumGetArrayTypeP(adatum); /* ensure not toasted */
numkeys = ARR_DIMS(arr)[0];
/* test follows the one in ri_FetchConstraintInfo() */
if (ARR_NDIM(arr) != 1 ||
ARR_HASNULL(arr) ||
ARR_ELEMTYPE(arr) != OIDOID)
elog(ERROR, "conpfeqop is not a 1-D Oid array");
rawarr = (Oid *) ARR_DATA_PTR(arr);
/* stash a List of the operator Oids in our Constraint node */
for (i = 0; i < numkeys; i++)
con->old_conpfeqop = lcons_oid(rawarr[i], con->old_conpfeqop);
ReleaseSysCache(tup);
}
/*
* ALTER TABLE OWNER
*
* recursing is true if we are recursing from a table to its indexes,
* sequences, or toast table. We don't allow the ownership of those things to
* be changed separately from the parent table. Also, we can skip permission
* checks (this is necessary not just an optimization, else we'd fail to
* handle toast tables properly).
*
* recursing is also true if ALTER TYPE OWNER is calling us to fix up a
* free-standing composite type.
*/
void
ATExecChangeOwner(Oid relationOid, Oid newOwnerId, bool recursing, LOCKMODE lockmode)
{
2002-09-04 22:31:48 +02:00
Relation target_rel;
Relation class_rel;
HeapTuple tuple;
Form_pg_class tuple_class;
/*
2005-10-15 04:49:52 +02:00
* Get exclusive lock till end of transaction on the target table. Use
* relation_open so that we can work on indexes and sequences.
*/
target_rel = relation_open(relationOid, lockmode);
/* Get its pg_class tuple, too */
class_rel = heap_open(RelationRelationId, RowExclusiveLock);
tuple = SearchSysCache1(RELOID, ObjectIdGetDatum(relationOid));
if (!HeapTupleIsValid(tuple))
elog(ERROR, "cache lookup failed for relation %u", relationOid);
tuple_class = (Form_pg_class) GETSTRUCT(tuple);
/* Can we change the ownership of this tuple? */
switch (tuple_class->relkind)
{
case RELKIND_RELATION:
case RELKIND_VIEW:
case RELKIND_MATVIEW:
case RELKIND_FOREIGN_TABLE:
/* ok to change owner */
break;
case RELKIND_INDEX:
if (!recursing)
{
/*
* Because ALTER INDEX OWNER used to be allowed, and in fact
* is generated by old versions of pg_dump, we give a warning
* and do nothing rather than erroring out. Also, to avoid
* unnecessary chatter while restoring those old dumps, say
* nothing at all if the command would be a no-op anyway.
*/
if (tuple_class->relowner != newOwnerId)
ereport(WARNING,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("cannot change owner of index \"%s\"",
NameStr(tuple_class->relname)),
errhint("Change the ownership of the index's table, instead.")));
/* quick hack to exit via the no-op path */
newOwnerId = tuple_class->relowner;
}
break;
case RELKIND_SEQUENCE:
if (!recursing &&
tuple_class->relowner != newOwnerId)
{
/* if it's an owned sequence, disallow changing it by itself */
2006-10-04 02:30:14 +02:00
Oid tableId;
int32 colId;
if (sequenceIsOwned(relationOid, &tableId, &colId))
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot change owner of sequence \"%s\"",
NameStr(tuple_class->relname)),
2006-10-04 02:30:14 +02:00
errdetail("Sequence \"%s\" is linked to table \"%s\".",
NameStr(tuple_class->relname),
get_rel_name(tableId))));
}
break;
case RELKIND_COMPOSITE_TYPE:
if (recursing)
break;
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("\"%s\" is a composite type",
NameStr(tuple_class->relname)),
errhint("Use ALTER TYPE instead.")));
break;
case RELKIND_TOASTVALUE:
if (recursing)
break;
/* FALL THRU */
default:
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
2011-06-09 20:32:50 +02:00
errmsg("\"%s\" is not a table, view, sequence, or foreign table",
NameStr(tuple_class->relname))));
}
2004-08-29 07:07:03 +02:00
/*
* If the new owner is the same as the existing owner, consider the
* command to have succeeded. This is for dump restoration purposes.
*/
if (tuple_class->relowner != newOwnerId)
{
Datum repl_val[Natts_pg_class];
bool repl_null[Natts_pg_class];
bool repl_repl[Natts_pg_class];
2004-08-29 07:07:03 +02:00
Acl *newAcl;
Datum aclDatum;
bool isNull;
HeapTuple newtuple;
/* skip permission checks when recursing to index or toast table */
if (!recursing)
{
/* Superusers can always do it */
if (!superuser())
{
2005-10-15 04:49:52 +02:00
Oid namespaceOid = tuple_class->relnamespace;
AclResult aclresult;
/* Otherwise, must be owner of the existing object */
2005-10-15 04:49:52 +02:00
if (!pg_class_ownercheck(relationOid, GetUserId()))
aclcheck_error(ACLCHECK_NOT_OWNER, ACL_KIND_CLASS,
RelationGetRelationName(target_rel));
/* Must be able to become new owner */
check_is_member_of_role(GetUserId(), newOwnerId);
/* New owner must have CREATE privilege on namespace */
aclresult = pg_namespace_aclcheck(namespaceOid, newOwnerId,
ACL_CREATE);
if (aclresult != ACLCHECK_OK)
aclcheck_error(aclresult, ACL_KIND_NAMESPACE,
get_namespace_name(namespaceOid));
}
}
memset(repl_null, false, sizeof(repl_null));
memset(repl_repl, false, sizeof(repl_repl));
repl_repl[Anum_pg_class_relowner - 1] = true;
repl_val[Anum_pg_class_relowner - 1] = ObjectIdGetDatum(newOwnerId);
/*
* Determine the modified ACL for the new owner. This is only
* necessary when the ACL is non-null.
*/
aclDatum = SysCacheGetAttr(RELOID, tuple,
Anum_pg_class_relacl,
&isNull);
if (!isNull)
{
newAcl = aclnewowner(DatumGetAclP(aclDatum),
tuple_class->relowner, newOwnerId);
repl_repl[Anum_pg_class_relacl - 1] = true;
repl_val[Anum_pg_class_relacl - 1] = PointerGetDatum(newAcl);
}
newtuple = heap_modify_tuple(tuple, RelationGetDescr(class_rel), repl_val, repl_null, repl_repl);
simple_heap_update(class_rel, &newtuple->t_self, newtuple);
CatalogUpdateIndexes(class_rel, newtuple);
heap_freetuple(newtuple);
/*
* We must similarly update any per-column ACLs to reflect the new
* owner; for neatness reasons that's split out as a subroutine.
*/
change_owner_fix_column_acls(relationOid,
tuple_class->relowner,
newOwnerId);
/*
* Update owner dependency reference, if any. A composite type has
* none, because it's tracked for the pg_type entry instead of here;
* indexes and TOAST tables don't have their own entries either.
*/
if (tuple_class->relkind != RELKIND_COMPOSITE_TYPE &&
tuple_class->relkind != RELKIND_INDEX &&
tuple_class->relkind != RELKIND_TOASTVALUE)
changeDependencyOnOwner(RelationRelationId, relationOid,
newOwnerId);
/*
* Also change the ownership of the table's row type, if it has one
*/
if (tuple_class->relkind != RELKIND_INDEX)
AlterTypeOwnerInternal(tuple_class->reltype, newOwnerId,
2007-11-15 22:14:46 +01:00
tuple_class->relkind == RELKIND_COMPOSITE_TYPE);
/*
* If we are operating on a table or materialized view, also change
* the ownership of any indexes and sequences that belong to the
* relation, as well as its toast table (if it has one).
*/
if (tuple_class->relkind == RELKIND_RELATION ||
tuple_class->relkind == RELKIND_MATVIEW ||
tuple_class->relkind == RELKIND_TOASTVALUE)
{
List *index_oid_list;
ListCell *i;
/* Find all the indexes belonging to this relation */
index_oid_list = RelationGetIndexList(target_rel);
/* For each index, recursively change its ownership */
foreach(i, index_oid_list)
ATExecChangeOwner(lfirst_oid(i), newOwnerId, true, lockmode);
list_free(index_oid_list);
}
if (tuple_class->relkind == RELKIND_RELATION ||
tuple_class->relkind == RELKIND_MATVIEW)
{
/* If it has a toast table, recurse to change its ownership */
if (tuple_class->reltoastrelid != InvalidOid)
ATExecChangeOwner(tuple_class->reltoastrelid, newOwnerId,
true, lockmode);
/* If it has dependent sequences, recurse to change them too */
change_owner_recurse_to_sequences(relationOid, newOwnerId, lockmode);
}
}
InvokeObjectPostAlterHook(RelationRelationId, relationOid, 0);
ReleaseSysCache(tuple);
heap_close(class_rel, RowExclusiveLock);
relation_close(target_rel, NoLock);
}
/*
* change_owner_fix_column_acls
*
* Helper function for ATExecChangeOwner. Scan the columns of the table
* and fix any non-null column ACLs to reflect the new owner.
*/
static void
change_owner_fix_column_acls(Oid relationOid, Oid oldOwnerId, Oid newOwnerId)
{
Relation attRelation;
SysScanDesc scan;
ScanKeyData key[1];
HeapTuple attributeTuple;
attRelation = heap_open(AttributeRelationId, RowExclusiveLock);
ScanKeyInit(&key[0],
Anum_pg_attribute_attrelid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(relationOid));
scan = systable_beginscan(attRelation, AttributeRelidNumIndexId,
true, SnapshotNow, 1, key);
while (HeapTupleIsValid(attributeTuple = systable_getnext(scan)))
{
Form_pg_attribute att = (Form_pg_attribute) GETSTRUCT(attributeTuple);
Datum repl_val[Natts_pg_attribute];
bool repl_null[Natts_pg_attribute];
bool repl_repl[Natts_pg_attribute];
Acl *newAcl;
Datum aclDatum;
bool isNull;
HeapTuple newtuple;
/* Ignore dropped columns */
if (att->attisdropped)
continue;
aclDatum = heap_getattr(attributeTuple,
Anum_pg_attribute_attacl,
RelationGetDescr(attRelation),
&isNull);
/* Null ACLs do not require changes */
if (isNull)
continue;
memset(repl_null, false, sizeof(repl_null));
memset(repl_repl, false, sizeof(repl_repl));
newAcl = aclnewowner(DatumGetAclP(aclDatum),
oldOwnerId, newOwnerId);
repl_repl[Anum_pg_attribute_attacl - 1] = true;
repl_val[Anum_pg_attribute_attacl - 1] = PointerGetDatum(newAcl);
newtuple = heap_modify_tuple(attributeTuple,
RelationGetDescr(attRelation),
repl_val, repl_null, repl_repl);
simple_heap_update(attRelation, &newtuple->t_self, newtuple);
CatalogUpdateIndexes(attRelation, newtuple);
heap_freetuple(newtuple);
}
systable_endscan(scan);
heap_close(attRelation, RowExclusiveLock);
}
/*
* change_owner_recurse_to_sequences
*
* Helper function for ATExecChangeOwner. Examines pg_depend searching
* for sequences that are dependent on serial columns, and changes their
* ownership.
*/
static void
change_owner_recurse_to_sequences(Oid relationOid, Oid newOwnerId, LOCKMODE lockmode)
{
Relation depRel;
SysScanDesc scan;
2005-10-15 04:49:52 +02:00
ScanKeyData key[2];
HeapTuple tup;
/*
* SERIAL sequences are those having an auto dependency on one of the
2005-10-15 04:49:52 +02:00
* table's columns (we don't care *which* column, exactly).
*/
depRel = heap_open(DependRelationId, AccessShareLock);
ScanKeyInit(&key[0],
2005-10-15 04:49:52 +02:00
Anum_pg_depend_refclassid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(RelationRelationId));
ScanKeyInit(&key[1],
2005-10-15 04:49:52 +02:00
Anum_pg_depend_refobjid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(relationOid));
/* we leave refobjsubid unspecified */
scan = systable_beginscan(depRel, DependReferenceIndexId, true,
SnapshotNow, 2, key);
while (HeapTupleIsValid(tup = systable_getnext(scan)))
{
Form_pg_depend depForm = (Form_pg_depend) GETSTRUCT(tup);
Relation seqRel;
/* skip dependencies other than auto dependencies on columns */
if (depForm->refobjsubid == 0 ||
depForm->classid != RelationRelationId ||
depForm->objsubid != 0 ||
depForm->deptype != DEPENDENCY_AUTO)
continue;
/* Use relation_open just in case it's an index */
seqRel = relation_open(depForm->objid, lockmode);
/* skip non-sequence relations */
if (RelationGetForm(seqRel)->relkind != RELKIND_SEQUENCE)
{
/* No need to keep the lock */
relation_close(seqRel, lockmode);
continue;
}
/* We don't need to close the sequence while we alter it. */
ATExecChangeOwner(depForm->objid, newOwnerId, true, lockmode);
/* Now we can close it. Keep the lock till end of transaction. */
relation_close(seqRel, NoLock);
}
systable_endscan(scan);
relation_close(depRel, AccessShareLock);
}
/*
* ALTER TABLE CLUSTER ON
*
* The only thing we have to do is to change the indisclustered bits.
*/
static void
ATExecClusterOn(Relation rel, const char *indexName, LOCKMODE lockmode)
{
2003-08-04 02:43:34 +02:00
Oid indexOid;
indexOid = get_relname_relid(indexName, rel->rd_rel->relnamespace);
2003-08-04 02:43:34 +02:00
if (!OidIsValid(indexOid))
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_OBJECT),
errmsg("index \"%s\" for table \"%s\" does not exist",
indexName, RelationGetRelationName(rel))));
/* Check index is valid to cluster on */
check_index_is_clusterable(rel, indexOid, false, lockmode);
/* And do the work */
mark_index_clustered(rel, indexOid, false);
}
/*
* ALTER TABLE SET WITHOUT CLUSTER
*
* We have to find any indexes on the table that have indisclustered bit
* set and turn it off.
*/
static void
ATExecDropCluster(Relation rel, LOCKMODE lockmode)
{
mark_index_clustered(rel, InvalidOid, false);
}
/*
* ALTER TABLE SET TABLESPACE
*/
static void
ATPrepSetTableSpace(AlteredTableInfo *tab, Relation rel, char *tablespacename, LOCKMODE lockmode)
{
Oid tablespaceId;
2004-08-29 07:07:03 +02:00
AclResult aclresult;
/* Check that the tablespace exists */
tablespaceId = get_tablespace_oid(tablespacename, false);
/* Check its permissions */
aclresult = pg_tablespace_aclcheck(tablespaceId, GetUserId(), ACL_CREATE);
if (aclresult != ACLCHECK_OK)
aclcheck_error(aclresult, ACL_KIND_TABLESPACE, tablespacename);
/* Save info for Phase 3 to do the real work */
if (OidIsValid(tab->newTableSpace))
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
2005-10-15 04:49:52 +02:00
errmsg("cannot have multiple SET TABLESPACE subcommands")));
tab->newTableSpace = tablespaceId;
}
/*
* Set, reset, or replace reloptions.
*/
static void
ATExecSetRelOptions(Relation rel, List *defList, AlterTableType operation,
LOCKMODE lockmode)
{
Oid relid;
Relation pgclass;
HeapTuple tuple;
HeapTuple newtuple;
Datum datum;
bool isnull;
Datum newOptions;
Datum repl_val[Natts_pg_class];
bool repl_null[Natts_pg_class];
bool repl_repl[Natts_pg_class];
static char *validnsps[] = HEAP_RELOPT_NAMESPACES;
if (defList == NIL && operation != AT_ReplaceRelOptions)
return; /* nothing to do */
pgclass = heap_open(RelationRelationId, RowExclusiveLock);
/* Fetch heap tuple */
relid = RelationGetRelid(rel);
tuple = SearchSysCache1(RELOID, ObjectIdGetDatum(relid));
if (!HeapTupleIsValid(tuple))
elog(ERROR, "cache lookup failed for relation %u", relid);
if (operation == AT_ReplaceRelOptions)
{
/*
* If we're supposed to replace the reloptions list, we just pretend
* there were none before.
*/
datum = (Datum) 0;
isnull = true;
}
else
{
/* Get the old reloptions */
datum = SysCacheGetAttr(RELOID, tuple, Anum_pg_class_reloptions,
&isnull);
}
/* Generate new proposed reloptions (text array) */
newOptions = transformRelOptions(isnull ? (Datum) 0 : datum,
defList, NULL, validnsps, false,
operation == AT_ResetRelOptions);
/* Validate */
switch (rel->rd_rel->relkind)
{
case RELKIND_RELATION:
case RELKIND_TOASTVALUE:
case RELKIND_VIEW:
case RELKIND_MATVIEW:
(void) heap_reloptions(rel->rd_rel->relkind, newOptions, true);
break;
case RELKIND_INDEX:
(void) index_reloptions(rel->rd_am->amoptions, newOptions, true);
break;
default:
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("\"%s\" is not a table, view, materialized view, index, or TOAST table",
RelationGetRelationName(rel))));
break;
}
/*
* All we need do here is update the pg_class row; the new options will be
* propagated into relcaches during post-commit cache inval.
*/
memset(repl_val, 0, sizeof(repl_val));
memset(repl_null, false, sizeof(repl_null));
memset(repl_repl, false, sizeof(repl_repl));
if (newOptions != (Datum) 0)
repl_val[Anum_pg_class_reloptions - 1] = newOptions;
else
repl_null[Anum_pg_class_reloptions - 1] = true;
repl_repl[Anum_pg_class_reloptions - 1] = true;
newtuple = heap_modify_tuple(tuple, RelationGetDescr(pgclass),
repl_val, repl_null, repl_repl);
simple_heap_update(pgclass, &newtuple->t_self, newtuple);
CatalogUpdateIndexes(pgclass, newtuple);
InvokeObjectPostAlterHook(RelationRelationId, RelationGetRelid(rel), 0);
heap_freetuple(newtuple);
ReleaseSysCache(tuple);
/* repeat the whole exercise for the toast table, if there's one */
if (OidIsValid(rel->rd_rel->reltoastrelid))
{
Relation toastrel;
Oid toastid = rel->rd_rel->reltoastrelid;
toastrel = heap_open(toastid, lockmode);
/* Fetch heap tuple */
tuple = SearchSysCache1(RELOID, ObjectIdGetDatum(toastid));
if (!HeapTupleIsValid(tuple))
elog(ERROR, "cache lookup failed for relation %u", toastid);
if (operation == AT_ReplaceRelOptions)
{
/*
* If we're supposed to replace the reloptions list, we just
* pretend there were none before.
*/
datum = (Datum) 0;
isnull = true;
}
else
{
/* Get the old reloptions */
datum = SysCacheGetAttr(RELOID, tuple, Anum_pg_class_reloptions,
&isnull);
}
newOptions = transformRelOptions(isnull ? (Datum) 0 : datum,
defList, "toast", validnsps, false,
operation == AT_ResetRelOptions);
(void) heap_reloptions(RELKIND_TOASTVALUE, newOptions, true);
memset(repl_val, 0, sizeof(repl_val));
memset(repl_null, false, sizeof(repl_null));
memset(repl_repl, false, sizeof(repl_repl));
if (newOptions != (Datum) 0)
repl_val[Anum_pg_class_reloptions - 1] = newOptions;
else
repl_null[Anum_pg_class_reloptions - 1] = true;
repl_repl[Anum_pg_class_reloptions - 1] = true;
newtuple = heap_modify_tuple(tuple, RelationGetDescr(pgclass),
repl_val, repl_null, repl_repl);
simple_heap_update(pgclass, &newtuple->t_self, newtuple);
CatalogUpdateIndexes(pgclass, newtuple);
InvokeObjectPostAlterHookArg(RelationRelationId,
RelationGetRelid(toastrel), 0,
InvalidOid, true);
heap_freetuple(newtuple);
ReleaseSysCache(tuple);
heap_close(toastrel, NoLock);
}
heap_close(pgclass, RowExclusiveLock);
}
/*
* Execute ALTER TABLE SET TABLESPACE for cases where there is no tuple
* rewriting to be done, so we just want to copy the data as fast as possible.
*/
static void
ATExecSetTableSpace(Oid tableOid, Oid newTableSpace, LOCKMODE lockmode)
{
Relation rel;
Oid oldTableSpace;
Oid reltoastrelid;
Oid reltoastidxid;
Oid newrelfilenode;
RelFileNode newrnode;
SMgrRelation dstrel;
Relation pg_class;
HeapTuple tuple;
Form_pg_class rd_rel;
ForkNumber forkNum;
/*
* Need lock here in case we are recursing to toast table or index
*/
rel = relation_open(tableOid, lockmode);
/*
* No work if no change in tablespace.
*/
oldTableSpace = rel->rd_rel->reltablespace;
if (newTableSpace == oldTableSpace ||
(newTableSpace == MyDatabaseTableSpace && oldTableSpace == 0))
{
InvokeObjectPostAlterHook(RelationRelationId,
RelationGetRelid(rel), 0);
relation_close(rel, NoLock);
return;
}
/*
* We cannot support moving mapped relations into different tablespaces.
* (In particular this eliminates all shared catalogs.)
*/
if (RelationIsMapped(rel))
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot move system relation \"%s\"",
RelationGetRelationName(rel))));
/* Can't move a non-shared relation into pg_global */
if (newTableSpace == GLOBALTABLESPACE_OID)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("only shared relations can be placed in pg_global tablespace")));
/*
2005-10-15 04:49:52 +02:00
* Don't allow moving temp tables of other backends ... their local buffer
* manager is not going to cope.
*/
if (RELATION_IS_OTHER_TEMP(rel))
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
2005-10-15 04:49:52 +02:00
errmsg("cannot move temporary tables of other sessions")));
reltoastrelid = rel->rd_rel->reltoastrelid;
reltoastidxid = rel->rd_rel->reltoastidxid;
/* Get a modifiable copy of the relation's pg_class row */
pg_class = heap_open(RelationRelationId, RowExclusiveLock);
tuple = SearchSysCacheCopy1(RELOID, ObjectIdGetDatum(tableOid));
if (!HeapTupleIsValid(tuple))
elog(ERROR, "cache lookup failed for relation %u", tableOid);
rd_rel = (Form_pg_class) GETSTRUCT(tuple);
/*
* Since we copy the file directly without looking at the shared buffers,
* we'd better first flush out any pages of the source relation that are
* in shared buffers. We assume no new changes will be made while we are
* holding exclusive lock on the rel.
*/
FlushRelationBuffers(rel);
/*
* Relfilenodes are not unique across tablespaces, so we need to allocate
* a new one in the new tablespace.
*/
newrelfilenode = GetNewRelFileNode(newTableSpace, NULL,
rel->rd_rel->relpersistence);
/* Open old and new relation */
newrnode = rel->rd_node;
newrnode.relNode = newrelfilenode;
newrnode.spcNode = newTableSpace;
dstrel = smgropen(newrnode, rel->rd_backend);
RelationOpenSmgr(rel);
/*
* Create and copy all forks of the relation, and schedule unlinking of
* old physical files.
*
* NOTE: any conflict in relfilenode value will be caught in
* RelationCreateStorage().
*/
RelationCreateStorage(newrnode, rel->rd_rel->relpersistence);
/* copy main fork */
copy_relation_data(rel->rd_smgr, dstrel, MAIN_FORKNUM,
rel->rd_rel->relpersistence);
/* copy those extra forks that exist */
for (forkNum = MAIN_FORKNUM + 1; forkNum <= MAX_FORKNUM; forkNum++)
{
if (smgrexists(rel->rd_smgr, forkNum))
{
smgrcreate(dstrel, forkNum, false);
copy_relation_data(rel->rd_smgr, dstrel, forkNum,
rel->rd_rel->relpersistence);
}
}
/* drop old relation, and close new one */
RelationDropStorage(rel);
smgrclose(dstrel);
/* update the pg_class row */
rd_rel->reltablespace = (newTableSpace == MyDatabaseTableSpace) ? InvalidOid : newTableSpace;
rd_rel->relfilenode = newrelfilenode;
simple_heap_update(pg_class, &tuple->t_self, tuple);
CatalogUpdateIndexes(pg_class, tuple);
InvokeObjectPostAlterHook(RelationRelationId, RelationGetRelid(rel), 0);
heap_freetuple(tuple);
heap_close(pg_class, RowExclusiveLock);
relation_close(rel, NoLock);
/* Make sure the reltablespace change is visible */
CommandCounterIncrement();
/* Move associated toast relation and/or index, too */
if (OidIsValid(reltoastrelid))
ATExecSetTableSpace(reltoastrelid, newTableSpace, lockmode);
if (OidIsValid(reltoastidxid))
ATExecSetTableSpace(reltoastidxid, newTableSpace, lockmode);
}
/*
* Copy data, block by block
*/
static void
copy_relation_data(SMgrRelation src, SMgrRelation dst,
ForkNumber forkNum, char relpersistence)
{
char *buf;
Page page;
bool use_wal;
BlockNumber nblocks;
BlockNumber blkno;
/*
* palloc the buffer so that it's MAXALIGN'd. If it were just a local
* char[] array, the compiler might align it on any byte boundary, which
* can seriously hurt transfer speed to and from the kernel; not to
* mention possibly making log_newpage's accesses to the page header fail.
*/
buf = (char *) palloc(BLCKSZ);
page = (Page) buf;
/*
* We need to log the copied data in WAL iff WAL archiving/streaming is
* enabled AND it's a permanent relation.
*/
use_wal = XLogIsNeeded() && relpersistence == RELPERSISTENCE_PERMANENT;
nblocks = smgrnblocks(src, forkNum);
for (blkno = 0; blkno < nblocks; blkno++)
{
2010-07-06 21:19:02 +02:00
/* If we got a cancel signal during the copy of the data, quit */
CHECK_FOR_INTERRUPTS();
smgrread(src, forkNum, blkno, buf);
if (!PageIsVerified(page, blkno))
ereport(ERROR,
(errcode(ERRCODE_DATA_CORRUPTED),
errmsg("invalid page in block %u of relation %s",
blkno,
relpathbackend(src->smgr_rnode.node,
src->smgr_rnode.backend,
forkNum))));
/* XLOG stuff */
if (use_wal)
log_newpage(&dst->smgr_rnode.node, forkNum, blkno, page);
PageSetChecksumInplace(page, blkno);
/*
2005-10-15 04:49:52 +02:00
* Now write the page. We say isTemp = true even if it's not a temp
* rel, because there's no need for smgr to schedule an fsync for this
* write; we'll do it ourselves below.
*/
smgrextend(dst, forkNum, blkno, buf, true);
}
pfree(buf);
/*
* If the rel is WAL-logged, must fsync before commit. We use heap_sync
* to ensure that the toast table gets fsync'd too. (For a temp or
* unlogged rel we don't care since the data will be gone after a crash
* anyway.)
*
* It's obvious that we must do this when not WAL-logging the copy. It's
* less obvious that we have to do it even if we did WAL-log the copied
* pages. The reason is that since we're copying outside shared buffers, a
2005-10-15 04:49:52 +02:00
* CHECKPOINT occurring during the copy has no way to flush the previously
* written data to disk (indeed it won't know the new rel even exists). A
* crash later on would replay WAL from the checkpoint, therefore it
* wouldn't replay our earlier WAL entries. If we do not fsync those pages
* here, they might still not be on disk when the crash occurs.
*/
if (relpersistence == RELPERSISTENCE_PERMANENT)
smgrimmedsync(dst, forkNum);
}
/*
* ALTER TABLE ENABLE/DISABLE TRIGGER
*
* We just pass this off to trigger.c.
*/
static void
ATExecEnableDisableTrigger(Relation rel, char *trigname,
2011-04-10 17:42:00 +02:00
char fires_when, bool skip_system, LOCKMODE lockmode)
Changes pg_trigger and extend pg_rewrite in order to allow triggers and rules to be defined with different, per session controllable, behaviors for replication purposes. This will allow replication systems like Slony-I and, as has been stated on pgsql-hackers, other products to control the firing mechanism of triggers and rewrite rules without modifying the system catalog directly. The firing mechanisms are controlled by a new superuser-only GUC variable, session_replication_role, together with a change to pg_trigger.tgenabled and a new column pg_rewrite.ev_enabled. Both columns are a single char data type now (tgenabled was a bool before). The possible values in these attributes are: 'O' - Trigger/Rule fires when session_replication_role is "origin" (default) or "local". This is the default behavior. 'D' - Trigger/Rule is disabled and fires never 'A' - Trigger/Rule fires always regardless of the setting of session_replication_role 'R' - Trigger/Rule fires when session_replication_role is "replica" The GUC variable can only be changed as long as the system does not have any cached query plans. This will prevent changing the session role and accidentally executing stored procedures or functions that have plans cached that expand to the wrong query set due to differences in the rule firing semantics. The SQL syntax for changing a triggers/rules firing semantics is ALTER TABLE <tabname> <when> TRIGGER|RULE <name>; <when> ::= ENABLE | ENABLE ALWAYS | ENABLE REPLICA | DISABLE psql's \d command as well as pg_dump are extended in a backward compatible fashion. Jan
2007-03-20 00:38:32 +01:00
{
EnableDisableTrigger(rel, trigname, fires_when, skip_system);
}
/*
* ALTER TABLE ENABLE/DISABLE RULE
*
* We just pass this off to rewriteDefine.c.
*/
static void
ATExecEnableDisableRule(Relation rel, char *trigname,
char fires_when, LOCKMODE lockmode)
{
Changes pg_trigger and extend pg_rewrite in order to allow triggers and rules to be defined with different, per session controllable, behaviors for replication purposes. This will allow replication systems like Slony-I and, as has been stated on pgsql-hackers, other products to control the firing mechanism of triggers and rewrite rules without modifying the system catalog directly. The firing mechanisms are controlled by a new superuser-only GUC variable, session_replication_role, together with a change to pg_trigger.tgenabled and a new column pg_rewrite.ev_enabled. Both columns are a single char data type now (tgenabled was a bool before). The possible values in these attributes are: 'O' - Trigger/Rule fires when session_replication_role is "origin" (default) or "local". This is the default behavior. 'D' - Trigger/Rule is disabled and fires never 'A' - Trigger/Rule fires always regardless of the setting of session_replication_role 'R' - Trigger/Rule fires when session_replication_role is "replica" The GUC variable can only be changed as long as the system does not have any cached query plans. This will prevent changing the session role and accidentally executing stored procedures or functions that have plans cached that expand to the wrong query set due to differences in the rule firing semantics. The SQL syntax for changing a triggers/rules firing semantics is ALTER TABLE <tabname> <when> TRIGGER|RULE <name>; <when> ::= ENABLE | ENABLE ALWAYS | ENABLE REPLICA | DISABLE psql's \d command as well as pg_dump are extended in a backward compatible fashion. Jan
2007-03-20 00:38:32 +01:00
EnableDisableRule(rel, trigname, fires_when);
}
/*
* ALTER TABLE INHERIT
*
* Add a parent to the child's parents. This verifies that all the columns and
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
* check constraints of the parent appear in the child and that they have the
* same data types and expressions.
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
*/
static void
ATPrepAddInherit(Relation child_rel)
{
if (child_rel->rd_rel->reloftype)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("cannot change inheritance of typed table")));
}
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
static void
ATExecAddInherit(Relation child_rel, RangeVar *parent, LOCKMODE lockmode)
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
{
Relation parent_rel,
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
catalogRelation;
SysScanDesc scan;
ScanKeyData key;
HeapTuple inheritsTuple;
int32 inhseqno;
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
List *children;
/*
* A self-exclusive lock is needed here. See the similar case in
* MergeAttributes() for a full explanation.
*/
parent_rel = heap_openrv(parent, ShareUpdateExclusiveLock);
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
/*
* Must be owner of both parent and child -- child was checked by
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
* ATSimplePermissions call in ATPrepCmd
*/
ATSimplePermissions(parent_rel, ATT_TABLE);
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
/* Permanent rels cannot inherit from temporary ones */
if (parent_rel->rd_rel->relpersistence == RELPERSISTENCE_TEMP &&
child_rel->rd_rel->relpersistence != RELPERSISTENCE_TEMP)
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("cannot inherit from temporary relation \"%s\"",
RelationGetRelationName(parent_rel))));
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
/* If parent rel is temp, it must belong to this session */
if (parent_rel->rd_rel->relpersistence == RELPERSISTENCE_TEMP &&
!parent_rel->rd_islocaltemp)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("cannot inherit from temporary relation of another session")));
/* Ditto for the child */
if (child_rel->rd_rel->relpersistence == RELPERSISTENCE_TEMP &&
!child_rel->rd_islocaltemp)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("cannot inherit to temporary relation of another session")));
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
/*
* Check for duplicates in the list of parents, and determine the highest
* inhseqno already present; we'll use the next one for the new parent.
* (Note: get RowExclusiveLock because we will write pg_inherits below.)
*
* Note: we do not reject the case where the child already inherits from
* the parent indirectly; CREATE TABLE doesn't reject comparable cases.
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
*/
catalogRelation = heap_open(InheritsRelationId, RowExclusiveLock);
ScanKeyInit(&key,
Anum_pg_inherits_inhrelid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(RelationGetRelid(child_rel)));
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
scan = systable_beginscan(catalogRelation, InheritsRelidSeqnoIndexId,
true, SnapshotNow, 1, &key);
/* inhseqno sequences start at 1 */
inhseqno = 0;
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
while (HeapTupleIsValid(inheritsTuple = systable_getnext(scan)))
{
Form_pg_inherits inh = (Form_pg_inherits) GETSTRUCT(inheritsTuple);
if (inh->inhparent == RelationGetRelid(parent_rel))
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
ereport(ERROR,
(errcode(ERRCODE_DUPLICATE_TABLE),
2007-11-15 22:14:46 +01:00
errmsg("relation \"%s\" would be inherited from more than once",
RelationGetRelationName(parent_rel))));
if (inh->inhseqno > inhseqno)
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
inhseqno = inh->inhseqno;
}
systable_endscan(scan);
/*
* Prevent circularity by seeing if proposed parent inherits from child.
* (In particular, this disallows making a rel inherit from itself.)
*
* This is not completely bulletproof because of race conditions: in
2007-11-15 22:14:46 +01:00
* multi-level inheritance trees, someone else could concurrently be
* making another inheritance link that closes the loop but does not join
* either of the rels we have locked. Preventing that seems to require
* exclusive locks on the entire inheritance tree, which is a cure worse
* than the disease. find_all_inheritors() will cope with circularity
* anyway, so don't sweat it too much.
*
* We use weakest lock we can on child's children, namely AccessShareLock.
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
*/
children = find_all_inheritors(RelationGetRelid(child_rel),
AccessShareLock, NULL);
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
if (list_member_oid(children, RelationGetRelid(parent_rel)))
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
ereport(ERROR,
(errcode(ERRCODE_DUPLICATE_TABLE),
errmsg("circular inheritance not allowed"),
errdetail("\"%s\" is already a child of \"%s\".",
parent->relname,
RelationGetRelationName(child_rel))));
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
/* If parent has OIDs then child must have OIDs */
if (parent_rel->rd_rel->relhasoids && !child_rel->rd_rel->relhasoids)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("table \"%s\" without OIDs cannot inherit from table \"%s\" with OIDs",
RelationGetRelationName(child_rel),
RelationGetRelationName(parent_rel))));
/* Match up the columns and bump attinhcount as needed */
MergeAttributesIntoExisting(child_rel, parent_rel);
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
/* Match up the constraints and bump coninhcount as needed */
MergeConstraintsIntoExisting(child_rel, parent_rel);
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
/*
2007-11-15 22:14:46 +01:00
* OK, it looks valid. Make the catalog entries that show inheritance.
*/
StoreCatalogInheritance1(RelationGetRelid(child_rel),
RelationGetRelid(parent_rel),
inhseqno + 1,
catalogRelation);
/* Now we're done with pg_inherits */
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
heap_close(catalogRelation, RowExclusiveLock);
/* keep our lock on the parent relation until commit */
heap_close(parent_rel, NoLock);
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
}
/*
* Obtain the source-text form of the constraint expression for a check
* constraint, given its pg_constraint tuple
*/
static char *
decompile_conbin(HeapTuple contup, TupleDesc tupdesc)
{
Form_pg_constraint con;
bool isnull;
Datum attr;
Datum expr;
con = (Form_pg_constraint) GETSTRUCT(contup);
attr = heap_getattr(contup, Anum_pg_constraint_conbin, tupdesc, &isnull);
if (isnull)
elog(ERROR, "null conbin for constraint %u", HeapTupleGetOid(contup));
expr = DirectFunctionCall2(pg_get_expr, attr,
ObjectIdGetDatum(con->conrelid));
return TextDatumGetCString(expr);
}
/*
* Determine whether two check constraints are functionally equivalent
*
* The test we apply is to see whether they reverse-compile to the same
* source string. This insulates us from issues like whether attributes
* have the same physical column numbers in parent and child relations.
*/
static bool
constraints_equivalent(HeapTuple a, HeapTuple b, TupleDesc tupleDesc)
{
Form_pg_constraint acon = (Form_pg_constraint) GETSTRUCT(a);
Form_pg_constraint bcon = (Form_pg_constraint) GETSTRUCT(b);
if (acon->condeferrable != bcon->condeferrable ||
acon->condeferred != bcon->condeferred ||
strcmp(decompile_conbin(a, tupleDesc),
decompile_conbin(b, tupleDesc)) != 0)
return false;
else
return true;
}
/*
* Check columns in child table match up with columns in parent, and increment
* their attinhcount.
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
*
* Called by ATExecAddInherit
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
*
* Currently all parent columns must be found in child. Missing columns are an
* error. One day we might consider creating new columns like CREATE TABLE
* does. However, that is widely unpopular --- in the common use case of
* partitioned tables it's a foot-gun.
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
*
* The data type must match exactly. If the parent column is NOT NULL then
* the child must be as well. Defaults are not compared, however.
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
*/
static void
MergeAttributesIntoExisting(Relation child_rel, Relation parent_rel)
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
{
Relation attrrel;
2006-10-04 02:30:14 +02:00
AttrNumber parent_attno;
int parent_natts;
TupleDesc tupleDesc;
HeapTuple tuple;
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
attrrel = heap_open(AttributeRelationId, RowExclusiveLock);
tupleDesc = RelationGetDescr(parent_rel);
parent_natts = tupleDesc->natts;
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
for (parent_attno = 1; parent_attno <= parent_natts; parent_attno++)
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
{
Form_pg_attribute attribute = tupleDesc->attrs[parent_attno - 1];
char *attributeName = NameStr(attribute->attname);
/* Ignore dropped columns in the parent. */
if (attribute->attisdropped)
continue;
/* Find same column in child (matching on column name). */
tuple = SearchSysCacheCopyAttName(RelationGetRelid(child_rel),
attributeName);
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
if (HeapTupleIsValid(tuple))
{
/* Check they are same type, typmod, and collation */
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
Form_pg_attribute childatt = (Form_pg_attribute) GETSTRUCT(tuple);
if (attribute->atttypid != childatt->atttypid ||
attribute->atttypmod != childatt->atttypmod)
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
errmsg("child table \"%s\" has different type for column \"%s\"",
RelationGetRelationName(child_rel),
attributeName)));
if (attribute->attcollation != childatt->attcollation)
ereport(ERROR,
(errcode(ERRCODE_COLLATION_MISMATCH),
errmsg("child table \"%s\" has different collation for column \"%s\"",
RelationGetRelationName(child_rel),
attributeName)));
/*
* Check child doesn't discard NOT NULL property. (Other
* constraints are checked elsewhere.)
*/
if (attribute->attnotnull && !childatt->attnotnull)
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
2007-11-15 22:14:46 +01:00
errmsg("column \"%s\" in child table must be marked NOT NULL",
attributeName)));
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
/*
* OK, bump the child column's inheritance count. (If we fail
* later on, this change will just roll back.)
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
*/
childatt->attinhcount++;
simple_heap_update(attrrel, &tuple->t_self, tuple);
CatalogUpdateIndexes(attrrel, tuple);
heap_freetuple(tuple);
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
}
else
{
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
2006-10-06 19:14:01 +02:00
errmsg("child table is missing column \"%s\"",
attributeName)));
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
}
}
heap_close(attrrel, RowExclusiveLock);
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
}
/*
* Check constraints in child table match up with constraints in parent,
* and increment their coninhcount.
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
*
* Constraints that are marked ONLY in the parent are ignored.
*
* Called by ATExecAddInherit
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
*
* Currently all constraints in parent must be present in the child. One day we
* may consider adding new constraints like CREATE TABLE does.
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
*
* XXX This is O(N^2) which may be an issue with tables with hundreds of
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
* constraints. As long as tables have more like 10 constraints it shouldn't be
* a problem though. Even 100 constraints ought not be the end of the world.
*
* XXX See MergeWithExistingConstraint too if you change this code.
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
*/
static void
MergeConstraintsIntoExisting(Relation child_rel, Relation parent_rel)
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
{
Relation catalog_relation;
TupleDesc tuple_desc;
SysScanDesc parent_scan;
ScanKeyData parent_key;
HeapTuple parent_tuple;
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
catalog_relation = heap_open(ConstraintRelationId, RowExclusiveLock);
tuple_desc = RelationGetDescr(catalog_relation);
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
/* Outer loop scans through the parent's constraint definitions */
ScanKeyInit(&parent_key,
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
Anum_pg_constraint_conrelid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(RelationGetRelid(parent_rel)));
parent_scan = systable_beginscan(catalog_relation, ConstraintRelidIndexId,
true, SnapshotNow, 1, &parent_key);
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
while (HeapTupleIsValid(parent_tuple = systable_getnext(parent_scan)))
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
{
Form_pg_constraint parent_con = (Form_pg_constraint) GETSTRUCT(parent_tuple);
SysScanDesc child_scan;
ScanKeyData child_key;
HeapTuple child_tuple;
bool found = false;
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
if (parent_con->contype != CONSTRAINT_CHECK)
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
continue;
/* if the parent's constraint is marked NO INHERIT, it's not inherited */
if (parent_con->connoinherit)
continue;
/* Search for a child constraint matching this one */
ScanKeyInit(&child_key,
Anum_pg_constraint_conrelid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(RelationGetRelid(child_rel)));
child_scan = systable_beginscan(catalog_relation, ConstraintRelidIndexId,
true, SnapshotNow, 1, &child_key);
while (HeapTupleIsValid(child_tuple = systable_getnext(child_scan)))
{
Form_pg_constraint child_con = (Form_pg_constraint) GETSTRUCT(child_tuple);
HeapTuple child_copy;
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
if (child_con->contype != CONSTRAINT_CHECK)
continue;
if (strcmp(NameStr(parent_con->conname),
NameStr(child_con->conname)) != 0)
continue;
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
if (!constraints_equivalent(parent_tuple, child_tuple, tuple_desc))
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
errmsg("child table \"%s\" has different definition for check constraint \"%s\"",
RelationGetRelationName(child_rel),
NameStr(parent_con->conname))));
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
/* If the constraint is "no inherit" then cannot merge */
if (child_con->connoinherit)
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("constraint \"%s\" conflicts with non-inherited constraint on child table \"%s\"",
NameStr(child_con->conname),
RelationGetRelationName(child_rel))));
/*
* OK, bump the child constraint's inheritance count. (If we fail
* later on, this change will just roll back.)
*/
child_copy = heap_copytuple(child_tuple);
child_con = (Form_pg_constraint) GETSTRUCT(child_copy);
child_con->coninhcount++;
simple_heap_update(catalog_relation, &child_copy->t_self, child_copy);
CatalogUpdateIndexes(catalog_relation, child_copy);
heap_freetuple(child_copy);
found = true;
break;
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
}
systable_endscan(child_scan);
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
if (!found)
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
errmsg("child table is missing constraint \"%s\"",
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
NameStr(parent_con->conname))));
}
systable_endscan(parent_scan);
heap_close(catalog_relation, RowExclusiveLock);
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
}
/*
* ALTER TABLE NO INHERIT
*
* Drop a parent from the child's parents. This just adjusts the attinhcount
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
* and attislocal of the columns and removes the pg_inherit and pg_depend
* entries.
*
* If attinhcount goes to 0 then attislocal gets set to true. If it goes back
* up attislocal stays true, which means if a child is ever removed from a
* parent then its columns will never be automatically dropped which may
* surprise. But at least we'll never surprise by dropping columns someone
* isn't expecting to be dropped which would actually mean data loss.
*
* coninhcount and conislocal for inherited constraints are adjusted in
* exactly the same way.
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
*/
static void
ATExecDropInherit(Relation rel, RangeVar *parent, LOCKMODE lockmode)
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
{
Relation parent_rel;
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
Relation catalogRelation;
SysScanDesc scan;
ScanKeyData key[3];
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
HeapTuple inheritsTuple,
attributeTuple,
constraintTuple;
List *connames;
bool found = false;
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
/*
2007-11-15 22:14:46 +01:00
* AccessShareLock on the parent is probably enough, seeing that DROP
* TABLE doesn't lock parent tables at all. We need some lock since we'll
* be inspecting the parent's schema.
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
*/
parent_rel = heap_openrv(parent, AccessShareLock);
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
/*
2007-11-15 22:14:46 +01:00
* We don't bother to check ownership of the parent table --- ownership of
* the child is presumed enough rights.
*/
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
/*
2007-11-15 22:14:46 +01:00
* Find and destroy the pg_inherits entry linking the two, or error out if
* there is none.
*/
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
catalogRelation = heap_open(InheritsRelationId, RowExclusiveLock);
ScanKeyInit(&key[0],
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
Anum_pg_inherits_inhrelid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(RelationGetRelid(rel)));
scan = systable_beginscan(catalogRelation, InheritsRelidSeqnoIndexId,
true, SnapshotNow, 1, key);
while (HeapTupleIsValid(inheritsTuple = systable_getnext(scan)))
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
{
Oid inhparent;
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
inhparent = ((Form_pg_inherits) GETSTRUCT(inheritsTuple))->inhparent;
if (inhparent == RelationGetRelid(parent_rel))
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
{
simple_heap_delete(catalogRelation, &inheritsTuple->t_self);
found = true;
break;
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
}
}
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
systable_endscan(scan);
heap_close(catalogRelation, RowExclusiveLock);
if (!found)
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_TABLE),
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
errmsg("relation \"%s\" is not a parent of relation \"%s\"",
RelationGetRelationName(parent_rel),
RelationGetRelationName(rel))));
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
/*
* Search through child columns looking for ones matching parent rel
*/
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
catalogRelation = heap_open(AttributeRelationId, RowExclusiveLock);
ScanKeyInit(&key[0],
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
Anum_pg_attribute_attrelid,
BTEqualStrategyNumber, F_OIDEQ,
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
ObjectIdGetDatum(RelationGetRelid(rel)));
scan = systable_beginscan(catalogRelation, AttributeRelidNumIndexId,
true, SnapshotNow, 1, key);
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
while (HeapTupleIsValid(attributeTuple = systable_getnext(scan)))
{
Form_pg_attribute att = (Form_pg_attribute) GETSTRUCT(attributeTuple);
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
/* Ignore if dropped or not inherited */
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
if (att->attisdropped)
continue;
if (att->attinhcount <= 0)
continue;
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
if (SearchSysCacheExistsAttName(RelationGetRelid(parent_rel),
NameStr(att->attname)))
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
{
/* Decrement inhcount and possibly set islocal to true */
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
HeapTuple copyTuple = heap_copytuple(attributeTuple);
Form_pg_attribute copy_att = (Form_pg_attribute) GETSTRUCT(copyTuple);
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
copy_att->attinhcount--;
if (copy_att->attinhcount == 0)
copy_att->attislocal = true;
simple_heap_update(catalogRelation, &copyTuple->t_self, copyTuple);
CatalogUpdateIndexes(catalogRelation, copyTuple);
heap_freetuple(copyTuple);
}
}
systable_endscan(scan);
heap_close(catalogRelation, RowExclusiveLock);
/*
* Likewise, find inherited check constraints and disinherit them. To do
* this, we first need a list of the names of the parent's check
* constraints. (We cheat a bit by only checking for name matches,
* assuming that the expressions will match.)
*/
catalogRelation = heap_open(ConstraintRelationId, RowExclusiveLock);
ScanKeyInit(&key[0],
Anum_pg_constraint_conrelid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(RelationGetRelid(parent_rel)));
scan = systable_beginscan(catalogRelation, ConstraintRelidIndexId,
true, SnapshotNow, 1, key);
connames = NIL;
while (HeapTupleIsValid(constraintTuple = systable_getnext(scan)))
{
Form_pg_constraint con = (Form_pg_constraint) GETSTRUCT(constraintTuple);
if (con->contype == CONSTRAINT_CHECK)
connames = lappend(connames, pstrdup(NameStr(con->conname)));
}
systable_endscan(scan);
/* Now scan the child's constraints */
ScanKeyInit(&key[0],
Anum_pg_constraint_conrelid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(RelationGetRelid(rel)));
scan = systable_beginscan(catalogRelation, ConstraintRelidIndexId,
true, SnapshotNow, 1, key);
while (HeapTupleIsValid(constraintTuple = systable_getnext(scan)))
{
Form_pg_constraint con = (Form_pg_constraint) GETSTRUCT(constraintTuple);
bool match;
ListCell *lc;
if (con->contype != CONSTRAINT_CHECK)
continue;
match = false;
foreach(lc, connames)
{
if (strcmp(NameStr(con->conname), (char *) lfirst(lc)) == 0)
{
match = true;
break;
}
}
if (match)
{
/* Decrement inhcount and possibly set islocal to true */
HeapTuple copyTuple = heap_copytuple(constraintTuple);
Form_pg_constraint copy_con = (Form_pg_constraint) GETSTRUCT(copyTuple);
if (copy_con->coninhcount <= 0) /* shouldn't happen */
elog(ERROR, "relation %u has non-inherited constraint \"%s\"",
RelationGetRelid(rel), NameStr(copy_con->conname));
copy_con->coninhcount--;
if (copy_con->coninhcount == 0)
copy_con->conislocal = true;
simple_heap_update(catalogRelation, &copyTuple->t_self, copyTuple);
CatalogUpdateIndexes(catalogRelation, copyTuple);
heap_freetuple(copyTuple);
}
}
systable_endscan(scan);
heap_close(catalogRelation, RowExclusiveLock);
drop_parent_dependency(RelationGetRelid(rel),
RelationRelationId,
RelationGetRelid(parent_rel));
/*
* Post alter hook of this inherits. Since object_access_hook doesn't take
* multiple object identifiers, we relay oid of parent relation using
* auxiliary_id argument.
*/
InvokeObjectPostAlterHookArg(InheritsRelationId,
RelationGetRelid(rel), 0,
RelationGetRelid(parent_rel), false);
/* keep our lock on the parent relation until commit */
heap_close(parent_rel, NoLock);
}
/*
* Drop the dependency created by StoreCatalogInheritance1 (CREATE TABLE
* INHERITS/ALTER TABLE INHERIT -- refclassid will be RelationRelationId) or
* heap_create_with_catalog (CREATE TABLE OF/ALTER TABLE OF -- refclassid will
2011-06-09 20:32:50 +02:00
* be TypeRelationId). There's no convenient way to do this, so go trawling
* through pg_depend.
*/
static void
drop_parent_dependency(Oid relid, Oid refclassid, Oid refobjid)
{
Relation catalogRelation;
SysScanDesc scan;
ScanKeyData key[3];
HeapTuple depTuple;
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
catalogRelation = heap_open(DependRelationId, RowExclusiveLock);
ScanKeyInit(&key[0],
Anum_pg_depend_classid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(RelationRelationId));
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
ScanKeyInit(&key[1],
Anum_pg_depend_objid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(relid));
ScanKeyInit(&key[2],
Anum_pg_depend_objsubid,
BTEqualStrategyNumber, F_INT4EQ,
Int32GetDatum(0));
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
scan = systable_beginscan(catalogRelation, DependDependerIndexId, true,
SnapshotNow, 3, key);
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
while (HeapTupleIsValid(depTuple = systable_getnext(scan)))
{
Form_pg_depend dep = (Form_pg_depend) GETSTRUCT(depTuple);
if (dep->refclassid == refclassid &&
dep->refobjid == refobjid &&
dep->refobjsubid == 0 &&
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
dep->deptype == DEPENDENCY_NORMAL)
simple_heap_delete(catalogRelation, &depTuple->t_self);
}
systable_endscan(scan);
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
heap_close(catalogRelation, RowExclusiveLock);
}
/*
* ALTER TABLE OF
*
* Attach a table to a composite type, as though it had been created with CREATE
* TABLE OF. All attname, atttypid, atttypmod and attcollation must match. The
* subject table must not have inheritance parents. These restrictions ensure
* that you cannot create a configuration impossible with CREATE TABLE OF alone.
*/
static void
ATExecAddOf(Relation rel, const TypeName *ofTypename, LOCKMODE lockmode)
{
Oid relid = RelationGetRelid(rel);
Type typetuple;
Oid typeid;
Relation inheritsRelation,
relationRelation;
SysScanDesc scan;
ScanKeyData key;
AttrNumber table_attno,
type_attno;
TupleDesc typeTupleDesc,
tableTupleDesc;
ObjectAddress tableobj,
typeobj;
HeapTuple classtuple;
/* Validate the type. */
typetuple = typenameType(NULL, ofTypename, NULL);
check_of_type(typetuple);
typeid = HeapTupleGetOid(typetuple);
/* Fail if the table has any inheritance parents. */
inheritsRelation = heap_open(InheritsRelationId, AccessShareLock);
ScanKeyInit(&key,
Anum_pg_inherits_inhrelid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(relid));
scan = systable_beginscan(inheritsRelation, InheritsRelidSeqnoIndexId,
true, SnapshotNow, 1, &key);
if (HeapTupleIsValid(systable_getnext(scan)))
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("typed tables cannot inherit")));
systable_endscan(scan);
heap_close(inheritsRelation, AccessShareLock);
/*
* Check the tuple descriptors for compatibility. Unlike inheritance, we
* require that the order also match. However, attnotnull need not match.
* Also unlike inheritance, we do not require matching relhasoids.
*/
typeTupleDesc = lookup_rowtype_tupdesc(typeid, -1);
tableTupleDesc = RelationGetDescr(rel);
table_attno = 1;
for (type_attno = 1; type_attno <= typeTupleDesc->natts; type_attno++)
{
Form_pg_attribute type_attr,
table_attr;
const char *type_attname,
*table_attname;
/* Get the next non-dropped type attribute. */
type_attr = typeTupleDesc->attrs[type_attno - 1];
if (type_attr->attisdropped)
continue;
type_attname = NameStr(type_attr->attname);
/* Get the next non-dropped table attribute. */
do
{
if (table_attno > tableTupleDesc->natts)
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
errmsg("table is missing column \"%s\"",
type_attname)));
table_attr = tableTupleDesc->attrs[table_attno++ - 1];
} while (table_attr->attisdropped);
table_attname = NameStr(table_attr->attname);
/* Compare name. */
if (strncmp(table_attname, type_attname, NAMEDATALEN) != 0)
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
2011-06-09 20:32:50 +02:00
errmsg("table has column \"%s\" where type requires \"%s\"",
table_attname, type_attname)));
/* Compare type. */
if (table_attr->atttypid != type_attr->atttypid ||
table_attr->atttypmod != type_attr->atttypmod ||
table_attr->attcollation != type_attr->attcollation)
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
2011-06-09 20:32:50 +02:00
errmsg("table \"%s\" has different type for column \"%s\"",
RelationGetRelationName(rel), type_attname)));
}
DecrTupleDescRefCount(typeTupleDesc);
/* Any remaining columns at the end of the table had better be dropped. */
for (; table_attno <= tableTupleDesc->natts; table_attno++)
{
Form_pg_attribute table_attr = tableTupleDesc->attrs[table_attno - 1];
2011-06-09 20:32:50 +02:00
if (!table_attr->attisdropped)
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
errmsg("table has extra column \"%s\"",
NameStr(table_attr->attname))));
}
/* If the table was already typed, drop the existing dependency. */
if (rel->rd_rel->reloftype)
drop_parent_dependency(relid, TypeRelationId, rel->rd_rel->reloftype);
/* Record a dependency on the new type. */
tableobj.classId = RelationRelationId;
tableobj.objectId = relid;
tableobj.objectSubId = 0;
typeobj.classId = TypeRelationId;
typeobj.objectId = typeid;
typeobj.objectSubId = 0;
recordDependencyOn(&tableobj, &typeobj, DEPENDENCY_NORMAL);
/* Update pg_class.reloftype */
relationRelation = heap_open(RelationRelationId, RowExclusiveLock);
classtuple = SearchSysCacheCopy1(RELOID, ObjectIdGetDatum(relid));
if (!HeapTupleIsValid(classtuple))
elog(ERROR, "cache lookup failed for relation %u", relid);
((Form_pg_class) GETSTRUCT(classtuple))->reloftype = typeid;
simple_heap_update(relationRelation, &classtuple->t_self, classtuple);
CatalogUpdateIndexes(relationRelation, classtuple);
InvokeObjectPostAlterHook(RelationRelationId, relid, 0);
heap_freetuple(classtuple);
heap_close(relationRelation, RowExclusiveLock);
ReleaseSysCache(typetuple);
}
/*
* ALTER TABLE NOT OF
*
2011-06-09 20:32:50 +02:00
* Detach a typed table from its originating type. Just clear reloftype and
* remove the dependency.
*/
static void
ATExecDropOf(Relation rel, LOCKMODE lockmode)
{
Oid relid = RelationGetRelid(rel);
Relation relationRelation;
HeapTuple tuple;
if (!OidIsValid(rel->rd_rel->reloftype))
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("\"%s\" is not a typed table",
RelationGetRelationName(rel))));
/*
2011-06-09 20:32:50 +02:00
* We don't bother to check ownership of the type --- ownership of the
* table is presumed enough rights. No lock required on the type, either.
*/
drop_parent_dependency(relid, TypeRelationId, rel->rd_rel->reloftype);
/* Clear pg_class.reloftype */
relationRelation = heap_open(RelationRelationId, RowExclusiveLock);
tuple = SearchSysCacheCopy1(RELOID, ObjectIdGetDatum(relid));
if (!HeapTupleIsValid(tuple))
elog(ERROR, "cache lookup failed for relation %u", relid);
((Form_pg_class) GETSTRUCT(tuple))->reloftype = InvalidOid;
simple_heap_update(relationRelation, &tuple->t_self, tuple);
CatalogUpdateIndexes(relationRelation, tuple);
InvokeObjectPostAlterHook(RelationRelationId, relid, 0);
heap_freetuple(tuple);
heap_close(relationRelation, RowExclusiveLock);
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
}
/*
* ALTER FOREIGN TABLE <name> OPTIONS (...)
*/
static void
ATExecGenericOptions(Relation rel, List *options)
{
2011-04-10 17:42:00 +02:00
Relation ftrel;
ForeignServer *server;
ForeignDataWrapper *fdw;
2011-04-10 17:42:00 +02:00
HeapTuple tuple;
bool isnull;
Datum repl_val[Natts_pg_foreign_table];
bool repl_null[Natts_pg_foreign_table];
bool repl_repl[Natts_pg_foreign_table];
Datum datum;
Form_pg_foreign_table tableform;
if (options == NIL)
return;
ftrel = heap_open(ForeignTableRelationId, RowExclusiveLock);
tuple = SearchSysCacheCopy1(FOREIGNTABLEREL, rel->rd_id);
if (!HeapTupleIsValid(tuple))
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_OBJECT),
errmsg("foreign table \"%s\" does not exist",
2011-04-10 17:42:00 +02:00
RelationGetRelationName(rel))));
tableform = (Form_pg_foreign_table) GETSTRUCT(tuple);
server = GetForeignServer(tableform->ftserver);
fdw = GetForeignDataWrapper(server->fdwid);
memset(repl_val, 0, sizeof(repl_val));
memset(repl_null, false, sizeof(repl_null));
memset(repl_repl, false, sizeof(repl_repl));
/* Extract the current options */
datum = SysCacheGetAttr(FOREIGNTABLEREL,
tuple,
Anum_pg_foreign_table_ftoptions,
&isnull);
if (isnull)
datum = PointerGetDatum(NULL);
/* Transform the options */
datum = transformGenericOptions(ForeignTableRelationId,
datum,
options,
fdw->fdwvalidator);
if (PointerIsValid(DatumGetPointer(datum)))
repl_val[Anum_pg_foreign_table_ftoptions - 1] = datum;
else
repl_null[Anum_pg_foreign_table_ftoptions - 1] = true;
repl_repl[Anum_pg_foreign_table_ftoptions - 1] = true;
/* Everything looks good - update the tuple */
tuple = heap_modify_tuple(tuple, RelationGetDescr(ftrel),
repl_val, repl_null, repl_repl);
simple_heap_update(ftrel, &tuple->t_self, tuple);
CatalogUpdateIndexes(ftrel, tuple);
InvokeObjectPostAlterHook(ForeignTableRelationId,
RelationGetRelid(rel), 0);
heap_close(ftrel, RowExclusiveLock);
heap_freetuple(tuple);
}
/*
* Execute ALTER TABLE SET SCHEMA
*/
Oid
AlterTableNamespace(AlterObjectSchemaStmt *stmt)
{
Relation rel;
Oid relid;
Oid oldNspOid;
Oid nspOid;
RangeVar *newrv;
ObjectAddresses *objsMoved;
relid = RangeVarGetRelidExtended(stmt->relation, AccessExclusiveLock,
stmt->missing_ok, false,
RangeVarCallbackForAlterRelation,
(void *) stmt);
if (!OidIsValid(relid))
{
ereport(NOTICE,
(errmsg("relation \"%s\" does not exist, skipping",
stmt->relation->relname)));
return InvalidOid;
}
rel = relation_open(relid, NoLock);
oldNspOid = RelationGetNamespace(rel);
/* If it's an owned sequence, disallow moving it by itself. */
if (rel->rd_rel->relkind == RELKIND_SEQUENCE)
{
Oid tableId;
int32 colId;
if (sequenceIsOwned(relid, &tableId, &colId))
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot move an owned sequence into another schema"),
errdetail("Sequence \"%s\" is linked to table \"%s\".",
RelationGetRelationName(rel),
get_rel_name(tableId))));
}
/* Get and lock schema OID and check its permissions. */
newrv = makeRangeVar(stmt->newschema, RelationGetRelationName(rel), -1);
nspOid = RangeVarGetAndCheckCreationNamespace(newrv, NoLock, NULL);
/* common checks on switching namespaces */
CheckSetNamespace(oldNspOid, nspOid, RelationRelationId, relid);
objsMoved = new_object_addresses();
AlterTableNamespaceInternal(rel, oldNspOid, nspOid, objsMoved);
free_object_addresses(objsMoved);
/* close rel, but keep lock until commit */
relation_close(rel, NoLock);
return relid;
}
/*
* The guts of relocating a table or materialized view to another namespace:
* besides moving the relation itself, its dependent objects are relocated to
* the new schema.
*/
void
AlterTableNamespaceInternal(Relation rel, Oid oldNspOid, Oid nspOid,
ObjectAddresses *objsMoved)
{
Relation classRel;
Assert(objsMoved != NULL);
/* OK, modify the pg_class row and pg_depend entry */
classRel = heap_open(RelationRelationId, RowExclusiveLock);
AlterRelationNamespaceInternal(classRel, RelationGetRelid(rel), oldNspOid,
nspOid, true, objsMoved);
/* Fix the table's row type too */
AlterTypeNamespaceInternal(rel->rd_rel->reltype,
nspOid, false, false, objsMoved);
/* Fix other dependent stuff */
if (rel->rd_rel->relkind == RELKIND_RELATION ||
rel->rd_rel->relkind == RELKIND_MATVIEW)
{
AlterIndexNamespaces(classRel, rel, oldNspOid, nspOid, objsMoved);
AlterSeqNamespaces(classRel, rel, oldNspOid, nspOid,
objsMoved, AccessExclusiveLock);
AlterConstraintNamespaces(RelationGetRelid(rel), oldNspOid, nspOid,
false, objsMoved);
}
heap_close(classRel, RowExclusiveLock);
}
/*
* The guts of relocating a relation to another namespace: fix the pg_class
* entry, and the pg_depend entry if any. Caller must already have
* opened and write-locked pg_class.
*/
void
AlterRelationNamespaceInternal(Relation classRel, Oid relOid,
Oid oldNspOid, Oid newNspOid,
bool hasDependEntry, ObjectAddresses *objsMoved)
{
2005-10-15 04:49:52 +02:00
HeapTuple classTup;
Form_pg_class classForm;
ObjectAddress thisobj;
classTup = SearchSysCacheCopy1(RELOID, ObjectIdGetDatum(relOid));
if (!HeapTupleIsValid(classTup))
elog(ERROR, "cache lookup failed for relation %u", relOid);
classForm = (Form_pg_class) GETSTRUCT(classTup);
Assert(classForm->relnamespace == oldNspOid);
thisobj.classId = RelationRelationId;
thisobj.objectId = relOid;
thisobj.objectSubId = 0;
/*
* Do nothing when there's nothing to do.
*/
if (!object_address_present(&thisobj, objsMoved))
{
/* check for duplicate name (more friendly than unique-index failure) */
if (get_relname_relid(NameStr(classForm->relname),
newNspOid) != InvalidOid)
ereport(ERROR,
(errcode(ERRCODE_DUPLICATE_TABLE),
errmsg("relation \"%s\" already exists in schema \"%s\"",
NameStr(classForm->relname),
get_namespace_name(newNspOid))));
/* classTup is a copy, so OK to scribble on */
classForm->relnamespace = newNspOid;
simple_heap_update(classRel, &classTup->t_self, classTup);
CatalogUpdateIndexes(classRel, classTup);
/* Update dependency on schema if caller said so */
if (hasDependEntry &&
changeDependencyFor(RelationRelationId, relOid,
NamespaceRelationId, oldNspOid, newNspOid) != 1)
elog(ERROR, "failed to change schema dependency for relation \"%s\"",
NameStr(classForm->relname));
add_exact_object_address(&thisobj, objsMoved);
InvokeObjectPostAlterHook(RelationRelationId, relOid, 0);
}
heap_freetuple(classTup);
}
/*
* Move all indexes for the specified relation to another namespace.
*
* Note: we assume adequate permission checking was done by the caller,
* and that the caller has a suitable lock on the owning relation.
*/
static void
AlterIndexNamespaces(Relation classRel, Relation rel,
Oid oldNspOid, Oid newNspOid, ObjectAddresses *objsMoved)
{
List *indexList;
ListCell *l;
indexList = RelationGetIndexList(rel);
foreach(l, indexList)
{
2005-10-15 04:49:52 +02:00
Oid indexOid = lfirst_oid(l);
ObjectAddress thisobj;
thisobj.classId = RelationRelationId;
thisobj.objectId = indexOid;
thisobj.objectSubId = 0;
/*
2005-10-15 04:49:52 +02:00
* Note: currently, the index will not have its own dependency on the
* namespace, so we don't need to do changeDependencyFor(). There's no
* row type in pg_type, either.
*
* XXX this objsMoved test may be pointless -- surely we have a single
* dependency link from a relation to each index?
*/
if (!object_address_present(&thisobj, objsMoved))
{
AlterRelationNamespaceInternal(classRel, indexOid,
oldNspOid, newNspOid,
false, objsMoved);
add_exact_object_address(&thisobj, objsMoved);
}
}
list_free(indexList);
}
/*
* Move all SERIAL-column sequences of the specified relation to another
* namespace.
*
* Note: we assume adequate permission checking was done by the caller,
* and that the caller has a suitable lock on the owning relation.
*/
static void
AlterSeqNamespaces(Relation classRel, Relation rel,
Oid oldNspOid, Oid newNspOid, ObjectAddresses *objsMoved,
LOCKMODE lockmode)
{
Relation depRel;
SysScanDesc scan;
2005-10-15 04:49:52 +02:00
ScanKeyData key[2];
HeapTuple tup;
/*
* SERIAL sequences are those having an auto dependency on one of the
2005-10-15 04:49:52 +02:00
* table's columns (we don't care *which* column, exactly).
*/
depRel = heap_open(DependRelationId, AccessShareLock);
ScanKeyInit(&key[0],
Anum_pg_depend_refclassid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(RelationRelationId));
ScanKeyInit(&key[1],
Anum_pg_depend_refobjid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(RelationGetRelid(rel)));
/* we leave refobjsubid unspecified */
scan = systable_beginscan(depRel, DependReferenceIndexId, true,
SnapshotNow, 2, key);
while (HeapTupleIsValid(tup = systable_getnext(scan)))
{
Form_pg_depend depForm = (Form_pg_depend) GETSTRUCT(tup);
Relation seqRel;
/* skip dependencies other than auto dependencies on columns */
if (depForm->refobjsubid == 0 ||
depForm->classid != RelationRelationId ||
depForm->objsubid != 0 ||
depForm->deptype != DEPENDENCY_AUTO)
continue;
/* Use relation_open just in case it's an index */
seqRel = relation_open(depForm->objid, lockmode);
/* skip non-sequence relations */
if (RelationGetForm(seqRel)->relkind != RELKIND_SEQUENCE)
{
/* No need to keep the lock */
relation_close(seqRel, lockmode);
continue;
}
/* Fix the pg_class and pg_depend entries */
AlterRelationNamespaceInternal(classRel, depForm->objid,
oldNspOid, newNspOid,
true, objsMoved);
2005-10-15 04:49:52 +02:00
/*
2005-10-15 04:49:52 +02:00
* Sequences have entries in pg_type. We need to be careful to move
* them to the new namespace, too.
*/
AlterTypeNamespaceInternal(RelationGetForm(seqRel)->reltype,
newNspOid, false, false, objsMoved);
/* Now we can close it. Keep the lock till end of transaction. */
relation_close(seqRel, NoLock);
}
systable_endscan(scan);
relation_close(depRel, AccessShareLock);
}
/*
* This code supports
* CREATE TEMP TABLE ... ON COMMIT { DROP | PRESERVE ROWS | DELETE ROWS }
*
* Because we only support this for TEMP tables, it's sufficient to remember
* the state in a backend-local data structure.
*/
/*
* Register a newly-created relation's ON COMMIT action.
*/
void
register_on_commit_action(Oid relid, OnCommitAction action)
{
2003-08-04 02:43:34 +02:00
OnCommitItem *oc;
MemoryContext oldcxt;
/*
2005-10-15 04:49:52 +02:00
* We needn't bother registering the relation unless there is an ON COMMIT
* action we need to take.
*/
if (action == ONCOMMIT_NOOP || action == ONCOMMIT_PRESERVE_ROWS)
return;
oldcxt = MemoryContextSwitchTo(CacheMemoryContext);
oc = (OnCommitItem *) palloc(sizeof(OnCommitItem));
oc->relid = relid;
oc->oncommit = action;
oc->creating_subid = GetCurrentSubTransactionId();
oc->deleting_subid = InvalidSubTransactionId;
on_commits = lcons(oc, on_commits);
MemoryContextSwitchTo(oldcxt);
}
/*
* Unregister any ON COMMIT action when a relation is deleted.
*
* Actually, we only mark the OnCommitItem entry as to be deleted after commit.
*/
void
remove_on_commit_action(Oid relid)
{
ListCell *l;
foreach(l, on_commits)
{
2003-08-04 02:43:34 +02:00
OnCommitItem *oc = (OnCommitItem *) lfirst(l);
if (oc->relid == relid)
{
oc->deleting_subid = GetCurrentSubTransactionId();
break;
}
}
}
/*
* Perform ON COMMIT actions.
*
* This is invoked just before actually committing, since it's possible
* to encounter errors.
*/
void
PreCommit_on_commit_actions(void)
{
ListCell *l;
List *oids_to_truncate = NIL;
foreach(l, on_commits)
{
2003-08-04 02:43:34 +02:00
OnCommitItem *oc = (OnCommitItem *) lfirst(l);
/* Ignore entry if already dropped in this xact */
if (oc->deleting_subid != InvalidSubTransactionId)
continue;
switch (oc->oncommit)
{
case ONCOMMIT_NOOP:
case ONCOMMIT_PRESERVE_ROWS:
/* Do nothing (there shouldn't be such entries, actually) */
break;
case ONCOMMIT_DELETE_ROWS:
/*
* If this transaction hasn't accessed any temporary
* relations, we can skip truncating ON COMMIT DELETE ROWS
* tables, as they must still be empty.
*/
if (MyXactAccessedTempRel)
oids_to_truncate = lappend_oid(oids_to_truncate, oc->relid);
break;
case ONCOMMIT_DROP:
2003-08-04 02:43:34 +02:00
{
ObjectAddress object;
object.classId = RelationRelationId;
2003-08-04 02:43:34 +02:00
object.objectId = oc->relid;
object.objectSubId = 0;
/*
* Since this is an automatic drop, rather than one
* directly initiated by the user, we pass the
* PERFORM_DELETION_INTERNAL flag.
*/
performDeletion(&object,
DROP_CASCADE, PERFORM_DELETION_INTERNAL);
2003-08-04 02:43:34 +02:00
/*
* Note that table deletion will call
2005-10-15 04:49:52 +02:00
* remove_on_commit_action, so the entry should get marked
* as deleted.
2003-08-04 02:43:34 +02:00
*/
Assert(oc->deleting_subid != InvalidSubTransactionId);
2003-08-04 02:43:34 +02:00
break;
}
}
}
if (oids_to_truncate != NIL)
{
heap_truncate(oids_to_truncate);
2005-10-15 04:49:52 +02:00
CommandCounterIncrement(); /* XXX needed? */
}
}
/*
* Post-commit or post-abort cleanup for ON COMMIT management.
*
* All we do here is remove no-longer-needed OnCommitItem entries.
*
* During commit, remove entries that were deleted during this transaction;
* during abort, remove those created during this transaction.
*/
void
AtEOXact_on_commit_actions(bool isCommit)
{
2004-08-29 07:07:03 +02:00
ListCell *cur_item;
ListCell *prev_item;
prev_item = NULL;
cur_item = list_head(on_commits);
while (cur_item != NULL)
{
OnCommitItem *oc = (OnCommitItem *) lfirst(cur_item);
if (isCommit ? oc->deleting_subid != InvalidSubTransactionId :
oc->creating_subid != InvalidSubTransactionId)
{
/* cur_item must be removed */
on_commits = list_delete_cell(on_commits, cur_item, prev_item);
pfree(oc);
if (prev_item)
cur_item = lnext(prev_item);
else
cur_item = list_head(on_commits);
}
else
{
/* cur_item must be preserved */
oc->creating_subid = InvalidSubTransactionId;
oc->deleting_subid = InvalidSubTransactionId;
prev_item = cur_item;
cur_item = lnext(prev_item);
}
}
}
/*
* Post-subcommit or post-subabort cleanup for ON COMMIT management.
*
* During subabort, we can immediately remove entries created during this
2004-08-29 07:07:03 +02:00
* subtransaction. During subcommit, just relabel entries marked during
* this subtransaction as being the parent's responsibility.
*/
void
AtEOSubXact_on_commit_actions(bool isCommit, SubTransactionId mySubid,
SubTransactionId parentSubid)
{
2004-08-29 07:07:03 +02:00
ListCell *cur_item;
ListCell *prev_item;
prev_item = NULL;
cur_item = list_head(on_commits);
while (cur_item != NULL)
{
OnCommitItem *oc = (OnCommitItem *) lfirst(cur_item);
if (!isCommit && oc->creating_subid == mySubid)
{
/* cur_item must be removed */
on_commits = list_delete_cell(on_commits, cur_item, prev_item);
pfree(oc);
if (prev_item)
cur_item = lnext(prev_item);
else
cur_item = list_head(on_commits);
}
else
{
/* cur_item must be preserved */
if (oc->creating_subid == mySubid)
oc->creating_subid = parentSubid;
if (oc->deleting_subid == mySubid)
oc->deleting_subid = isCommit ? parentSubid : InvalidSubTransactionId;
prev_item = cur_item;
cur_item = lnext(prev_item);
}
}
}
/*
* This is intended as a callback for RangeVarGetRelidExtended(). It allows
* the relation to be locked only if (1) it's a plain table, materialized
* view, or TOAST table and (2) the current user is the owner (or the
* superuser). This meets the permission-checking needs of CLUSTER, REINDEX
* TABLE, and REFRESH MATERIALIZED VIEW; we expose it here so that it can be
* used by all.
*/
void
RangeVarCallbackOwnsTable(const RangeVar *relation,
Oid relId, Oid oldRelId, void *arg)
{
char relkind;
/* Nothing to do if the relation was not found. */
if (!OidIsValid(relId))
return;
/*
* If the relation does exist, check whether it's an index. But note that
* the relation might have been dropped between the time we did the name
* lookup and now. In that case, there's nothing to do.
*/
relkind = get_rel_relkind(relId);
if (!relkind)
return;
if (relkind != RELKIND_RELATION && relkind != RELKIND_TOASTVALUE &&
relkind != RELKIND_MATVIEW)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("\"%s\" is not a table or materialized view", relation->relname)));
/* Check permissions */
if (!pg_class_ownercheck(relId, GetUserId()))
aclcheck_error(ACLCHECK_NOT_OWNER, ACL_KIND_CLASS, relation->relname);
}
/*
* Common RangeVarGetRelid callback for rename, set schema, and alter table
* processing.
*/
static void
RangeVarCallbackForAlterRelation(const RangeVar *rv, Oid relid, Oid oldrelid,
void *arg)
{
Node *stmt = (Node *) arg;
ObjectType reltype;
HeapTuple tuple;
Form_pg_class classform;
AclResult aclresult;
char relkind;
tuple = SearchSysCache1(RELOID, ObjectIdGetDatum(relid));
if (!HeapTupleIsValid(tuple))
return; /* concurrently dropped */
classform = (Form_pg_class) GETSTRUCT(tuple);
relkind = classform->relkind;
/* Must own relation. */
if (!pg_class_ownercheck(relid, GetUserId()))
aclcheck_error(ACLCHECK_NOT_OWNER, ACL_KIND_CLASS, rv->relname);
/* No system table modifications unless explicitly allowed. */
if (!allowSystemTableMods && IsSystemClass(classform))
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
errmsg("permission denied: \"%s\" is a system catalog",
rv->relname)));
/*
* Extract the specified relation type from the statement parse tree.
*
* Also, for ALTER .. RENAME, check permissions: the user must (still)
* have CREATE rights on the containing namespace.
*/
if (IsA(stmt, RenameStmt))
{
aclresult = pg_namespace_aclcheck(classform->relnamespace,
GetUserId(), ACL_CREATE);
if (aclresult != ACLCHECK_OK)
aclcheck_error(aclresult, ACL_KIND_NAMESPACE,
get_namespace_name(classform->relnamespace));
reltype = ((RenameStmt *) stmt)->renameType;
}
else if (IsA(stmt, AlterObjectSchemaStmt))
reltype = ((AlterObjectSchemaStmt *) stmt)->objectType;
else if (IsA(stmt, AlterTableStmt))
reltype = ((AlterTableStmt *) stmt)->relkind;
else
{
reltype = OBJECT_TABLE; /* placate compiler */
elog(ERROR, "unrecognized node type: %d", (int) nodeTag(stmt));
}
/*
* For compatibility with prior releases, we allow ALTER TABLE to be used
* with most other types of relations (but not composite types). We allow
* similar flexibility for ALTER INDEX in the case of RENAME, but not
* otherwise. Otherwise, the user must select the correct form of the
* command for the relation at issue.
*/
if (reltype == OBJECT_SEQUENCE && relkind != RELKIND_SEQUENCE)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("\"%s\" is not a sequence", rv->relname)));
if (reltype == OBJECT_VIEW && relkind != RELKIND_VIEW)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("\"%s\" is not a view", rv->relname)));
if (reltype == OBJECT_MATVIEW && relkind != RELKIND_MATVIEW)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("\"%s\" is not a materialized view", rv->relname)));
if (reltype == OBJECT_FOREIGN_TABLE && relkind != RELKIND_FOREIGN_TABLE)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("\"%s\" is not a foreign table", rv->relname)));
if (reltype == OBJECT_TYPE && relkind != RELKIND_COMPOSITE_TYPE)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("\"%s\" is not a composite type", rv->relname)));
if (reltype == OBJECT_INDEX && relkind != RELKIND_INDEX
&& !IsA(stmt, RenameStmt))
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("\"%s\" is not an index", rv->relname)));
/*
* Don't allow ALTER TABLE on composite types. We want people to use ALTER
* TYPE for that.
*/
if (reltype != OBJECT_TYPE && relkind == RELKIND_COMPOSITE_TYPE)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("\"%s\" is a composite type", rv->relname),
errhint("Use ALTER TYPE instead.")));
/*
* Don't allow ALTER TABLE .. SET SCHEMA on relations that can't be moved
* to a different schema, such as indexes and TOAST tables.
*/
if (IsA(stmt, AlterObjectSchemaStmt) &&
relkind != RELKIND_RELATION &&
relkind != RELKIND_VIEW &&
relkind != RELKIND_MATVIEW &&
relkind != RELKIND_SEQUENCE &&
relkind != RELKIND_FOREIGN_TABLE)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("\"%s\" is not a table, view, sequence, or foreign table",
rv->relname)));
ReleaseSysCache(tuple);
}