5972 lines
168 KiB
C
5972 lines
168 KiB
C
/*-------------------------------------------------------------------------
|
|
*
|
|
* tablecmds.c
|
|
* Commands for creating and altering table structures and settings
|
|
*
|
|
* Portions Copyright (c) 1996-2004, PostgreSQL Global Development Group
|
|
* Portions Copyright (c) 1994, Regents of the University of California
|
|
*
|
|
*
|
|
* IDENTIFICATION
|
|
* $PostgreSQL: pgsql/src/backend/commands/tablecmds.c,v 1.128 2004/08/29 04:12:30 momjian Exp $
|
|
*
|
|
*-------------------------------------------------------------------------
|
|
*/
|
|
#include "postgres.h"
|
|
|
|
#include "access/genam.h"
|
|
#include "access/tuptoaster.h"
|
|
#include "catalog/catalog.h"
|
|
#include "catalog/catname.h"
|
|
#include "catalog/dependency.h"
|
|
#include "catalog/heap.h"
|
|
#include "catalog/index.h"
|
|
#include "catalog/indexing.h"
|
|
#include "catalog/namespace.h"
|
|
#include "catalog/pg_constraint.h"
|
|
#include "catalog/pg_depend.h"
|
|
#include "catalog/pg_inherits.h"
|
|
#include "catalog/pg_namespace.h"
|
|
#include "catalog/pg_opclass.h"
|
|
#include "catalog/pg_trigger.h"
|
|
#include "catalog/pg_type.h"
|
|
#include "commands/cluster.h"
|
|
#include "commands/defrem.h"
|
|
#include "commands/tablecmds.h"
|
|
#include "commands/tablespace.h"
|
|
#include "commands/trigger.h"
|
|
#include "executor/executor.h"
|
|
#include "lib/stringinfo.h"
|
|
#include "miscadmin.h"
|
|
#include "nodes/makefuncs.h"
|
|
#include "optimizer/clauses.h"
|
|
#include "optimizer/plancat.h"
|
|
#include "optimizer/prep.h"
|
|
#include "parser/analyze.h"
|
|
#include "parser/gramparse.h"
|
|
#include "parser/parser.h"
|
|
#include "parser/parse_clause.h"
|
|
#include "parser/parse_coerce.h"
|
|
#include "parser/parse_expr.h"
|
|
#include "parser/parse_oper.h"
|
|
#include "parser/parse_relation.h"
|
|
#include "parser/parse_type.h"
|
|
#include "rewrite/rewriteHandler.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/relcache.h"
|
|
#include "utils/syscache.h"
|
|
|
|
|
|
/*
|
|
* ON COMMIT action list
|
|
*/
|
|
typedef struct OnCommitItem
|
|
{
|
|
Oid relid; /* relid of relation */
|
|
OnCommitAction oncommit; /* what to do at end of xact */
|
|
|
|
/*
|
|
* If this entry was created during this xact, it should be deleted at
|
|
* xact abort. Conversely, if this entry was deleted during this
|
|
* xact, it should be removed at xact commit. We leave deleted
|
|
* entries in the list until commit so that we can roll back if
|
|
* needed.
|
|
*/
|
|
TransactionId creating_xid;
|
|
TransactionId deleting_xid;
|
|
} 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: */
|
|
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 */
|
|
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 */
|
|
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 */
|
|
typedef struct NewConstraint
|
|
{
|
|
char *name; /* Constraint name, or NULL if none */
|
|
ConstrType contype; /* CHECK, NOT_NULL, or FOREIGN */
|
|
AttrNumber attnum; /* only relevant for NOT_NULL */
|
|
Oid refrelid; /* PK rel, if FOREIGN */
|
|
Node *qual; /* Check expr or FkConstraint struct */
|
|
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;
|
|
|
|
|
|
/* Used by attribute and relation renaming routines: */
|
|
#define RI_TRIGGER_PK 1 /* is a trigger on the PK relation */
|
|
#define RI_TRIGGER_FK 2 /* is a trigger on the FK relation */
|
|
#define RI_TRIGGER_NONE 0 /* is not an RI trigger function */
|
|
|
|
|
|
static List *MergeAttributes(List *schema, List *supers, bool istemp,
|
|
List **supOids, List **supconstr, int *supOidCount);
|
|
static bool change_varattnos_of_a_node(Node *node, const AttrNumber *newattno);
|
|
static void StoreCatalogInheritance(Oid relationId, List *supers);
|
|
static int findAttrByName(const char *attributeName, List *schema);
|
|
static void setRelhassubclassInRelation(Oid relationId, bool relhassubclass);
|
|
static bool needs_toast_table(Relation rel);
|
|
static int transformColumnNameList(Oid relId, List *colList,
|
|
int16 *attnums, Oid *atttypids);
|
|
static int transformFkeyGetPrimaryKey(Relation pkrel, Oid *indexOid,
|
|
List **attnamelist,
|
|
int16 *attnums, Oid *atttypids,
|
|
Oid *opclasses);
|
|
static Oid transformFkeyCheckAttrs(Relation pkrel,
|
|
int numattrs, int16 *attnums,
|
|
Oid *opclasses);
|
|
static void validateForeignKeyConstraint(FkConstraint *fkconstraint,
|
|
Relation rel, Relation pkrel);
|
|
static void createForeignKeyTriggers(Relation rel, FkConstraint *fkconstraint,
|
|
Oid constrOid);
|
|
static char *fkMatchTypeToString(char match_type);
|
|
static void ATController(Relation rel, List *cmds, bool recurse);
|
|
static void ATPrepCmd(List **wqueue, Relation rel, AlterTableCmd *cmd,
|
|
bool recurse, bool recursing);
|
|
static void ATRewriteCatalogs(List **wqueue);
|
|
static void ATExecCmd(AlteredTableInfo *tab, Relation rel, AlterTableCmd *cmd);
|
|
static void ATRewriteTables(List **wqueue);
|
|
static void ATRewriteTable(AlteredTableInfo *tab, Oid OIDNewHeap);
|
|
static AlteredTableInfo *ATGetQueueEntry(List **wqueue, Relation rel);
|
|
static void ATSimplePermissions(Relation rel, bool allowView);
|
|
static void ATSimpleRecursion(List **wqueue, Relation rel,
|
|
AlterTableCmd *cmd, bool recurse);
|
|
static void ATOneLevelRecursion(List **wqueue, Relation rel,
|
|
AlterTableCmd *cmd);
|
|
static void find_composite_type_dependencies(Oid typeOid,
|
|
const char *origTblName);
|
|
static void ATPrepAddColumn(List **wqueue, Relation rel, bool recurse,
|
|
AlterTableCmd *cmd);
|
|
static void ATExecAddColumn(AlteredTableInfo *tab, Relation rel,
|
|
ColumnDef *colDef);
|
|
static void add_column_datatype_dependency(Oid relid, int32 attnum, Oid typid);
|
|
static void add_column_support_dependency(Oid relid, int32 attnum,
|
|
RangeVar *support);
|
|
static void ATExecDropNotNull(Relation rel, const char *colName);
|
|
static void ATExecSetNotNull(AlteredTableInfo *tab, Relation rel,
|
|
const char *colName);
|
|
static void ATExecColumnDefault(Relation rel, const char *colName,
|
|
Node *newDefault);
|
|
static void ATPrepSetStatistics(Relation rel, const char *colName,
|
|
Node *flagValue);
|
|
static void ATExecSetStatistics(Relation rel, const char *colName,
|
|
Node *newValue);
|
|
static void ATExecSetStorage(Relation rel, const char *colName,
|
|
Node *newValue);
|
|
static void ATExecDropColumn(Relation rel, const char *colName,
|
|
DropBehavior behavior,
|
|
bool recurse, bool recursing);
|
|
static void ATExecAddIndex(AlteredTableInfo *tab, Relation rel,
|
|
IndexStmt *stmt, bool is_rebuild);
|
|
static void ATExecAddConstraint(AlteredTableInfo *tab, Relation rel,
|
|
Node *newConstraint);
|
|
static void ATAddForeignKeyConstraint(AlteredTableInfo *tab, Relation rel,
|
|
FkConstraint *fkconstraint);
|
|
static void ATPrepDropConstraint(List **wqueue, Relation rel,
|
|
bool recurse, AlterTableCmd *cmd);
|
|
static void ATExecDropConstraint(Relation rel, const char *constrName,
|
|
DropBehavior behavior, bool quiet);
|
|
static void ATPrepAlterColumnType(List **wqueue,
|
|
AlteredTableInfo *tab, Relation rel,
|
|
bool recurse, bool recursing,
|
|
AlterTableCmd *cmd);
|
|
static void ATExecAlterColumnType(AlteredTableInfo *tab, Relation rel,
|
|
const char *colName, TypeName *typename);
|
|
static void ATPostAlterTypeCleanup(List **wqueue, AlteredTableInfo *tab);
|
|
static void ATPostAlterTypeParse(char *cmd, List **wqueue);
|
|
static void ATExecChangeOwner(Oid relationOid, int32 newOwnerSysId);
|
|
static void ATExecClusterOn(Relation rel, const char *indexName);
|
|
static void ATExecDropCluster(Relation rel);
|
|
static void ATPrepSetTableSpace(AlteredTableInfo *tab, Relation rel,
|
|
char *tablespacename);
|
|
static void ATExecSetTableSpace(Oid tableOid, Oid newTableSpace);
|
|
static void copy_relation_data(Relation rel, SMgrRelation dst);
|
|
static int ri_trigger_type(Oid tgfoid);
|
|
static void update_ri_trigger_args(Oid relid,
|
|
const char *oldname,
|
|
const char *newname,
|
|
bool fk_scan,
|
|
bool update_relname);
|
|
|
|
|
|
/* ----------------------------------------------------------------
|
|
* DefineRelation
|
|
* Creates a new relation.
|
|
*
|
|
* If successful, returns the OID of the new relation.
|
|
* ----------------------------------------------------------------
|
|
*/
|
|
Oid
|
|
DefineRelation(CreateStmt *stmt, char relkind)
|
|
{
|
|
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;
|
|
ListCell *listptr;
|
|
int i;
|
|
AttrNumber attnum;
|
|
|
|
/*
|
|
* 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
|
|
*/
|
|
if (stmt->oncommit != ONCOMMIT_NOOP && !stmt->relation->istemp)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
|
|
errmsg("ON COMMIT can only be used on temporary tables")));
|
|
|
|
/*
|
|
* Look up the namespace in which we are supposed to create the
|
|
* relation. Check we have permission to create there. Skip check if
|
|
* bootstrapping, since permissions machinery may not be working yet.
|
|
*/
|
|
namespaceId = RangeVarGetCreationNamespace(stmt->relation);
|
|
|
|
if (!IsBootstrapProcessingMode())
|
|
{
|
|
AclResult aclresult;
|
|
|
|
aclresult = pg_namespace_aclcheck(namespaceId, GetUserId(),
|
|
ACL_CREATE);
|
|
if (aclresult != ACLCHECK_OK)
|
|
aclcheck_error(aclresult, ACL_KIND_NAMESPACE,
|
|
get_namespace_name(namespaceId));
|
|
}
|
|
|
|
/*
|
|
* Select tablespace to use. If not specified, use containing schema's
|
|
* default tablespace (which may in turn default to database's default).
|
|
*/
|
|
if (stmt->tablespacename)
|
|
{
|
|
AclResult aclresult;
|
|
|
|
tablespaceId = get_tablespace_oid(stmt->tablespacename);
|
|
if (!OidIsValid(tablespaceId))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_UNDEFINED_OBJECT),
|
|
errmsg("tablespace \"%s\" does not exist",
|
|
stmt->tablespacename)));
|
|
/* check permissions */
|
|
aclresult = pg_tablespace_aclcheck(tablespaceId, GetUserId(),
|
|
ACL_CREATE);
|
|
if (aclresult != ACLCHECK_OK)
|
|
aclcheck_error(aclresult, ACL_KIND_TABLESPACE,
|
|
stmt->tablespacename);
|
|
} else {
|
|
tablespaceId = get_namespace_tablespace(namespaceId);
|
|
/* note no permission check on tablespace in this case */
|
|
}
|
|
|
|
/*
|
|
* Look up inheritance ancestors and generate relation schema,
|
|
* including inherited attributes.
|
|
*/
|
|
schema = MergeAttributes(schema, stmt->inhRelations,
|
|
stmt->relation->istemp,
|
|
&inheritOids, &old_constraints, &parentOidCount);
|
|
|
|
/*
|
|
* Create a relation descriptor from the relation schema and create
|
|
* the relation. Note that in this stage only inherited (pre-cooked)
|
|
* defaults and constraints will be included into the new relation.
|
|
* (BuildDescForRelation takes care of the inherited defaults, but we
|
|
* have to copy inherited constraints here.)
|
|
*/
|
|
descriptor = BuildDescForRelation(schema);
|
|
|
|
localHasOids = interpretOidsOption(stmt->hasoids);
|
|
descriptor->tdhasoid = (localHasOids || parentOidCount > 0);
|
|
|
|
if (old_constraints != NIL)
|
|
{
|
|
ConstrCheck *check = (ConstrCheck *)
|
|
palloc0(list_length(old_constraints) * sizeof(ConstrCheck));
|
|
int ncheck = 0;
|
|
|
|
foreach(listptr, old_constraints)
|
|
{
|
|
Constraint *cdef = (Constraint *) lfirst(listptr);
|
|
bool dup = false;
|
|
|
|
if (cdef->contype != CONSTR_CHECK)
|
|
continue;
|
|
Assert(cdef->name != NULL);
|
|
Assert(cdef->raw_expr == NULL && cdef->cooked_expr != NULL);
|
|
/*
|
|
* In multiple-inheritance situations, it's possible to inherit
|
|
* the same grandparent constraint through multiple parents.
|
|
* Hence, discard inherited constraints that match as to both
|
|
* name and expression. Otherwise, gripe if the names conflict.
|
|
*/
|
|
for (i = 0; i < ncheck; i++)
|
|
{
|
|
if (strcmp(check[i].ccname, cdef->name) != 0)
|
|
continue;
|
|
if (strcmp(check[i].ccbin, cdef->cooked_expr) == 0)
|
|
{
|
|
dup = true;
|
|
break;
|
|
}
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_DUPLICATE_OBJECT),
|
|
errmsg("duplicate check constraint name \"%s\"",
|
|
cdef->name)));
|
|
}
|
|
if (!dup)
|
|
{
|
|
check[ncheck].ccname = cdef->name;
|
|
check[ncheck].ccbin = pstrdup(cdef->cooked_expr);
|
|
ncheck++;
|
|
}
|
|
}
|
|
if (ncheck > 0)
|
|
{
|
|
if (descriptor->constr == NULL)
|
|
{
|
|
descriptor->constr = (TupleConstr *) palloc(sizeof(TupleConstr));
|
|
descriptor->constr->defval = NULL;
|
|
descriptor->constr->num_defval = 0;
|
|
descriptor->constr->has_not_null = false;
|
|
}
|
|
descriptor->constr->num_check = ncheck;
|
|
descriptor->constr->check = check;
|
|
}
|
|
}
|
|
|
|
relationId = heap_create_with_catalog(relname,
|
|
namespaceId,
|
|
tablespaceId,
|
|
descriptor,
|
|
relkind,
|
|
false,
|
|
localHasOids,
|
|
parentOidCount,
|
|
stmt->oncommit,
|
|
allowSystemTableMods);
|
|
|
|
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
|
|
* 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);
|
|
|
|
/*
|
|
* 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.
|
|
*
|
|
* Another task that's conveniently done at this step is to add
|
|
* dependency links between columns and supporting relations (such as
|
|
* SERIAL sequences).
|
|
*
|
|
* First, scan schema to find new column defaults.
|
|
*/
|
|
rawDefaults = NIL;
|
|
attnum = 0;
|
|
|
|
foreach(listptr, schema)
|
|
{
|
|
ColumnDef *colDef = lfirst(listptr);
|
|
|
|
attnum++;
|
|
|
|
if (colDef->raw_default != NULL)
|
|
{
|
|
RawColumnDefault *rawEnt;
|
|
|
|
Assert(colDef->cooked_default == NULL);
|
|
|
|
rawEnt = (RawColumnDefault *) palloc(sizeof(RawColumnDefault));
|
|
rawEnt->attnum = attnum;
|
|
rawEnt->raw_default = colDef->raw_default;
|
|
rawDefaults = lappend(rawDefaults, rawEnt);
|
|
}
|
|
|
|
/* Create dependency for supporting relation for this column */
|
|
if (colDef->support != NULL)
|
|
add_column_support_dependency(relationId, attnum, colDef->support);
|
|
}
|
|
|
|
/*
|
|
* Parse and add the defaults/constraints, if any.
|
|
*/
|
|
if (rawDefaults || stmt->constraints)
|
|
AddRelationRawConstraints(rel, rawDefaults, stmt->constraints);
|
|
|
|
/*
|
|
* 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;
|
|
}
|
|
|
|
/*
|
|
* RemoveRelation
|
|
* Deletes a relation.
|
|
*/
|
|
void
|
|
RemoveRelation(const RangeVar *relation, DropBehavior behavior)
|
|
{
|
|
Oid relOid;
|
|
ObjectAddress object;
|
|
|
|
relOid = RangeVarGetRelid(relation, false);
|
|
|
|
object.classId = RelOid_pg_class;
|
|
object.objectId = relOid;
|
|
object.objectSubId = 0;
|
|
|
|
performDeletion(&object, behavior);
|
|
}
|
|
|
|
/*
|
|
* TruncateRelation
|
|
* Removes all the rows from a relation.
|
|
*/
|
|
void
|
|
TruncateRelation(const RangeVar *relation)
|
|
{
|
|
Relation rel;
|
|
Oid heap_relid;
|
|
Oid toast_relid;
|
|
|
|
/* Grab exclusive lock in preparation for truncate */
|
|
rel = heap_openrv(relation, AccessExclusiveLock);
|
|
|
|
/* 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 */
|
|
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))));
|
|
|
|
/*
|
|
* We can never allow truncation of shared or nailed-in-cache relations,
|
|
* because we can't support changing their relfilenode values.
|
|
*/
|
|
if (rel->rd_rel->relisshared || rel->rd_isnailed)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
errmsg("cannot truncate system relation \"%s\"",
|
|
RelationGetRelationName(rel))));
|
|
|
|
/*
|
|
* Don't allow truncate on temp tables of other backends ... their
|
|
* local buffer manager is not going to cope.
|
|
*/
|
|
if (isOtherTempNamespace(RelationGetNamespace(rel)))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
errmsg("cannot truncate temporary tables of other sessions")));
|
|
|
|
/*
|
|
* Don't allow truncate on tables which are referenced by foreign keys
|
|
*/
|
|
heap_truncate_check_FKs(rel);
|
|
|
|
/*
|
|
* Okay, here we go: 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.
|
|
*/
|
|
setNewRelfilenode(rel);
|
|
|
|
heap_relid = RelationGetRelid(rel);
|
|
toast_relid = rel->rd_rel->reltoastrelid;
|
|
|
|
heap_close(rel, NoLock);
|
|
|
|
/*
|
|
* The same for the toast table, if any.
|
|
*/
|
|
if (OidIsValid(toast_relid))
|
|
{
|
|
rel = relation_open(toast_relid, AccessExclusiveLock);
|
|
setNewRelfilenode(rel);
|
|
heap_close(rel, NoLock);
|
|
}
|
|
|
|
/*
|
|
* Reconstruct the indexes to match, and we're done.
|
|
*/
|
|
reindex_relation(heap_relid, true);
|
|
}
|
|
|
|
/*----------
|
|
* 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.
|
|
* 'istemp' is TRUE if we are creating a temp relation.
|
|
*
|
|
* 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, bool istemp,
|
|
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;
|
|
char *bogus_marker = "Bogus!"; /* marks conflicting
|
|
* defaults */
|
|
int child_attno;
|
|
|
|
/*
|
|
* Check for duplicate names in the explicit list of attributes.
|
|
*
|
|
* 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;
|
|
|
|
for_each_cell(rest, lnext(entry))
|
|
{
|
|
ColumnDef *restdef = lfirst(rest);
|
|
|
|
if (strcmp(coldef->colname, restdef->colname) == 0)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_DUPLICATE_COLUMN),
|
|
errmsg("column \"%s\" duplicated",
|
|
coldef->colname)));
|
|
}
|
|
}
|
|
|
|
/*
|
|
* 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;
|
|
|
|
relation = heap_openrv(parent, AccessShareLock);
|
|
|
|
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 (!istemp && isTempNamespace(RelationGetNamespace(relation)))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
|
|
errmsg("cannot inherit from temporary relation \"%s\"",
|
|
parent->relname)));
|
|
|
|
/*
|
|
* 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),
|
|
errmsg("inherited relation \"%s\" duplicated",
|
|
parent->relname)));
|
|
|
|
parentOids = lappend_oid(parentOids, RelationGetRelid(relation));
|
|
|
|
if (relation->rd_rel->relhasoids)
|
|
parentsWithOids++;
|
|
|
|
tupleDesc = RelationGetDescr(relation);
|
|
constr = tupleDesc->constr;
|
|
|
|
/*
|
|
* 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 *)
|
|
palloc(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;
|
|
TypeName *typename;
|
|
|
|
/*
|
|
* Ignore dropped columns in the parent.
|
|
*/
|
|
if (attribute->attisdropped)
|
|
{
|
|
/*
|
|
* change_varattnos_of_a_node asserts that this is greater
|
|
* than zero, so if anything tries to use it, we should
|
|
* find out.
|
|
*/
|
|
newattno[parent_attno - 1] = 0;
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
* Does it conflict with some previously inherited column?
|
|
*/
|
|
exist_attno = findAttrByName(attributeName, inhSchema);
|
|
if (exist_attno > 0)
|
|
{
|
|
/*
|
|
* Yes, try to merge the two column definitions. They must
|
|
* have the same type and typmod.
|
|
*/
|
|
ereport(NOTICE,
|
|
(errmsg("merging multiple inherited definitions of column \"%s\"",
|
|
attributeName)));
|
|
def = (ColumnDef *) list_nth(inhSchema, exist_attno - 1);
|
|
if (typenameTypeId(def->typename) != attribute->atttypid ||
|
|
def->typename->typmod != attribute->atttypmod)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_DATATYPE_MISMATCH),
|
|
errmsg("inherited column \"%s\" has a type conflict",
|
|
attributeName),
|
|
errdetail("%s versus %s",
|
|
TypeNameToString(def->typename),
|
|
format_type_be(attribute->atttypid))));
|
|
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);
|
|
typename = makeNode(TypeName);
|
|
typename->typeid = attribute->atttypid;
|
|
typename->typmod = attribute->atttypmod;
|
|
def->typename = typename;
|
|
def->inhcount = 1;
|
|
def->is_local = false;
|
|
def->is_not_null = attribute->attnotnull;
|
|
def->raw_default = NULL;
|
|
def->cooked_default = NULL;
|
|
def->constraints = NIL;
|
|
def->support = NULL;
|
|
inhSchema = lappend(inhSchema, def);
|
|
newattno[parent_attno - 1] = ++child_attno;
|
|
}
|
|
|
|
/*
|
|
* Copy default if any
|
|
*/
|
|
if (attribute->atthasdef)
|
|
{
|
|
char *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 = attrdef[i].adbin;
|
|
break;
|
|
}
|
|
}
|
|
Assert(this_default != NULL);
|
|
|
|
/*
|
|
* 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 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 = pstrdup(this_default);
|
|
else if (strcmp(def->cooked_default, this_default) != 0)
|
|
{
|
|
def->cooked_default = bogus_marker;
|
|
have_bogus_defaults = true;
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Now copy the constraints of this parent, adjusting attnos using
|
|
* the completed newattno[] map
|
|
*/
|
|
if (constr && constr->num_check > 0)
|
|
{
|
|
ConstrCheck *check = constr->check;
|
|
int i;
|
|
|
|
for (i = 0; i < constr->num_check; i++)
|
|
{
|
|
Constraint *cdef = makeNode(Constraint);
|
|
Node *expr;
|
|
|
|
cdef->contype = CONSTR_CHECK;
|
|
cdef->name = pstrdup(check[i].ccname);
|
|
cdef->raw_expr = NULL;
|
|
/* adjust varattnos of ccbin here */
|
|
expr = stringToNode(check[i].ccbin);
|
|
change_varattnos_of_a_node(expr, newattno);
|
|
cdef->cooked_expr = nodeToString(expr);
|
|
constraints = lappend(constraints, cdef);
|
|
}
|
|
}
|
|
|
|
pfree(newattno);
|
|
|
|
/*
|
|
* 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
|
|
* 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;
|
|
|
|
/*
|
|
* Yes, try to merge the two column definitions. They must
|
|
* have the same type and typmod.
|
|
*/
|
|
ereport(NOTICE,
|
|
(errmsg("merging column \"%s\" with inherited definition",
|
|
attributeName)));
|
|
def = (ColumnDef *) list_nth(inhSchema, exist_attno - 1);
|
|
if (typenameTypeId(def->typename) != typenameTypeId(newdef->typename) ||
|
|
def->typename->typmod != newdef->typename->typmod)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_DATATYPE_MISMATCH),
|
|
errmsg("column \"%s\" has a type conflict",
|
|
attributeName),
|
|
errdetail("%s versus %s",
|
|
TypeNameToString(def->typename),
|
|
TypeNameToString(newdef->typename))));
|
|
/* 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;
|
|
}
|
|
|
|
/*
|
|
* 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),
|
|
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;
|
|
}
|
|
|
|
/*
|
|
* complementary static functions for MergeAttributes().
|
|
*
|
|
* Varattnos of pg_constraint.conbin must be rewritten when subclasses inherit
|
|
* constraints from parent classes, since the inherited attributes could
|
|
* be given different column numbers in multiple-inheritance cases.
|
|
*
|
|
* Note that the passed node tree is modified in place!
|
|
*/
|
|
static bool
|
|
change_varattnos_walker(Node *node, const AttrNumber *newattno)
|
|
{
|
|
if (node == NULL)
|
|
return false;
|
|
if (IsA(node, Var))
|
|
{
|
|
Var *var = (Var *) node;
|
|
|
|
if (var->varlevelsup == 0 && var->varno == 1 &&
|
|
var->varattno > 0)
|
|
{
|
|
/*
|
|
* ??? the following may be a problem when the node is
|
|
* multiply referenced though stringToNode() doesn't create
|
|
* such a node currently.
|
|
*/
|
|
Assert(newattno[var->varattno - 1] > 0);
|
|
var->varattno = newattno[var->varattno - 1];
|
|
}
|
|
return false;
|
|
}
|
|
return expression_tree_walker(node, change_varattnos_walker,
|
|
(void *) newattno);
|
|
}
|
|
|
|
static bool
|
|
change_varattnos_of_a_node(Node *node, const AttrNumber *newattno)
|
|
{
|
|
return change_varattnos_walker(node, newattno);
|
|
}
|
|
|
|
/*
|
|
* 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;
|
|
TupleDesc desc;
|
|
int16 seqNumber;
|
|
ListCell *entry;
|
|
HeapTuple tuple;
|
|
|
|
/*
|
|
* sanity checks
|
|
*/
|
|
AssertArg(OidIsValid(relationId));
|
|
|
|
if (supers == NIL)
|
|
return;
|
|
|
|
/*
|
|
* 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_openr(InheritsRelationName, RowExclusiveLock);
|
|
desc = RelationGetDescr(relation);
|
|
|
|
seqNumber = 1;
|
|
foreach(entry, supers)
|
|
{
|
|
Oid parentOid = lfirst_oid(entry);
|
|
Datum datum[Natts_pg_inherits];
|
|
char nullarr[Natts_pg_inherits];
|
|
ObjectAddress childobject,
|
|
parentobject;
|
|
|
|
datum[0] = ObjectIdGetDatum(relationId); /* inhrel */
|
|
datum[1] = ObjectIdGetDatum(parentOid); /* inhparent */
|
|
datum[2] = Int16GetDatum(seqNumber); /* inhseqno */
|
|
|
|
nullarr[0] = ' ';
|
|
nullarr[1] = ' ';
|
|
nullarr[2] = ' ';
|
|
|
|
tuple = heap_formtuple(desc, datum, nullarr);
|
|
|
|
simple_heap_insert(relation, tuple);
|
|
|
|
CatalogUpdateIndexes(relation, tuple);
|
|
|
|
heap_freetuple(tuple);
|
|
|
|
/*
|
|
* Store a dependency too
|
|
*/
|
|
parentobject.classId = RelOid_pg_class;
|
|
parentobject.objectId = parentOid;
|
|
parentobject.objectSubId = 0;
|
|
childobject.classId = RelOid_pg_class;
|
|
childobject.objectId = relationId;
|
|
childobject.objectSubId = 0;
|
|
|
|
recordDependencyOn(&childobject, &parentobject, DEPENDENCY_NORMAL);
|
|
|
|
/*
|
|
* Mark the parent as having subclasses.
|
|
*/
|
|
setRelhassubclassInRelation(parentOid, true);
|
|
|
|
seqNumber += 1;
|
|
}
|
|
|
|
heap_close(relation, RowExclusiveLock);
|
|
}
|
|
|
|
/*
|
|
* 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;
|
|
}
|
|
|
|
/*
|
|
* Update a relation's pg_class.relhassubclass entry to the given value
|
|
*/
|
|
static void
|
|
setRelhassubclassInRelation(Oid relationId, bool relhassubclass)
|
|
{
|
|
Relation relationRelation;
|
|
HeapTuple tuple;
|
|
Form_pg_class classtuple;
|
|
|
|
/*
|
|
* Fetch a modifiable copy of the tuple, modify it, update pg_class.
|
|
*
|
|
* If the tuple already has the right relhassubclass setting, we
|
|
* don't need to update it, but we still need to issue an SI inval
|
|
* message.
|
|
*/
|
|
relationRelation = heap_openr(RelationRelationName, RowExclusiveLock);
|
|
tuple = SearchSysCacheCopy(RELOID,
|
|
ObjectIdGetDatum(relationId),
|
|
0, 0, 0);
|
|
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 - changes the name of a attribute in a relation
|
|
*
|
|
* Attname attribute is changed in attribute catalog.
|
|
* No record of the previous attname is kept (correct?).
|
|
*
|
|
* get proper relrelation from relation catalog (if not arg)
|
|
* scan attribute catalog
|
|
* for name conflict (within rel)
|
|
* for original attribute (if not arg)
|
|
* modify attname in attribute tuple
|
|
* insert modified attribute in attribute catalog
|
|
* delete original attribute from attribute catalog
|
|
*/
|
|
void
|
|
renameatt(Oid myrelid,
|
|
const char *oldattname,
|
|
const char *newattname,
|
|
bool recurse,
|
|
bool recursing)
|
|
{
|
|
Relation targetrelation;
|
|
Relation attrelation;
|
|
HeapTuple atttup;
|
|
Form_pg_attribute attform;
|
|
int attnum;
|
|
List *indexoidlist;
|
|
ListCell *indexoidscan;
|
|
|
|
/*
|
|
* Grab an exclusive lock on the target table, which we will NOT
|
|
* release until end of transaction.
|
|
*/
|
|
targetrelation = relation_open(myrelid, AccessExclusiveLock);
|
|
|
|
/*
|
|
* permissions checking. this would normally be done in utility.c,
|
|
* but this particular routine is recursive.
|
|
*
|
|
* normally, only the owner of a class can change its schema.
|
|
*/
|
|
if (!pg_class_ownercheck(myrelid, GetUserId()))
|
|
aclcheck_error(ACLCHECK_NOT_OWNER, ACL_KIND_CLASS,
|
|
RelationGetRelationName(targetrelation));
|
|
if (!allowSystemTableMods && IsSystemRelation(targetrelation))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
|
|
errmsg("permission denied: \"%s\" is a system catalog",
|
|
RelationGetRelationName(targetrelation))));
|
|
|
|
/*
|
|
* 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)
|
|
{
|
|
ListCell *child;
|
|
List *children;
|
|
|
|
/* this routine is actually in the planner */
|
|
children = find_all_inheritors(myrelid);
|
|
|
|
/*
|
|
* 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);
|
|
|
|
if (childrelid == myrelid)
|
|
continue;
|
|
/* note we need not recurse again */
|
|
renameatt(childrelid, oldattname, newattname, false, true);
|
|
}
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* If we are told not to recurse, there had better not be any
|
|
* child tables; else the rename would put them out of step.
|
|
*/
|
|
if (!recursing &&
|
|
find_inheritance_children(myrelid) != NIL)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
|
|
errmsg("inherited column \"%s\" must be renamed in child tables too",
|
|
oldattname)));
|
|
}
|
|
|
|
attrelation = heap_openr(AttributeRelationName, RowExclusiveLock);
|
|
|
|
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)));
|
|
|
|
/*
|
|
* if the attribute is inherited, forbid the renaming, unless we are
|
|
* already inside a recursive rename.
|
|
*/
|
|
if (attform->attinhcount > 0 && !recursing)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
|
|
errmsg("cannot rename inherited column \"%s\"",
|
|
oldattname)));
|
|
|
|
/* should not already exist */
|
|
/* this test is deliberately not attisdropped-aware */
|
|
if (SearchSysCacheExists(ATTNAME,
|
|
ObjectIdGetDatum(myrelid),
|
|
PointerGetDatum(newattname),
|
|
0, 0))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_DUPLICATE_COLUMN),
|
|
errmsg("column \"%s\" of relation \"%s\" already exists",
|
|
newattname, RelationGetRelationName(targetrelation))));
|
|
|
|
namestrcpy(&(attform->attname), newattname);
|
|
|
|
simple_heap_update(attrelation, &atttup->t_self, atttup);
|
|
|
|
/* keep system catalog indexes current */
|
|
CatalogUpdateIndexes(attrelation, atttup);
|
|
|
|
heap_freetuple(atttup);
|
|
|
|
/*
|
|
* Update column names of indexes that refer to the column being
|
|
* renamed.
|
|
*/
|
|
indexoidlist = RelationGetIndexList(targetrelation);
|
|
|
|
foreach(indexoidscan, indexoidlist)
|
|
{
|
|
Oid indexoid = lfirst_oid(indexoidscan);
|
|
HeapTuple indextup;
|
|
Form_pg_index indexform;
|
|
int i;
|
|
|
|
/*
|
|
* Scan through index columns to see if there's any simple index
|
|
* entries for this attribute. We ignore expressional entries.
|
|
*/
|
|
indextup = SearchSysCache(INDEXRELID,
|
|
ObjectIdGetDatum(indexoid),
|
|
0, 0, 0);
|
|
if (!HeapTupleIsValid(indextup))
|
|
elog(ERROR, "cache lookup failed for index %u", indexoid);
|
|
indexform = (Form_pg_index) GETSTRUCT(indextup);
|
|
|
|
for (i = 0; i < indexform->indnatts; i++)
|
|
{
|
|
if (attnum != indexform->indkey[i])
|
|
continue;
|
|
|
|
/*
|
|
* Found one, rename it.
|
|
*/
|
|
atttup = SearchSysCacheCopy(ATTNUM,
|
|
ObjectIdGetDatum(indexoid),
|
|
Int16GetDatum(i + 1),
|
|
0, 0);
|
|
if (!HeapTupleIsValid(atttup))
|
|
continue; /* should we raise an error? */
|
|
|
|
/*
|
|
* Update the (copied) attribute tuple.
|
|
*/
|
|
namestrcpy(&(((Form_pg_attribute) GETSTRUCT(atttup))->attname),
|
|
newattname);
|
|
|
|
simple_heap_update(attrelation, &atttup->t_self, atttup);
|
|
|
|
/* keep system catalog indexes current */
|
|
CatalogUpdateIndexes(attrelation, atttup);
|
|
|
|
heap_freetuple(atttup);
|
|
}
|
|
|
|
ReleaseSysCache(indextup);
|
|
}
|
|
|
|
list_free(indexoidlist);
|
|
|
|
heap_close(attrelation, RowExclusiveLock);
|
|
|
|
/*
|
|
* Update att name in any RI triggers associated with the relation.
|
|
*/
|
|
if (targetrelation->rd_rel->reltriggers > 0)
|
|
{
|
|
/* update tgargs column reference where att is primary key */
|
|
update_ri_trigger_args(RelationGetRelid(targetrelation),
|
|
oldattname, newattname,
|
|
false, false);
|
|
/* update tgargs column reference where att is foreign key */
|
|
update_ri_trigger_args(RelationGetRelid(targetrelation),
|
|
oldattname, newattname,
|
|
true, false);
|
|
}
|
|
|
|
relation_close(targetrelation, NoLock); /* close rel but keep lock */
|
|
}
|
|
|
|
/*
|
|
* renamerel - 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
|
|
renamerel(Oid myrelid, const char *newrelname)
|
|
{
|
|
Relation targetrelation;
|
|
Relation relrelation; /* for RELATION relation */
|
|
HeapTuple reltup;
|
|
Oid namespaceId;
|
|
char *oldrelname;
|
|
char relkind;
|
|
bool relhastriggers;
|
|
|
|
/*
|
|
* Grab an exclusive lock on the target table or index, which we will
|
|
* NOT release until end of transaction.
|
|
*/
|
|
targetrelation = relation_open(myrelid, AccessExclusiveLock);
|
|
|
|
oldrelname = pstrdup(RelationGetRelationName(targetrelation));
|
|
namespaceId = RelationGetNamespace(targetrelation);
|
|
|
|
if (!allowSystemTableMods && IsSystemRelation(targetrelation))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
|
|
errmsg("permission denied: \"%s\" is a system catalog",
|
|
RelationGetRelationName(targetrelation))));
|
|
|
|
relkind = targetrelation->rd_rel->relkind;
|
|
relhastriggers = (targetrelation->rd_rel->reltriggers > 0);
|
|
|
|
/*
|
|
* Find relation's pg_class tuple, and make sure newrelname isn't in
|
|
* use.
|
|
*/
|
|
relrelation = heap_openr(RelationRelationName, RowExclusiveLock);
|
|
|
|
reltup = SearchSysCacheCopy(RELOID,
|
|
PointerGetDatum(myrelid),
|
|
0, 0, 0);
|
|
if (!HeapTupleIsValid(reltup)) /* shouldn't happen */
|
|
elog(ERROR, "cache lookup failed for relation %u", myrelid);
|
|
|
|
if (get_relname_relid(newrelname, namespaceId) != InvalidOid)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_DUPLICATE_TABLE),
|
|
errmsg("relation \"%s\" already exists",
|
|
newrelname)));
|
|
|
|
/*
|
|
* Update pg_class tuple with new relname. (Scribbling on reltup is
|
|
* OK because it's a copy...)
|
|
*/
|
|
namestrcpy(&(((Form_pg_class) GETSTRUCT(reltup))->relname), newrelname);
|
|
|
|
simple_heap_update(relrelation, &reltup->t_self, reltup);
|
|
|
|
/* keep the system catalog indexes current */
|
|
CatalogUpdateIndexes(relrelation, reltup);
|
|
|
|
heap_freetuple(reltup);
|
|
heap_close(relrelation, RowExclusiveLock);
|
|
|
|
/*
|
|
* Also rename the associated type, if any.
|
|
*/
|
|
if (relkind != RELKIND_INDEX)
|
|
TypeRename(oldrelname, namespaceId, newrelname);
|
|
|
|
/*
|
|
* Update rel name in any RI triggers associated with the relation.
|
|
*/
|
|
if (relhastriggers)
|
|
{
|
|
/* update tgargs where relname is primary key */
|
|
update_ri_trigger_args(myrelid,
|
|
oldrelname,
|
|
newrelname,
|
|
false, true);
|
|
/* update tgargs where relname is foreign key */
|
|
update_ri_trigger_args(myrelid,
|
|
oldrelname,
|
|
newrelname,
|
|
true, true);
|
|
}
|
|
|
|
/*
|
|
* Close rel, but keep exclusive lock!
|
|
*/
|
|
relation_close(targetrelation, NoLock);
|
|
}
|
|
|
|
|
|
/*
|
|
* Given a trigger function OID, determine whether it is an RI trigger,
|
|
* and if so whether it is attached to PK or FK relation.
|
|
*
|
|
* XXX this probably doesn't belong here; should be exported by
|
|
* ri_triggers.c
|
|
*/
|
|
static int
|
|
ri_trigger_type(Oid tgfoid)
|
|
{
|
|
switch (tgfoid)
|
|
{
|
|
case F_RI_FKEY_CASCADE_DEL:
|
|
case F_RI_FKEY_CASCADE_UPD:
|
|
case F_RI_FKEY_RESTRICT_DEL:
|
|
case F_RI_FKEY_RESTRICT_UPD:
|
|
case F_RI_FKEY_SETNULL_DEL:
|
|
case F_RI_FKEY_SETNULL_UPD:
|
|
case F_RI_FKEY_SETDEFAULT_DEL:
|
|
case F_RI_FKEY_SETDEFAULT_UPD:
|
|
case F_RI_FKEY_NOACTION_DEL:
|
|
case F_RI_FKEY_NOACTION_UPD:
|
|
return RI_TRIGGER_PK;
|
|
|
|
case F_RI_FKEY_CHECK_INS:
|
|
case F_RI_FKEY_CHECK_UPD:
|
|
return RI_TRIGGER_FK;
|
|
}
|
|
|
|
return RI_TRIGGER_NONE;
|
|
}
|
|
|
|
/*
|
|
* Scan pg_trigger for RI triggers that are on the specified relation
|
|
* (if fk_scan is false) or have it as the tgconstrrel (if fk_scan
|
|
* is true). Update RI trigger args fields matching oldname to contain
|
|
* newname instead. If update_relname is true, examine the relname
|
|
* fields; otherwise examine the attname fields.
|
|
*/
|
|
static void
|
|
update_ri_trigger_args(Oid relid,
|
|
const char *oldname,
|
|
const char *newname,
|
|
bool fk_scan,
|
|
bool update_relname)
|
|
{
|
|
Relation tgrel;
|
|
ScanKeyData skey[1];
|
|
SysScanDesc trigscan;
|
|
HeapTuple tuple;
|
|
Datum values[Natts_pg_trigger];
|
|
char nulls[Natts_pg_trigger];
|
|
char replaces[Natts_pg_trigger];
|
|
|
|
tgrel = heap_openr(TriggerRelationName, RowExclusiveLock);
|
|
if (fk_scan)
|
|
{
|
|
ScanKeyInit(&skey[0],
|
|
Anum_pg_trigger_tgconstrrelid,
|
|
BTEqualStrategyNumber, F_OIDEQ,
|
|
ObjectIdGetDatum(relid));
|
|
trigscan = systable_beginscan(tgrel, TriggerConstrRelidIndex,
|
|
true, SnapshotNow,
|
|
1, skey);
|
|
}
|
|
else
|
|
{
|
|
ScanKeyInit(&skey[0],
|
|
Anum_pg_trigger_tgrelid,
|
|
BTEqualStrategyNumber, F_OIDEQ,
|
|
ObjectIdGetDatum(relid));
|
|
trigscan = systable_beginscan(tgrel, TriggerRelidNameIndex,
|
|
true, SnapshotNow,
|
|
1, skey);
|
|
}
|
|
|
|
while ((tuple = systable_getnext(trigscan)) != NULL)
|
|
{
|
|
Form_pg_trigger pg_trigger = (Form_pg_trigger) GETSTRUCT(tuple);
|
|
bytea *val;
|
|
bytea *newtgargs;
|
|
bool isnull;
|
|
int tg_type;
|
|
bool examine_pk;
|
|
bool changed;
|
|
int tgnargs;
|
|
int i;
|
|
int newlen;
|
|
const char *arga[RI_MAX_ARGUMENTS];
|
|
const char *argp;
|
|
|
|
tg_type = ri_trigger_type(pg_trigger->tgfoid);
|
|
if (tg_type == RI_TRIGGER_NONE)
|
|
{
|
|
/* Not an RI trigger, forget it */
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
* It is an RI trigger, so parse the tgargs bytea.
|
|
*
|
|
* NB: we assume the field will never be compressed or moved out of
|
|
* line; so does trigger.c ...
|
|
*/
|
|
tgnargs = pg_trigger->tgnargs;
|
|
val = (bytea *) fastgetattr(tuple,
|
|
Anum_pg_trigger_tgargs,
|
|
tgrel->rd_att, &isnull);
|
|
if (isnull || tgnargs < RI_FIRST_ATTNAME_ARGNO ||
|
|
tgnargs > RI_MAX_ARGUMENTS)
|
|
{
|
|
/* This probably shouldn't happen, but ignore busted triggers */
|
|
continue;
|
|
}
|
|
argp = (const char *) VARDATA(val);
|
|
for (i = 0; i < tgnargs; i++)
|
|
{
|
|
arga[i] = argp;
|
|
argp += strlen(argp) + 1;
|
|
}
|
|
|
|
/*
|
|
* Figure out which item(s) to look at. If the trigger is
|
|
* primary-key type and attached to my rel, I should look at the
|
|
* PK fields; if it is foreign-key type and attached to my rel, I
|
|
* should look at the FK fields. But the opposite rule holds when
|
|
* examining triggers found by tgconstrrel search.
|
|
*/
|
|
examine_pk = (tg_type == RI_TRIGGER_PK) == (!fk_scan);
|
|
|
|
changed = false;
|
|
if (update_relname)
|
|
{
|
|
/* Change the relname if needed */
|
|
i = examine_pk ? RI_PK_RELNAME_ARGNO : RI_FK_RELNAME_ARGNO;
|
|
if (strcmp(arga[i], oldname) == 0)
|
|
{
|
|
arga[i] = newname;
|
|
changed = true;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
/* Change attname(s) if needed */
|
|
i = examine_pk ? RI_FIRST_ATTNAME_ARGNO + RI_KEYPAIR_PK_IDX :
|
|
RI_FIRST_ATTNAME_ARGNO + RI_KEYPAIR_FK_IDX;
|
|
for (; i < tgnargs; i += 2)
|
|
{
|
|
if (strcmp(arga[i], oldname) == 0)
|
|
{
|
|
arga[i] = newname;
|
|
changed = true;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (!changed)
|
|
{
|
|
/* Don't need to update this tuple */
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
* Construct modified tgargs bytea.
|
|
*/
|
|
newlen = VARHDRSZ;
|
|
for (i = 0; i < tgnargs; i++)
|
|
newlen += strlen(arga[i]) + 1;
|
|
newtgargs = (bytea *) palloc(newlen);
|
|
VARATT_SIZEP(newtgargs) = newlen;
|
|
newlen = VARHDRSZ;
|
|
for (i = 0; i < tgnargs; i++)
|
|
{
|
|
strcpy(((char *) newtgargs) + newlen, arga[i]);
|
|
newlen += strlen(arga[i]) + 1;
|
|
}
|
|
|
|
/*
|
|
* Build modified tuple.
|
|
*/
|
|
for (i = 0; i < Natts_pg_trigger; i++)
|
|
{
|
|
values[i] = (Datum) 0;
|
|
replaces[i] = ' ';
|
|
nulls[i] = ' ';
|
|
}
|
|
values[Anum_pg_trigger_tgargs - 1] = PointerGetDatum(newtgargs);
|
|
replaces[Anum_pg_trigger_tgargs - 1] = 'r';
|
|
|
|
tuple = heap_modifytuple(tuple, tgrel, values, nulls, replaces);
|
|
|
|
/*
|
|
* Update pg_trigger and its indexes
|
|
*/
|
|
simple_heap_update(tgrel, &tuple->t_self, tuple);
|
|
|
|
CatalogUpdateIndexes(tgrel, tuple);
|
|
|
|
/*
|
|
* Invalidate trigger's relation's relcache entry so that other
|
|
* backends (and this one too!) are sent SI message to make them
|
|
* rebuild relcache entries. (Ideally this should happen
|
|
* automatically...)
|
|
*
|
|
* We can skip this for triggers on relid itself, since that
|
|
* relcache flush will happen anyway due to the table or column
|
|
* rename. We just need to catch the far ends of RI relationships.
|
|
*/
|
|
pg_trigger = (Form_pg_trigger) GETSTRUCT(tuple);
|
|
if (pg_trigger->tgrelid != relid)
|
|
CacheInvalidateRelcacheByRelid(pg_trigger->tgrelid);
|
|
|
|
/* free up our scratch memory */
|
|
pfree(newtgargs);
|
|
heap_freetuple(tuple);
|
|
}
|
|
|
|
systable_endscan(trigscan);
|
|
|
|
heap_close(tgrel, RowExclusiveLock);
|
|
|
|
/*
|
|
* Increment cmd counter to make updates visible; this is needed in
|
|
* case the same tuple has to be updated again by next pass (can
|
|
* happen in case of a self-referential FK relationship).
|
|
*/
|
|
CommandCounterIncrement();
|
|
}
|
|
|
|
/*
|
|
* 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
|
|
* 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.
|
|
*
|
|
* 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 do no explicit recursion, since phase 1 already did it).
|
|
* Certain subcommands need to be performed before others to avoid
|
|
* unnecessary conflicts; for example, DROP COLUMN should come before
|
|
* 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.
|
|
*/
|
|
void
|
|
AlterTable(AlterTableStmt *stmt)
|
|
{
|
|
ATController(relation_openrv(stmt->relation, AccessExclusiveLock),
|
|
stmt->cmds,
|
|
interpretInhOption(stmt->relation->inhOpt));
|
|
}
|
|
|
|
/*
|
|
* AlterTableInternal
|
|
*
|
|
* ALTER TABLE with target specified by OID
|
|
*/
|
|
void
|
|
AlterTableInternal(Oid relid, List *cmds, bool recurse)
|
|
{
|
|
ATController(relation_open(relid, AccessExclusiveLock),
|
|
cmds,
|
|
recurse);
|
|
}
|
|
|
|
static void
|
|
ATController(Relation rel, List *cmds, bool recurse)
|
|
{
|
|
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);
|
|
}
|
|
|
|
/* Close the relation, but keep lock until commit */
|
|
relation_close(rel, NoLock);
|
|
|
|
/* Phase 2: update system catalogs */
|
|
ATRewriteCatalogs(&wqueue);
|
|
|
|
/* Phase 3: scan/rewrite tables as needed */
|
|
ATRewriteTables(&wqueue);
|
|
}
|
|
|
|
/*
|
|
* ATPrepCmd
|
|
*
|
|
* Traffic cop for ALTER TABLE Phase 1 operations, including simple
|
|
* recursion and permission checks.
|
|
*
|
|
* Caller must have acquired AccessExclusiveLock on relation already.
|
|
* This lock should be held until commit.
|
|
*/
|
|
static void
|
|
ATPrepCmd(List **wqueue, Relation rel, AlterTableCmd *cmd,
|
|
bool recurse, bool recursing)
|
|
{
|
|
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
|
|
* transformations (for example, the same column may have different
|
|
* column numbers in different children).
|
|
*/
|
|
cmd = copyObject(cmd);
|
|
|
|
/*
|
|
* 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, false);
|
|
/* Performs own recursion */
|
|
ATPrepAddColumn(wqueue, rel, recurse, cmd);
|
|
pass = AT_PASS_ADD_COL;
|
|
break;
|
|
case AT_ColumnDefault: /* ALTER COLUMN DEFAULT */
|
|
/*
|
|
* 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, true);
|
|
ATSimpleRecursion(wqueue, rel, cmd, recurse);
|
|
/* No command-specific prep needed */
|
|
pass = AT_PASS_ADD_CONSTR;
|
|
break;
|
|
case AT_DropNotNull: /* ALTER COLUMN DROP NOT NULL */
|
|
ATSimplePermissions(rel, false);
|
|
ATSimpleRecursion(wqueue, rel, cmd, recurse);
|
|
/* No command-specific prep needed */
|
|
pass = AT_PASS_DROP;
|
|
break;
|
|
case AT_SetNotNull: /* ALTER COLUMN SET NOT NULL */
|
|
ATSimplePermissions(rel, false);
|
|
ATSimpleRecursion(wqueue, rel, cmd, recurse);
|
|
/* No command-specific prep needed */
|
|
pass = AT_PASS_ADD_CONSTR;
|
|
break;
|
|
case AT_SetStatistics: /* ALTER COLUMN STATISTICS */
|
|
ATSimpleRecursion(wqueue, rel, cmd, recurse);
|
|
/* Performs own permission checks */
|
|
ATPrepSetStatistics(rel, cmd->name, cmd->def);
|
|
pass = AT_PASS_COL_ATTRS;
|
|
break;
|
|
case AT_SetStorage: /* ALTER COLUMN STORAGE */
|
|
ATSimplePermissions(rel, false);
|
|
ATSimpleRecursion(wqueue, rel, cmd, recurse);
|
|
/* No command-specific prep needed */
|
|
pass = AT_PASS_COL_ATTRS;
|
|
break;
|
|
case AT_DropColumn: /* DROP COLUMN */
|
|
ATSimplePermissions(rel, false);
|
|
/* Recursion occurs during execution phase */
|
|
/* No command-specific prep needed except saving recurse flag */
|
|
if (recurse)
|
|
cmd->subtype = AT_DropColumnRecurse;
|
|
pass = AT_PASS_DROP;
|
|
break;
|
|
case AT_AddIndex: /* ADD INDEX */
|
|
ATSimplePermissions(rel, false);
|
|
/* This command never recurses */
|
|
/* No command-specific prep needed */
|
|
pass = AT_PASS_ADD_INDEX;
|
|
break;
|
|
case AT_AddConstraint: /* ADD CONSTRAINT */
|
|
ATSimplePermissions(rel, false);
|
|
/*
|
|
* Currently we recurse only for CHECK constraints, never for
|
|
* foreign-key constraints. UNIQUE/PKEY constraints won't be
|
|
* seen here.
|
|
*/
|
|
if (IsA(cmd->def, Constraint))
|
|
ATSimpleRecursion(wqueue, rel, cmd, recurse);
|
|
/* No command-specific prep needed */
|
|
pass = AT_PASS_ADD_CONSTR;
|
|
break;
|
|
case AT_DropConstraint: /* DROP CONSTRAINT */
|
|
ATSimplePermissions(rel, false);
|
|
/* Performs own recursion */
|
|
ATPrepDropConstraint(wqueue, rel, recurse, cmd);
|
|
pass = AT_PASS_DROP;
|
|
break;
|
|
case AT_DropConstraintQuietly: /* DROP CONSTRAINT for child */
|
|
ATSimplePermissions(rel, false);
|
|
ATSimpleRecursion(wqueue, rel, cmd, recurse);
|
|
/* No command-specific prep needed */
|
|
pass = AT_PASS_DROP;
|
|
break;
|
|
case AT_AlterColumnType: /* ALTER COLUMN TYPE */
|
|
ATSimplePermissions(rel, false);
|
|
/* Performs own recursion */
|
|
ATPrepAlterColumnType(wqueue, tab, rel, recurse, recursing, cmd);
|
|
pass = AT_PASS_ALTER_TYPE;
|
|
break;
|
|
case AT_ToastTable: /* CREATE TOAST TABLE */
|
|
ATSimplePermissions(rel, false);
|
|
/* 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;
|
|
case AT_ClusterOn: /* CLUSTER ON */
|
|
case AT_DropCluster: /* SET WITHOUT CLUSTER */
|
|
ATSimplePermissions(rel, false);
|
|
/* These commands never recurse */
|
|
/* No command-specific prep needed */
|
|
pass = AT_PASS_MISC;
|
|
break;
|
|
case AT_DropOids: /* SET WITHOUT OIDS */
|
|
ATSimplePermissions(rel, false);
|
|
/* 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);
|
|
}
|
|
pass = AT_PASS_DROP;
|
|
break;
|
|
case AT_SetTableSpace: /* SET TABLESPACE */
|
|
/* This command never recurses */
|
|
ATPrepSetTableSpace(tab, rel, cmd->name);
|
|
pass = AT_PASS_MISC; /* doesn't actually matter */
|
|
break;
|
|
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
|
|
*
|
|
* 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)
|
|
{
|
|
int pass;
|
|
ListCell *ltab;
|
|
|
|
/*
|
|
* 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;
|
|
|
|
/* Exclusive lock was obtained by phase 1, needn't get it again */
|
|
rel = relation_open(tab->relid, NoLock);
|
|
|
|
foreach(lcmd, subcmds)
|
|
{
|
|
ATExecCmd(tab, rel, (AlterTableCmd *) lfirst(lcmd));
|
|
}
|
|
|
|
/*
|
|
* 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);
|
|
|
|
relation_close(rel, NoLock);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Do an implicit CREATE TOAST TABLE if we executed any subcommands
|
|
* that might have added a column or changed column storage.
|
|
*/
|
|
foreach(ltab, *wqueue)
|
|
{
|
|
AlteredTableInfo *tab = (AlteredTableInfo *) lfirst(ltab);
|
|
|
|
if (tab->relkind == RELKIND_RELATION &&
|
|
(tab->subcmds[AT_PASS_ADD_COL] ||
|
|
tab->subcmds[AT_PASS_ALTER_TYPE] ||
|
|
tab->subcmds[AT_PASS_COL_ATTRS]))
|
|
{
|
|
AlterTableCreateToastTable(tab->relid, true);
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* ATExecCmd: dispatch a subcommand to appropriate execution routine
|
|
*/
|
|
static void
|
|
ATExecCmd(AlteredTableInfo *tab, Relation rel, AlterTableCmd *cmd)
|
|
{
|
|
switch (cmd->subtype)
|
|
{
|
|
case AT_AddColumn: /* ADD COLUMN */
|
|
ATExecAddColumn(tab, rel, (ColumnDef *) cmd->def);
|
|
break;
|
|
case AT_ColumnDefault: /* ALTER COLUMN DEFAULT */
|
|
ATExecColumnDefault(rel, cmd->name, cmd->def);
|
|
break;
|
|
case AT_DropNotNull: /* ALTER COLUMN DROP NOT NULL */
|
|
ATExecDropNotNull(rel, cmd->name);
|
|
break;
|
|
case AT_SetNotNull: /* ALTER COLUMN SET NOT NULL */
|
|
ATExecSetNotNull(tab, rel, cmd->name);
|
|
break;
|
|
case AT_SetStatistics: /* ALTER COLUMN STATISTICS */
|
|
ATExecSetStatistics(rel, cmd->name, cmd->def);
|
|
break;
|
|
case AT_SetStorage: /* ALTER COLUMN STORAGE */
|
|
ATExecSetStorage(rel, cmd->name, cmd->def);
|
|
break;
|
|
case AT_DropColumn: /* DROP COLUMN */
|
|
ATExecDropColumn(rel, cmd->name, cmd->behavior, false, false);
|
|
break;
|
|
case AT_DropColumnRecurse: /* DROP COLUMN with recursion */
|
|
ATExecDropColumn(rel, cmd->name, cmd->behavior, true, false);
|
|
break;
|
|
case AT_AddIndex: /* ADD INDEX */
|
|
ATExecAddIndex(tab, rel, (IndexStmt *) cmd->def, false);
|
|
break;
|
|
case AT_ReAddIndex: /* ADD INDEX */
|
|
ATExecAddIndex(tab, rel, (IndexStmt *) cmd->def, true);
|
|
break;
|
|
case AT_AddConstraint: /* ADD CONSTRAINT */
|
|
ATExecAddConstraint(tab, rel, cmd->def);
|
|
break;
|
|
case AT_DropConstraint: /* DROP CONSTRAINT */
|
|
ATExecDropConstraint(rel, cmd->name, cmd->behavior, false);
|
|
break;
|
|
case AT_DropConstraintQuietly: /* DROP CONSTRAINT for child */
|
|
ATExecDropConstraint(rel, cmd->name, cmd->behavior, true);
|
|
break;
|
|
case AT_AlterColumnType: /* ALTER COLUMN TYPE */
|
|
ATExecAlterColumnType(tab, rel, cmd->name, (TypeName *) cmd->def);
|
|
break;
|
|
case AT_ToastTable: /* CREATE TOAST TABLE */
|
|
AlterTableCreateToastTable(RelationGetRelid(rel), false);
|
|
break;
|
|
case AT_ChangeOwner: /* ALTER OWNER */
|
|
/* get_usesysid raises an error if no such user */
|
|
ATExecChangeOwner(RelationGetRelid(rel), get_usesysid(cmd->name));
|
|
break;
|
|
case AT_ClusterOn: /* CLUSTER ON */
|
|
ATExecClusterOn(rel, cmd->name);
|
|
break;
|
|
case AT_DropCluster: /* SET WITHOUT CLUSTER */
|
|
ATExecDropCluster(rel);
|
|
break;
|
|
case AT_DropOids: /* SET WITHOUT OIDS */
|
|
/*
|
|
* Nothing to do here; we'll have generated a DropColumn subcommand
|
|
* to do the real work
|
|
*/
|
|
break;
|
|
case AT_SetTableSpace: /* SET TABLESPACE */
|
|
/*
|
|
* Nothing to do here; Phase 3 does the work
|
|
*/
|
|
break;
|
|
default: /* oops */
|
|
elog(ERROR, "unrecognized alter table type: %d",
|
|
(int) cmd->subtype);
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* 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)
|
|
{
|
|
ListCell *ltab;
|
|
|
|
/* Go through each table that needs to be checked or rewritten */
|
|
foreach(ltab, *wqueue)
|
|
{
|
|
AlteredTableInfo *tab = (AlteredTableInfo *) lfirst(ltab);
|
|
|
|
/*
|
|
* We only need to rewrite the table if at least one column needs
|
|
* to be recomputed.
|
|
*/
|
|
if (tab->newvals != NIL)
|
|
{
|
|
/* Build a temporary relation and copy data */
|
|
Oid OIDNewHeap;
|
|
char NewHeapName[NAMEDATALEN];
|
|
Oid NewTableSpace;
|
|
Relation OldHeap;
|
|
ObjectAddress object;
|
|
|
|
OldHeap = heap_open(tab->relid, NoLock);
|
|
|
|
/*
|
|
* We can never allow rewriting of shared or nailed-in-cache
|
|
* relations, because we can't support changing their relfilenode
|
|
* values.
|
|
*/
|
|
if (OldHeap->rd_rel->relisshared || OldHeap->rd_isnailed)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
errmsg("cannot rewrite system relation \"%s\"",
|
|
RelationGetRelationName(OldHeap))));
|
|
|
|
/*
|
|
* Don't allow rewrite on temp tables of other backends ... their
|
|
* local buffer manager is not going to cope.
|
|
*/
|
|
if (isOtherTempNamespace(RelationGetNamespace(OldHeap)))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
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 the new heap, using a temporary name in the same
|
|
* namespace as the existing table. NOTE: there is some risk of
|
|
* collision with user relnames. Working around this seems more
|
|
* trouble than it's worth; in particular, we can't create the new
|
|
* heap in a different namespace from the old, or we will have
|
|
* problems with the TEMP status of temp tables.
|
|
*/
|
|
snprintf(NewHeapName, sizeof(NewHeapName),
|
|
"pg_temp_%u", tab->relid);
|
|
|
|
OIDNewHeap = make_new_heap(tab->relid, NewHeapName, 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);
|
|
|
|
/* Swap the physical files of the old and new heaps. */
|
|
swap_relation_files(tab->relid, OIDNewHeap);
|
|
|
|
CommandCounterIncrement();
|
|
|
|
/* Destroy new heap with old filenode */
|
|
object.classId = RelOid_pg_class;
|
|
object.objectId = OIDNewHeap;
|
|
object.objectSubId = 0;
|
|
|
|
/*
|
|
* The new relation is local to our transaction and we know nothing
|
|
* depends on it, so DROP_RESTRICT should be OK.
|
|
*/
|
|
performDeletion(&object, DROP_RESTRICT);
|
|
/* performDeletion does CommandCounterIncrement at end */
|
|
|
|
/*
|
|
* Rebuild each index on the relation (but not the toast table,
|
|
* which is all-new anyway). We do not need
|
|
* CommandCounterIncrement() because reindex_relation does it.
|
|
*/
|
|
reindex_relation(tab->relid, false);
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* Test the current data within the table against new constraints
|
|
* generated by ALTER TABLE commands, but don't rebuild data.
|
|
*/
|
|
if (tab->constraints != NIL)
|
|
ATRewriteTable(tab, InvalidOid);
|
|
/*
|
|
* 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);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Foreign key constraints are checked in a final pass, since
|
|
* (a) it's 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)
|
|
{
|
|
AlteredTableInfo *tab = (AlteredTableInfo *) lfirst(ltab);
|
|
Relation rel = NULL;
|
|
ListCell *lcon;
|
|
|
|
foreach(lcon, tab->constraints)
|
|
{
|
|
NewConstraint *con = lfirst(lcon);
|
|
|
|
if (con->contype == CONSTR_FOREIGN)
|
|
{
|
|
FkConstraint *fkconstraint = (FkConstraint *) 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, rel, refrel);
|
|
|
|
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)
|
|
{
|
|
Relation oldrel;
|
|
Relation newrel;
|
|
TupleDesc oldTupDesc;
|
|
TupleDesc newTupDesc;
|
|
bool needscan = false;
|
|
int i;
|
|
ListCell *l;
|
|
EState *estate;
|
|
|
|
/*
|
|
* Open the relation(s). We have surely already locked the existing
|
|
* table.
|
|
*/
|
|
oldrel = heap_open(tab->relid, NoLock);
|
|
oldTupDesc = tab->oldDesc;
|
|
newTupDesc = RelationGetDescr(oldrel); /* includes all mods */
|
|
|
|
if (OidIsValid(OIDNewHeap))
|
|
newrel = heap_open(OIDNewHeap, AccessExclusiveLock);
|
|
else
|
|
newrel = NULL;
|
|
|
|
/*
|
|
* If we need to rewrite the table, the operation has to be propagated
|
|
* to tables that use this table's rowtype as a column type.
|
|
*
|
|
* (Eventually this will probably become true for scans as well, but
|
|
* at the moment a composite type does not enforce any constraints,
|
|
* so it's not necessary/appropriate to enforce them just during ALTER.)
|
|
*/
|
|
if (newrel)
|
|
find_composite_type_dependencies(oldrel->rd_rel->reltype,
|
|
RelationGetRelationName(oldrel));
|
|
|
|
/*
|
|
* 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;
|
|
case CONSTR_NOTNULL:
|
|
needscan = true;
|
|
break;
|
|
default:
|
|
elog(ERROR, "unrecognized constraint type: %d",
|
|
(int) con->contype);
|
|
}
|
|
}
|
|
|
|
foreach(l, tab->newvals)
|
|
{
|
|
NewColumnValue *ex = lfirst(l);
|
|
|
|
needscan = true;
|
|
|
|
ex->exprstate = ExecPrepareExpr((Expr *) ex->expr, estate);
|
|
}
|
|
|
|
if (needscan)
|
|
{
|
|
ExprContext *econtext;
|
|
Datum *values;
|
|
char *nulls;
|
|
TupleTableSlot *oldslot;
|
|
TupleTableSlot *newslot;
|
|
HeapScanDesc scan;
|
|
HeapTuple tuple;
|
|
|
|
econtext = GetPerTupleExprContext(estate);
|
|
|
|
/*
|
|
* 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 = MakeTupleTableSlot();
|
|
ExecSetSlotDescriptor(oldslot, oldTupDesc, false);
|
|
newslot = MakeTupleTableSlot();
|
|
ExecSetSlotDescriptor(newslot, newTupDesc, false);
|
|
|
|
/* Preallocate values/nulls arrays */
|
|
i = Max(newTupDesc->natts, oldTupDesc->natts);
|
|
values = (Datum *) palloc(i * sizeof(Datum));
|
|
nulls = (char *) palloc(i * sizeof(char));
|
|
memset(values, 0, i * sizeof(Datum));
|
|
memset(nulls, 'n', i * sizeof(char));
|
|
|
|
/*
|
|
* Scan through the rows, generating a new row if needed and then
|
|
* checking all the constraints.
|
|
*/
|
|
scan = heap_beginscan(oldrel, SnapshotNow, 0, NULL);
|
|
|
|
while ((tuple = heap_getnext(scan, ForwardScanDirection)) != NULL)
|
|
{
|
|
if (newrel)
|
|
{
|
|
/*
|
|
* Extract data from old tuple. We can force to null any
|
|
* columns that are deleted according to the new tuple.
|
|
*/
|
|
int natts = newTupDesc->natts;
|
|
|
|
heap_deformtuple(tuple, oldTupDesc, values, nulls);
|
|
|
|
for (i = 0; i < natts; i++)
|
|
{
|
|
if (newTupDesc->attrs[i]->attisdropped)
|
|
nulls[i] = 'n';
|
|
}
|
|
|
|
/*
|
|
* 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)
|
|
{
|
|
NewColumnValue *ex = lfirst(l);
|
|
bool isNull;
|
|
|
|
values[ex->attnum - 1] = ExecEvalExpr(ex->exprstate,
|
|
econtext,
|
|
&isNull,
|
|
NULL);
|
|
if (isNull)
|
|
nulls[ex->attnum - 1] = 'n';
|
|
else
|
|
nulls[ex->attnum - 1] = ' ';
|
|
}
|
|
|
|
tuple = heap_formtuple(newTupDesc, values, nulls);
|
|
}
|
|
|
|
/* Now check any constraints on the possibly-changed tuple */
|
|
ExecStoreTuple(tuple, newslot, InvalidBuffer, false);
|
|
econtext->ecxt_scantuple = newslot;
|
|
|
|
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)));
|
|
break;
|
|
case CONSTR_NOTNULL:
|
|
{
|
|
Datum d;
|
|
bool isnull;
|
|
|
|
d = heap_getattr(tuple, con->attnum, newTupDesc,
|
|
&isnull);
|
|
if (isnull)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_NOT_NULL_VIOLATION),
|
|
errmsg("column \"%s\" contains null values",
|
|
get_attname(tab->relid,
|
|
con->attnum))));
|
|
}
|
|
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)
|
|
{
|
|
simple_heap_insert(newrel, tuple);
|
|
|
|
heap_freetuple(tuple);
|
|
}
|
|
|
|
ResetExprContext(econtext);
|
|
|
|
CHECK_FOR_INTERRUPTS();
|
|
}
|
|
|
|
heap_endscan(scan);
|
|
}
|
|
|
|
FreeExecutorState(estate);
|
|
|
|
heap_close(oldrel, NoLock);
|
|
if (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, bool allowView)
|
|
{
|
|
if (rel->rd_rel->relkind != RELKIND_RELATION)
|
|
{
|
|
if (allowView)
|
|
{
|
|
if (rel->rd_rel->relkind != RELKIND_VIEW)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
|
|
errmsg("\"%s\" is not a table or view",
|
|
RelationGetRelationName(rel))));
|
|
}
|
|
else
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
|
|
errmsg("\"%s\" is not a table",
|
|
RelationGetRelationName(rel))));
|
|
}
|
|
|
|
/* 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))));
|
|
}
|
|
|
|
/*
|
|
* 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)
|
|
{
|
|
/*
|
|
* 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;
|
|
|
|
/* this routine is actually in the planner */
|
|
children = find_all_inheritors(relid);
|
|
|
|
/*
|
|
* 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;
|
|
childrel = relation_open(childrelid, AccessExclusiveLock);
|
|
ATPrepCmd(wqueue, childrel, cmd, false, true);
|
|
relation_close(childrel, NoLock);
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* ATOneLevelRecursion
|
|
*
|
|
* Here, we visit only direct inheritance children. It is expected that
|
|
* the command's prep routine will recurse again to find indirect children.
|
|
* When using this technique, a multiply-inheriting child will be visited
|
|
* multiple times.
|
|
*/
|
|
static void
|
|
ATOneLevelRecursion(List **wqueue, Relation rel,
|
|
AlterTableCmd *cmd)
|
|
{
|
|
Oid relid = RelationGetRelid(rel);
|
|
ListCell *child;
|
|
List *children;
|
|
|
|
/* this routine is actually in the planner */
|
|
children = find_inheritance_children(relid);
|
|
|
|
foreach(child, children)
|
|
{
|
|
Oid childrelid = lfirst_oid(child);
|
|
Relation childrel;
|
|
|
|
childrel = relation_open(childrelid, AccessExclusiveLock);
|
|
ATPrepCmd(wqueue, childrel, cmd, true, true);
|
|
relation_close(childrel, NoLock);
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
* find_composite_type_dependencies
|
|
*
|
|
* Check to see if a table's rowtype 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.
|
|
*
|
|
* We assume that functions and views depending on the type are not reasons
|
|
* to reject the ALTER. (How safe is this really?)
|
|
*/
|
|
static void
|
|
find_composite_type_dependencies(Oid typeOid, const char *origTblName)
|
|
{
|
|
Relation depRel;
|
|
ScanKeyData key[2];
|
|
SysScanDesc depScan;
|
|
HeapTuple depTup;
|
|
|
|
/*
|
|
* We scan pg_depend to find those things that depend on the rowtype.
|
|
* (We assume we can ignore refobjsubid for a rowtype.)
|
|
*/
|
|
depRel = relation_openr(DependRelationName, AccessShareLock);
|
|
|
|
ScanKeyInit(&key[0],
|
|
Anum_pg_depend_refclassid,
|
|
BTEqualStrategyNumber, F_OIDEQ,
|
|
ObjectIdGetDatum(RelOid_pg_type));
|
|
ScanKeyInit(&key[1],
|
|
Anum_pg_depend_refobjid,
|
|
BTEqualStrategyNumber, F_OIDEQ,
|
|
ObjectIdGetDatum(typeOid));
|
|
|
|
depScan = systable_beginscan(depRel, DependReferenceIndex, 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 != RelOid_pg_class ||
|
|
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)
|
|
{
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
errmsg("cannot alter table \"%s\" because column \"%s\".\"%s\" uses its rowtype",
|
|
origTblName,
|
|
RelationGetRelationName(rel),
|
|
NameStr(att->attname))));
|
|
}
|
|
else if (OidIsValid(rel->rd_rel->reltype))
|
|
{
|
|
/*
|
|
* 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,
|
|
origTblName);
|
|
}
|
|
|
|
relation_close(rel, AccessShareLock);
|
|
}
|
|
|
|
systable_endscan(depScan);
|
|
|
|
relation_close(depRel, AccessShareLock);
|
|
}
|
|
|
|
|
|
/*
|
|
* 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 analyze.c and added as independent
|
|
* AlterTableCmd's.
|
|
*/
|
|
static void
|
|
ATPrepAddColumn(List **wqueue, Relation rel, bool recurse,
|
|
AlterTableCmd *cmd)
|
|
{
|
|
/*
|
|
* Recurse to add the column to child classes, if requested.
|
|
*
|
|
* We must recurse one level at a time, so that multiply-inheriting
|
|
* children are visited the right number of times and end up with the
|
|
* right attinhcount.
|
|
*/
|
|
if (recurse)
|
|
{
|
|
AlterTableCmd *childCmd = copyObject(cmd);
|
|
ColumnDef *colDefChild = (ColumnDef *) childCmd->def;
|
|
|
|
/* Child should see column as singly inherited */
|
|
colDefChild->inhcount = 1;
|
|
colDefChild->is_local = false;
|
|
/* and don't make a support dependency on the child */
|
|
colDefChild->support = NULL;
|
|
|
|
ATOneLevelRecursion(wqueue, rel, childCmd);
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* 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 (find_inheritance_children(RelationGetRelid(rel)) != NIL)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
|
|
errmsg("column must be added to child tables too")));
|
|
}
|
|
}
|
|
|
|
static void
|
|
ATExecAddColumn(AlteredTableInfo *tab, Relation rel,
|
|
ColumnDef *colDef)
|
|
{
|
|
Oid myrelid = RelationGetRelid(rel);
|
|
Relation pgclass,
|
|
attrdesc;
|
|
HeapTuple reltup;
|
|
HeapTuple attributeTuple;
|
|
Form_pg_attribute attribute;
|
|
FormData_pg_attribute attributeD;
|
|
int i;
|
|
int minattnum,
|
|
maxatts;
|
|
HeapTuple typeTuple;
|
|
Form_pg_type tform;
|
|
Expr *defval;
|
|
|
|
attrdesc = heap_openr(AttributeRelationName, RowExclusiveLock);
|
|
|
|
/*
|
|
* Are we adding the column to a recursion child? If so, check whether
|
|
* to merge with an existing definition for the column.
|
|
*/
|
|
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);
|
|
|
|
/* Okay if child matches by type */
|
|
if (typenameTypeId(colDef->typename) != childatt->atttypid ||
|
|
colDef->typename->typmod != childatt->atttypmod)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_DATATYPE_MISMATCH),
|
|
errmsg("child table \"%s\" has different type for column \"%s\"",
|
|
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,
|
|
(errmsg("merging definition of column \"%s\" for child \"%s\"",
|
|
colDef->colname, RelationGetRelationName(rel))));
|
|
|
|
heap_close(attrdesc, RowExclusiveLock);
|
|
return;
|
|
}
|
|
}
|
|
|
|
pgclass = heap_openr(RelationRelationName, RowExclusiveLock);
|
|
|
|
reltup = SearchSysCacheCopy(RELOID,
|
|
ObjectIdGetDatum(myrelid),
|
|
0, 0, 0);
|
|
if (!HeapTupleIsValid(reltup))
|
|
elog(ERROR, "cache lookup failed for relation %u", myrelid);
|
|
|
|
/*
|
|
* 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.
|
|
*/
|
|
if (SearchSysCacheExists(ATTNAME,
|
|
ObjectIdGetDatum(myrelid),
|
|
PointerGetDatum(colDef->colname),
|
|
0, 0))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_DUPLICATE_COLUMN),
|
|
errmsg("column \"%s\" of relation \"%s\" already exists",
|
|
colDef->colname, RelationGetRelationName(rel))));
|
|
|
|
minattnum = ((Form_pg_class) GETSTRUCT(reltup))->relnatts;
|
|
maxatts = minattnum + 1;
|
|
if (maxatts > MaxHeapAttributeNumber)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_TOO_MANY_COLUMNS),
|
|
errmsg("tables can have at most %d columns",
|
|
MaxHeapAttributeNumber)));
|
|
i = minattnum + 1;
|
|
|
|
typeTuple = typenameType(colDef->typename);
|
|
tform = (Form_pg_type) GETSTRUCT(typeTuple);
|
|
|
|
/* make sure datatype is legal for a column */
|
|
CheckAttributeType(colDef->colname, HeapTupleGetOid(typeTuple));
|
|
|
|
attributeTuple = heap_addheader(Natts_pg_attribute,
|
|
false,
|
|
ATTRIBUTE_TUPLE_SIZE,
|
|
(void *) &attributeD);
|
|
|
|
attribute = (Form_pg_attribute) GETSTRUCT(attributeTuple);
|
|
|
|
attribute->attrelid = myrelid;
|
|
namestrcpy(&(attribute->attname), colDef->colname);
|
|
attribute->atttypid = HeapTupleGetOid(typeTuple);
|
|
attribute->attstattarget = -1;
|
|
attribute->attlen = tform->typlen;
|
|
attribute->attcacheoff = -1;
|
|
attribute->atttypmod = colDef->typename->typmod;
|
|
attribute->attnum = i;
|
|
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;
|
|
|
|
ReleaseSysCache(typeTuple);
|
|
|
|
simple_heap_insert(attrdesc, attributeTuple);
|
|
|
|
/* Update indexes on pg_attribute */
|
|
CatalogUpdateIndexes(attrdesc, attributeTuple);
|
|
|
|
heap_close(attrdesc, RowExclusiveLock);
|
|
|
|
/*
|
|
* Update number of attributes in pg_class tuple
|
|
*/
|
|
((Form_pg_class) GETSTRUCT(reltup))->relnatts = maxatts;
|
|
|
|
simple_heap_update(pgclass, &reltup->t_self, reltup);
|
|
|
|
/* keep catalog indexes current */
|
|
CatalogUpdateIndexes(pgclass, reltup);
|
|
|
|
heap_freetuple(reltup);
|
|
|
|
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.
|
|
*/
|
|
AddRelationRawConstraints(rel, list_make1(rawEnt), NIL);
|
|
|
|
/* 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 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.
|
|
*
|
|
* Note: we use build_column_default, and not just the cooked default
|
|
* returned by AddRelationRawConstraints, so that the right thing happens
|
|
* when a datatype's default applies.
|
|
*/
|
|
defval = (Expr *) build_column_default(rel, attribute->attnum);
|
|
if (defval)
|
|
{
|
|
NewColumnValue *newval;
|
|
|
|
newval = (NewColumnValue *) palloc0(sizeof(NewColumnValue));
|
|
newval->attnum = attribute->attnum;
|
|
newval->expr = defval;
|
|
|
|
tab->newvals = lappend(tab->newvals, newval);
|
|
}
|
|
|
|
/*
|
|
* Add needed dependency entries for the new column.
|
|
*/
|
|
add_column_datatype_dependency(myrelid, i, attribute->atttypid);
|
|
if (colDef->support != NULL)
|
|
add_column_support_dependency(myrelid, i, colDef->support);
|
|
}
|
|
|
|
/*
|
|
* 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 = RelOid_pg_class;
|
|
myself.objectId = relid;
|
|
myself.objectSubId = attnum;
|
|
referenced.classId = RelOid_pg_type;
|
|
referenced.objectId = typid;
|
|
referenced.objectSubId = 0;
|
|
recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
|
|
}
|
|
|
|
/*
|
|
* Install a dependency for a column's supporting relation (serial sequence).
|
|
*/
|
|
static void
|
|
add_column_support_dependency(Oid relid, int32 attnum, RangeVar *support)
|
|
{
|
|
ObjectAddress colobject,
|
|
suppobject;
|
|
|
|
colobject.classId = RelOid_pg_class;
|
|
colobject.objectId = relid;
|
|
colobject.objectSubId = attnum;
|
|
suppobject.classId = RelOid_pg_class;
|
|
suppobject.objectId = RangeVarGetRelid(support, false);
|
|
suppobject.objectSubId = 0;
|
|
recordDependencyOn(&suppobject, &colobject, DEPENDENCY_INTERNAL);
|
|
}
|
|
|
|
/*
|
|
* ALTER TABLE ALTER COLUMN DROP NOT NULL
|
|
*/
|
|
static void
|
|
ATExecDropNotNull(Relation rel, const char *colName)
|
|
{
|
|
HeapTuple tuple;
|
|
AttrNumber attnum;
|
|
Relation attr_rel;
|
|
List *indexoidlist;
|
|
ListCell *indexoidscan;
|
|
|
|
/*
|
|
* lookup the attribute
|
|
*/
|
|
attr_rel = heap_openr(AttributeRelationName, 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
|
|
*/
|
|
|
|
/* 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 = SearchSysCache(INDEXRELID,
|
|
ObjectIdGetDatum(indexoid),
|
|
0, 0, 0);
|
|
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[i] == attnum)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
|
|
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);
|
|
}
|
|
|
|
heap_close(attr_rel, RowExclusiveLock);
|
|
}
|
|
|
|
/*
|
|
* ALTER TABLE ALTER COLUMN SET NOT NULL
|
|
*/
|
|
static void
|
|
ATExecSetNotNull(AlteredTableInfo *tab, Relation rel,
|
|
const char *colName)
|
|
{
|
|
HeapTuple tuple;
|
|
AttrNumber attnum;
|
|
Relation attr_rel;
|
|
NewConstraint *newcon;
|
|
|
|
/*
|
|
* lookup the attribute
|
|
*/
|
|
attr_rel = heap_openr(AttributeRelationName, 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)));
|
|
|
|
/*
|
|
* Okay, actually perform the catalog change ... if needed
|
|
*/
|
|
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 to test the constraint */
|
|
newcon = (NewConstraint *) palloc0(sizeof(NewConstraint));
|
|
newcon->contype = CONSTR_NOTNULL;
|
|
newcon->attnum = attnum;
|
|
newcon->name = "NOT NULL";
|
|
|
|
tab->constraints = lappend(tab->constraints, newcon);
|
|
}
|
|
|
|
heap_close(attr_rel, RowExclusiveLock);
|
|
}
|
|
|
|
/*
|
|
* ALTER TABLE ALTER COLUMN SET/DROP DEFAULT
|
|
*/
|
|
static void
|
|
ATExecColumnDefault(Relation rel, const char *colName,
|
|
Node *newDefault)
|
|
{
|
|
AttrNumber attnum;
|
|
|
|
/*
|
|
* get the number of the attribute
|
|
*/
|
|
attnum = get_attnum(RelationGetRelid(rel), colName);
|
|
if (attnum == InvalidAttrNumber)
|
|
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 */
|
|
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.
|
|
*/
|
|
RemoveAttrDefault(RelationGetRelid(rel), attnum, DROP_RESTRICT, false);
|
|
|
|
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.
|
|
*/
|
|
AddRelationRawConstraints(rel, list_make1(rawEnt), NIL);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* ALTER TABLE ALTER COLUMN SET STATISTICS
|
|
*/
|
|
static void
|
|
ATPrepSetStatistics(Relation rel, const char *colName, Node *flagValue)
|
|
{
|
|
/*
|
|
* We do our own permission checking because (a) we want to allow
|
|
* SET STATISTICS on indexes (for expressional index columns), and
|
|
* (b) we want to allow SET STATISTICS on system catalogs without
|
|
* requiring allowSystemTableMods to be turned on.
|
|
*/
|
|
if (rel->rd_rel->relkind != RELKIND_RELATION &&
|
|
rel->rd_rel->relkind != RELKIND_INDEX)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
|
|
errmsg("\"%s\" is not a table or index",
|
|
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)
|
|
{
|
|
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 > 1000)
|
|
{
|
|
newtarget = 1000;
|
|
ereport(WARNING,
|
|
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
|
|
errmsg("lowering statistics target to %d",
|
|
newtarget)));
|
|
}
|
|
|
|
attrelation = heap_openr(AttributeRelationName, 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))));
|
|
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);
|
|
|
|
heap_freetuple(tuple);
|
|
|
|
heap_close(attrelation, RowExclusiveLock);
|
|
}
|
|
|
|
/*
|
|
* ALTER TABLE ALTER COLUMN SET STORAGE
|
|
*/
|
|
static void
|
|
ATExecSetStorage(Relation rel, const char *colName, Node *newValue)
|
|
{
|
|
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_openr(AttributeRelationName, 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))));
|
|
attrtuple = (Form_pg_attribute) GETSTRUCT(tuple);
|
|
|
|
if (attrtuple->attnum <= 0)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
errmsg("cannot alter system column \"%s\"",
|
|
colName)));
|
|
|
|
/*
|
|
* 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);
|
|
|
|
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
|
|
* 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.) Since DROP COLUMN doesn't need to create any work queue
|
|
* entries for Phase 3, it's okay to recurse internally in this routine
|
|
* without considering the work queue.
|
|
*/
|
|
static void
|
|
ATExecDropColumn(Relation rel, const char *colName,
|
|
DropBehavior behavior,
|
|
bool recurse, bool recursing)
|
|
{
|
|
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, false);
|
|
|
|
/*
|
|
* get the number of the attribute
|
|
*/
|
|
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))));
|
|
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
|
|
* 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));
|
|
|
|
if (children)
|
|
{
|
|
Relation attr_rel;
|
|
ListCell *child;
|
|
|
|
attr_rel = heap_openr(AttributeRelationName, RowExclusiveLock);
|
|
foreach(child, children)
|
|
{
|
|
Oid childrelid = lfirst_oid(child);
|
|
Relation childrel;
|
|
Form_pg_attribute childatt;
|
|
|
|
childrel = heap_open(childrelid, AccessExclusiveLock);
|
|
|
|
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);
|
|
|
|
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
|
|
* decrement its inheritance count; if not, recurse to delete
|
|
* it.
|
|
*/
|
|
if (childatt->attinhcount == 1 && !childatt->attislocal)
|
|
{
|
|
/* Time to delete this child column, too */
|
|
ATExecDropColumn(childrel, colName, behavior, true, true);
|
|
}
|
|
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
|
|
{
|
|
/*
|
|
* If we were told to drop ONLY in this table (no recursion),
|
|
* we need to mark the inheritors' attribute as locally
|
|
* 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 = RelOid_pg_class;
|
|
object.objectId = RelationGetRelid(rel);
|
|
object.objectSubId = attnum;
|
|
|
|
performDeletion(&object, behavior);
|
|
|
|
/*
|
|
* If we dropped the OID column, must adjust pg_class.relhasoids
|
|
*/
|
|
if (attnum == ObjectIdAttributeNumber)
|
|
{
|
|
Relation class_rel;
|
|
Form_pg_class tuple_class;
|
|
|
|
class_rel = heap_openr(RelationRelationName, RowExclusiveLock);
|
|
|
|
tuple = SearchSysCacheCopy(RELOID,
|
|
ObjectIdGetDatum(RelationGetRelid(rel)),
|
|
0, 0, 0);
|
|
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);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* ALTER TABLE ADD INDEX
|
|
*
|
|
* There is no such command in the grammar, but the parser 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)
|
|
{
|
|
bool check_rights;
|
|
bool skip_build;
|
|
bool quiet;
|
|
|
|
Assert(IsA(stmt, IndexStmt));
|
|
|
|
/* suppress schema rights check when rebuilding existing index */
|
|
check_rights = !is_rebuild;
|
|
/* skip index build if phase 3 will have to rewrite table anyway */
|
|
skip_build = (tab->newvals != NIL);
|
|
/* suppress notices when rebuilding existing index */
|
|
quiet = is_rebuild;
|
|
|
|
DefineIndex(stmt->relation, /* relation */
|
|
stmt->idxname, /* index name */
|
|
stmt->accessMethod, /* am name */
|
|
stmt->tableSpace,
|
|
stmt->indexParams, /* parameters */
|
|
(Expr *) stmt->whereClause,
|
|
stmt->rangetable,
|
|
stmt->unique,
|
|
stmt->primary,
|
|
stmt->isconstraint,
|
|
true, /* is_alter_table */
|
|
check_rights,
|
|
skip_build,
|
|
quiet);
|
|
}
|
|
|
|
/*
|
|
* ALTER TABLE ADD CONSTRAINT
|
|
*/
|
|
static void
|
|
ATExecAddConstraint(AlteredTableInfo *tab, Relation rel, Node *newConstraint)
|
|
{
|
|
switch (nodeTag(newConstraint))
|
|
{
|
|
case T_Constraint:
|
|
{
|
|
Constraint *constr = (Constraint *) newConstraint;
|
|
|
|
/*
|
|
* Currently, we only expect to see CONSTR_CHECK nodes
|
|
* arriving here (see the preprocessing done in
|
|
* parser/analyze.c). Use a switch anyway to make it
|
|
* easier to add more code later.
|
|
*/
|
|
switch (constr->contype)
|
|
{
|
|
case CONSTR_CHECK:
|
|
{
|
|
List *newcons;
|
|
ListCell *lcon;
|
|
|
|
/*
|
|
* Call AddRelationRawConstraints to do the work.
|
|
* It returns a list of cooked constraints.
|
|
*/
|
|
newcons = AddRelationRawConstraints(rel, NIL,
|
|
list_make1(constr));
|
|
/* Add each constraint to Phase 3's queue */
|
|
foreach(lcon, newcons)
|
|
{
|
|
CookedConstraint *ccon = (CookedConstraint *) lfirst(lcon);
|
|
NewConstraint *newcon;
|
|
|
|
newcon = (NewConstraint *) palloc0(sizeof(NewConstraint));
|
|
newcon->name = ccon->name;
|
|
newcon->contype = ccon->contype;
|
|
newcon->attnum = ccon->attnum;
|
|
/* ExecQual wants implicit-AND format */
|
|
newcon->qual = (Node *)
|
|
make_ands_implicit((Expr *) ccon->expr);
|
|
|
|
tab->constraints = lappend(tab->constraints,
|
|
newcon);
|
|
}
|
|
break;
|
|
}
|
|
default:
|
|
elog(ERROR, "unrecognized constraint type: %d",
|
|
(int) constr->contype);
|
|
}
|
|
break;
|
|
}
|
|
case T_FkConstraint:
|
|
{
|
|
FkConstraint *fkconstraint = (FkConstraint *) newConstraint;
|
|
|
|
/*
|
|
* Assign or validate constraint name
|
|
*/
|
|
if (fkconstraint->constr_name)
|
|
{
|
|
if (ConstraintNameIsUsed(CONSTRAINT_RELATION,
|
|
RelationGetRelid(rel),
|
|
RelationGetNamespace(rel),
|
|
fkconstraint->constr_name))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_DUPLICATE_OBJECT),
|
|
errmsg("constraint \"%s\" for relation \"%s\" already exists",
|
|
fkconstraint->constr_name,
|
|
RelationGetRelationName(rel))));
|
|
}
|
|
else
|
|
fkconstraint->constr_name =
|
|
ChooseConstraintName(RelationGetRelationName(rel),
|
|
strVal(linitial(fkconstraint->fk_attrs)),
|
|
"fkey",
|
|
RelationGetNamespace(rel),
|
|
NIL);
|
|
|
|
ATAddForeignKeyConstraint(tab, rel, fkconstraint);
|
|
|
|
break;
|
|
}
|
|
default:
|
|
elog(ERROR, "unrecognized node type: %d",
|
|
(int) nodeTag(newConstraint));
|
|
}
|
|
}
|
|
|
|
/*
|
|
* 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/permissions checks
|
|
* for it.
|
|
*/
|
|
static void
|
|
ATAddForeignKeyConstraint(AlteredTableInfo *tab, Relation rel,
|
|
FkConstraint *fkconstraint)
|
|
{
|
|
Relation pkrel;
|
|
AclResult aclresult;
|
|
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];
|
|
int i;
|
|
int numfks,
|
|
numpks;
|
|
Oid indexOid;
|
|
Oid constrOid;
|
|
|
|
/*
|
|
* 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 and permissions checks
|
|
*
|
|
* Note: REFERENCES permissions checks are redundant with CREATE TRIGGER,
|
|
* but we may as well error out sooner instead of later.
|
|
*/
|
|
if (pkrel->rd_rel->relkind != RELKIND_RELATION)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
|
|
errmsg("referenced relation \"%s\" is not a table",
|
|
RelationGetRelationName(pkrel))));
|
|
|
|
aclresult = pg_class_aclcheck(RelationGetRelid(pkrel), GetUserId(),
|
|
ACL_REFERENCES);
|
|
if (aclresult != ACLCHECK_OK)
|
|
aclcheck_error(aclresult, ACL_KIND_CLASS,
|
|
RelationGetRelationName(pkrel));
|
|
|
|
if (!allowSystemTableMods && IsSystemRelation(pkrel))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
|
|
errmsg("permission denied: \"%s\" is a system catalog",
|
|
RelationGetRelationName(pkrel))));
|
|
|
|
aclresult = pg_class_aclcheck(RelationGetRelid(rel), GetUserId(),
|
|
ACL_REFERENCES);
|
|
if (aclresult != ACLCHECK_OK)
|
|
aclcheck_error(aclresult, ACL_KIND_CLASS,
|
|
RelationGetRelationName(rel));
|
|
|
|
/*
|
|
* Disallow reference from permanent table to temp table or vice versa.
|
|
* (The ban on perm->temp is for fairly obvious reasons. The ban on
|
|
* temp->perm is because other backends might need to run the RI triggers
|
|
* on the perm table, but they can't reliably see tuples the owning
|
|
* backend has created in the temp table, because non-shared buffers
|
|
* are used for temp tables.)
|
|
*/
|
|
if (isTempNamespace(RelationGetNamespace(pkrel)))
|
|
{
|
|
if (!isTempNamespace(RelationGetNamespace(rel)))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
|
|
errmsg("cannot reference temporary table from permanent table constraint")));
|
|
}
|
|
else
|
|
{
|
|
if (isTempNamespace(RelationGetNamespace(rel)))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
|
|
errmsg("cannot reference permanent table from temporary table constraint")));
|
|
}
|
|
|
|
/*
|
|
* 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));
|
|
|
|
numfks = transformColumnNameList(RelationGetRelid(rel),
|
|
fkconstraint->fk_attrs,
|
|
fkattnum, fktypoid);
|
|
|
|
/*
|
|
* 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);
|
|
}
|
|
|
|
/* Be sure referencing and referenced column types are comparable */
|
|
if (numfks != numpks)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_INVALID_FOREIGN_KEY),
|
|
errmsg("number of referencing and referenced columns for foreign key disagree")));
|
|
|
|
for (i = 0; i < numpks; i++)
|
|
{
|
|
/*
|
|
* pktypoid[i] is the primary key table's i'th key's type
|
|
* fktypoid[i] is the foreign key table's i'th key's type
|
|
*
|
|
* Note that we look for an operator with the PK type on the left;
|
|
* when the types are different this is critical because the PK index
|
|
* will need operators with the indexkey on the left. (Ordinarily
|
|
* both commutator operators will exist if either does, but we won't
|
|
* get the right answer from the test below on opclass membership
|
|
* unless we select the proper operator.)
|
|
*/
|
|
Operator o = oper(list_make1(makeString("=")),
|
|
pktypoid[i], fktypoid[i], true);
|
|
|
|
if (o == NULL)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_UNDEFINED_FUNCTION),
|
|
errmsg("foreign key constraint \"%s\" "
|
|
"cannot be implemented",
|
|
fkconstraint->constr_name),
|
|
errdetail("Key columns \"%s\" and \"%s\" "
|
|
"are of incompatible types: %s and %s.",
|
|
strVal(list_nth(fkconstraint->fk_attrs, i)),
|
|
strVal(list_nth(fkconstraint->pk_attrs, i)),
|
|
format_type_be(fktypoid[i]),
|
|
format_type_be(pktypoid[i]))));
|
|
|
|
/*
|
|
* Check that the found operator is compatible with the PK index,
|
|
* and generate a warning if not, since otherwise costly seqscans
|
|
* will be incurred to check FK validity.
|
|
*/
|
|
if (!op_in_opclass(oprid(o), opclasses[i]))
|
|
ereport(WARNING,
|
|
(errmsg("foreign key constraint \"%s\" "
|
|
"will require costly sequential scans",
|
|
fkconstraint->constr_name),
|
|
errdetail("Key columns \"%s\" and \"%s\" "
|
|
"are of different types: %s and %s.",
|
|
strVal(list_nth(fkconstraint->fk_attrs, i)),
|
|
strVal(list_nth(fkconstraint->pk_attrs, i)),
|
|
format_type_be(fktypoid[i]),
|
|
format_type_be(pktypoid[i]))));
|
|
|
|
ReleaseSysCache(o);
|
|
}
|
|
|
|
/*
|
|
* Tell Phase 3 to check that the constraint is satisfied by existing rows
|
|
* (we can skip this during table creation).
|
|
*/
|
|
if (!fkconstraint->skip_validation)
|
|
{
|
|
NewConstraint *newcon;
|
|
|
|
newcon = (NewConstraint *) palloc0(sizeof(NewConstraint));
|
|
newcon->name = fkconstraint->constr_name;
|
|
newcon->contype = CONSTR_FOREIGN;
|
|
newcon->refrelid = RelationGetRelid(pkrel);
|
|
newcon->qual = (Node *) fkconstraint;
|
|
|
|
tab->constraints = lappend(tab->constraints, newcon);
|
|
}
|
|
|
|
/*
|
|
* Record the FK constraint in pg_constraint.
|
|
*/
|
|
constrOid = CreateConstraintEntry(fkconstraint->constr_name,
|
|
RelationGetNamespace(rel),
|
|
CONSTRAINT_FOREIGN,
|
|
fkconstraint->deferrable,
|
|
fkconstraint->initdeferred,
|
|
RelationGetRelid(rel),
|
|
fkattnum,
|
|
numfks,
|
|
InvalidOid, /* not a domain
|
|
* constraint */
|
|
RelationGetRelid(pkrel),
|
|
pkattnum,
|
|
numpks,
|
|
fkconstraint->fk_upd_action,
|
|
fkconstraint->fk_del_action,
|
|
fkconstraint->fk_matchtype,
|
|
indexOid,
|
|
NULL, /* no check constraint */
|
|
NULL,
|
|
NULL);
|
|
|
|
/*
|
|
* Create the triggers that will enforce the constraint.
|
|
*/
|
|
createForeignKeyTriggers(rel, fkconstraint, constrOid);
|
|
|
|
/*
|
|
* Close pk table, but keep lock until we've committed.
|
|
*/
|
|
heap_close(pkrel, NoLock);
|
|
}
|
|
|
|
|
|
/*
|
|
* 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),
|
|
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
|
|
* for the pkrel. Also return the index OID and index opclasses of the
|
|
* index supporting the primary key.
|
|
*
|
|
* 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;
|
|
int i;
|
|
|
|
/*
|
|
* 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 (hopefully there isn't more than one such).
|
|
*/
|
|
indexoidlist = RelationGetIndexList(pkrel);
|
|
|
|
foreach(indexoidscan, indexoidlist)
|
|
{
|
|
Oid indexoid = lfirst_oid(indexoidscan);
|
|
|
|
indexTuple = SearchSysCache(INDEXRELID,
|
|
ObjectIdGetDatum(indexoid),
|
|
0, 0, 0);
|
|
if (!HeapTupleIsValid(indexTuple))
|
|
elog(ERROR, "cache lookup failed for index %u", indexoid);
|
|
indexStruct = (Form_pg_index) GETSTRUCT(indexTuple);
|
|
if (indexStruct->indisprimary)
|
|
{
|
|
*indexOid = indexoid;
|
|
break;
|
|
}
|
|
ReleaseSysCache(indexTuple);
|
|
indexStruct = NULL;
|
|
}
|
|
|
|
list_free(indexoidlist);
|
|
|
|
/*
|
|
* Check that we found it
|
|
*/
|
|
if (indexStruct == NULL)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_UNDEFINED_OBJECT),
|
|
errmsg("there is no primary key for referenced table \"%s\"",
|
|
RelationGetRelationName(pkrel))));
|
|
|
|
/*
|
|
* 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[i];
|
|
|
|
attnums[i] = pkattno;
|
|
atttypids[i] = attnumTypeId(pkrel, pkattno);
|
|
opclasses[i] = indexStruct->indclass[i];
|
|
*attnamelist = lappend(*attnamelist,
|
|
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,
|
|
Oid *opclasses) /* output parameter */
|
|
{
|
|
Oid indexoid = InvalidOid;
|
|
bool found = false;
|
|
List *indexoidlist;
|
|
ListCell *indexoidscan;
|
|
|
|
/*
|
|
* 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;
|
|
int i,
|
|
j;
|
|
|
|
indexoid = lfirst_oid(indexoidscan);
|
|
indexTuple = SearchSysCache(INDEXRELID,
|
|
ObjectIdGetDatum(indexoid),
|
|
0, 0, 0);
|
|
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
|
|
* partial index; forget it if there are any expressions, too
|
|
*/
|
|
if (indexStruct->indnatts == numattrs &&
|
|
indexStruct->indisunique &&
|
|
heap_attisnull(indexTuple, Anum_pg_index_indpred) &&
|
|
heap_attisnull(indexTuple, Anum_pg_index_indexprs))
|
|
{
|
|
/*
|
|
* 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[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[i])
|
|
{
|
|
opclasses[j] = indexStruct->indclass[i];
|
|
found = true;
|
|
break;
|
|
}
|
|
}
|
|
if (!found)
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
ReleaseSysCache(indexTuple);
|
|
if (found)
|
|
break;
|
|
}
|
|
|
|
if (!found)
|
|
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;
|
|
}
|
|
|
|
/*
|
|
* Scan the existing rows in a table to verify they meet a proposed FK
|
|
* constraint.
|
|
*
|
|
* Caller must have opened and locked both relations.
|
|
*/
|
|
static void
|
|
validateForeignKeyConstraint(FkConstraint *fkconstraint,
|
|
Relation rel,
|
|
Relation pkrel)
|
|
{
|
|
HeapScanDesc scan;
|
|
HeapTuple tuple;
|
|
Trigger trig;
|
|
ListCell *list;
|
|
int count;
|
|
|
|
/*
|
|
* 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(fkconstraint, 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.
|
|
*/
|
|
MemSet(&trig, 0, sizeof(trig));
|
|
trig.tgoid = InvalidOid;
|
|
trig.tgname = fkconstraint->constr_name;
|
|
trig.tgenabled = TRUE;
|
|
trig.tgisconstraint = TRUE;
|
|
trig.tgconstrrelid = RelationGetRelid(pkrel);
|
|
trig.tgdeferrable = FALSE;
|
|
trig.tginitdeferred = FALSE;
|
|
|
|
trig.tgargs = (char **) palloc(sizeof(char *) *
|
|
(4 + list_length(fkconstraint->fk_attrs)
|
|
+ list_length(fkconstraint->pk_attrs)));
|
|
|
|
trig.tgargs[0] = trig.tgname;
|
|
trig.tgargs[1] = RelationGetRelationName(rel);
|
|
trig.tgargs[2] = RelationGetRelationName(pkrel);
|
|
trig.tgargs[3] = fkMatchTypeToString(fkconstraint->fk_matchtype);
|
|
count = 4;
|
|
foreach(list, fkconstraint->fk_attrs)
|
|
{
|
|
char *fk_at = strVal(lfirst(list));
|
|
|
|
trig.tgargs[count] = fk_at;
|
|
count += 2;
|
|
}
|
|
count = 5;
|
|
foreach(list, fkconstraint->pk_attrs)
|
|
{
|
|
char *pk_at = strVal(lfirst(list));
|
|
|
|
trig.tgargs[count] = pk_at;
|
|
count += 2;
|
|
}
|
|
trig.tgnargs = count - 1;
|
|
|
|
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;
|
|
|
|
fcinfo.context = (Node *) &trigdata;
|
|
|
|
RI_FKey_check_ins(&fcinfo);
|
|
}
|
|
|
|
heap_endscan(scan);
|
|
|
|
pfree(trig.tgargs);
|
|
}
|
|
|
|
/*
|
|
* Create the triggers that implement an FK constraint.
|
|
*/
|
|
static void
|
|
createForeignKeyTriggers(Relation rel, FkConstraint *fkconstraint,
|
|
Oid constrOid)
|
|
{
|
|
RangeVar *myRel;
|
|
CreateTrigStmt *fk_trigger;
|
|
ListCell *fk_attr;
|
|
ListCell *pk_attr;
|
|
ObjectAddress trigobj,
|
|
constrobj;
|
|
|
|
/*
|
|
* Reconstruct a RangeVar for my relation (not passed in,
|
|
* unfortunately).
|
|
*/
|
|
myRel = makeRangeVar(get_namespace_name(RelationGetNamespace(rel)),
|
|
pstrdup(RelationGetRelationName(rel)));
|
|
|
|
/*
|
|
* Preset objectAddress fields
|
|
*/
|
|
constrobj.classId = get_system_catalog_relid(ConstraintRelationName);
|
|
constrobj.objectId = constrOid;
|
|
constrobj.objectSubId = 0;
|
|
trigobj.classId = get_system_catalog_relid(TriggerRelationName);
|
|
trigobj.objectSubId = 0;
|
|
|
|
/* Make changes-so-far visible */
|
|
CommandCounterIncrement();
|
|
|
|
/*
|
|
* Build and execute a CREATE CONSTRAINT TRIGGER statement for the
|
|
* CHECK action.
|
|
*/
|
|
fk_trigger = makeNode(CreateTrigStmt);
|
|
fk_trigger->trigname = fkconstraint->constr_name;
|
|
fk_trigger->relation = myRel;
|
|
fk_trigger->funcname = SystemFuncName("RI_FKey_check_ins");
|
|
fk_trigger->before = false;
|
|
fk_trigger->row = true;
|
|
fk_trigger->actions[0] = 'i';
|
|
fk_trigger->actions[1] = 'u';
|
|
fk_trigger->actions[2] = '\0';
|
|
|
|
fk_trigger->isconstraint = true;
|
|
fk_trigger->deferrable = fkconstraint->deferrable;
|
|
fk_trigger->initdeferred = fkconstraint->initdeferred;
|
|
fk_trigger->constrrel = fkconstraint->pktable;
|
|
|
|
fk_trigger->args = NIL;
|
|
fk_trigger->args = lappend(fk_trigger->args,
|
|
makeString(fkconstraint->constr_name));
|
|
fk_trigger->args = lappend(fk_trigger->args,
|
|
makeString(myRel->relname));
|
|
fk_trigger->args = lappend(fk_trigger->args,
|
|
makeString(fkconstraint->pktable->relname));
|
|
fk_trigger->args = lappend(fk_trigger->args,
|
|
makeString(fkMatchTypeToString(fkconstraint->fk_matchtype)));
|
|
if (list_length(fkconstraint->fk_attrs) != list_length(fkconstraint->pk_attrs))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_INVALID_FOREIGN_KEY),
|
|
errmsg("number of referencing and referenced columns for foreign key disagree")));
|
|
|
|
forboth(fk_attr, fkconstraint->fk_attrs,
|
|
pk_attr, fkconstraint->pk_attrs)
|
|
{
|
|
fk_trigger->args = lappend(fk_trigger->args, lfirst(fk_attr));
|
|
fk_trigger->args = lappend(fk_trigger->args, lfirst(pk_attr));
|
|
}
|
|
|
|
trigobj.objectId = CreateTrigger(fk_trigger, true);
|
|
|
|
/* Register dependency from trigger to constraint */
|
|
recordDependencyOn(&trigobj, &constrobj, DEPENDENCY_INTERNAL);
|
|
|
|
/* 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 = fkconstraint->constr_name;
|
|
fk_trigger->relation = fkconstraint->pktable;
|
|
fk_trigger->before = false;
|
|
fk_trigger->row = true;
|
|
fk_trigger->actions[0] = 'd';
|
|
fk_trigger->actions[1] = '\0';
|
|
|
|
fk_trigger->isconstraint = true;
|
|
fk_trigger->deferrable = fkconstraint->deferrable;
|
|
fk_trigger->initdeferred = fkconstraint->initdeferred;
|
|
fk_trigger->constrrel = myRel;
|
|
switch (fkconstraint->fk_del_action)
|
|
{
|
|
case FKCONSTR_ACTION_NOACTION:
|
|
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->funcname = SystemFuncName("RI_FKey_cascade_del");
|
|
break;
|
|
case FKCONSTR_ACTION_SETNULL:
|
|
fk_trigger->funcname = SystemFuncName("RI_FKey_setnull_del");
|
|
break;
|
|
case FKCONSTR_ACTION_SETDEFAULT:
|
|
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;
|
|
fk_trigger->args = lappend(fk_trigger->args,
|
|
makeString(fkconstraint->constr_name));
|
|
fk_trigger->args = lappend(fk_trigger->args,
|
|
makeString(myRel->relname));
|
|
fk_trigger->args = lappend(fk_trigger->args,
|
|
makeString(fkconstraint->pktable->relname));
|
|
fk_trigger->args = lappend(fk_trigger->args,
|
|
makeString(fkMatchTypeToString(fkconstraint->fk_matchtype)));
|
|
forboth(fk_attr, fkconstraint->fk_attrs,
|
|
pk_attr, fkconstraint->pk_attrs)
|
|
{
|
|
fk_trigger->args = lappend(fk_trigger->args, lfirst(fk_attr));
|
|
fk_trigger->args = lappend(fk_trigger->args, lfirst(pk_attr));
|
|
}
|
|
|
|
trigobj.objectId = CreateTrigger(fk_trigger, true);
|
|
|
|
/* Register dependency from trigger to constraint */
|
|
recordDependencyOn(&trigobj, &constrobj, DEPENDENCY_INTERNAL);
|
|
|
|
/* 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 = fkconstraint->constr_name;
|
|
fk_trigger->relation = fkconstraint->pktable;
|
|
fk_trigger->before = false;
|
|
fk_trigger->row = true;
|
|
fk_trigger->actions[0] = 'u';
|
|
fk_trigger->actions[1] = '\0';
|
|
fk_trigger->isconstraint = true;
|
|
fk_trigger->deferrable = fkconstraint->deferrable;
|
|
fk_trigger->initdeferred = fkconstraint->initdeferred;
|
|
fk_trigger->constrrel = myRel;
|
|
switch (fkconstraint->fk_upd_action)
|
|
{
|
|
case FKCONSTR_ACTION_NOACTION:
|
|
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->funcname = SystemFuncName("RI_FKey_cascade_upd");
|
|
break;
|
|
case FKCONSTR_ACTION_SETNULL:
|
|
fk_trigger->funcname = SystemFuncName("RI_FKey_setnull_upd");
|
|
break;
|
|
case FKCONSTR_ACTION_SETDEFAULT:
|
|
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;
|
|
fk_trigger->args = lappend(fk_trigger->args,
|
|
makeString(fkconstraint->constr_name));
|
|
fk_trigger->args = lappend(fk_trigger->args,
|
|
makeString(myRel->relname));
|
|
fk_trigger->args = lappend(fk_trigger->args,
|
|
makeString(fkconstraint->pktable->relname));
|
|
fk_trigger->args = lappend(fk_trigger->args,
|
|
makeString(fkMatchTypeToString(fkconstraint->fk_matchtype)));
|
|
forboth(fk_attr, fkconstraint->fk_attrs,
|
|
pk_attr, fkconstraint->pk_attrs)
|
|
{
|
|
fk_trigger->args = lappend(fk_trigger->args, lfirst(fk_attr));
|
|
fk_trigger->args = lappend(fk_trigger->args, lfirst(pk_attr));
|
|
}
|
|
|
|
trigobj.objectId = CreateTrigger(fk_trigger, true);
|
|
|
|
/* Register dependency from trigger to constraint */
|
|
recordDependencyOn(&trigobj, &constrobj, DEPENDENCY_INTERNAL);
|
|
}
|
|
|
|
/*
|
|
* fkMatchTypeToString -
|
|
* convert FKCONSTR_MATCH_xxx code to string to use in trigger args
|
|
*/
|
|
static char *
|
|
fkMatchTypeToString(char match_type)
|
|
{
|
|
switch (match_type)
|
|
{
|
|
case FKCONSTR_MATCH_FULL:
|
|
return pstrdup("FULL");
|
|
case FKCONSTR_MATCH_PARTIAL:
|
|
return pstrdup("PARTIAL");
|
|
case FKCONSTR_MATCH_UNSPECIFIED:
|
|
return pstrdup("UNSPECIFIED");
|
|
default:
|
|
elog(ERROR, "unrecognized match type: %d",
|
|
(int) match_type);
|
|
}
|
|
return NULL; /* can't get here */
|
|
}
|
|
|
|
/*
|
|
* ALTER TABLE DROP CONSTRAINT
|
|
*/
|
|
static void
|
|
ATPrepDropConstraint(List **wqueue, Relation rel,
|
|
bool recurse, AlterTableCmd *cmd)
|
|
{
|
|
/*
|
|
* We don't want errors or noise from child tables, so we have to pass
|
|
* down a modified command.
|
|
*/
|
|
if (recurse)
|
|
{
|
|
AlterTableCmd *childCmd = copyObject(cmd);
|
|
|
|
childCmd->subtype = AT_DropConstraintQuietly;
|
|
ATSimpleRecursion(wqueue, rel, childCmd, recurse);
|
|
}
|
|
}
|
|
|
|
static void
|
|
ATExecDropConstraint(Relation rel, const char *constrName,
|
|
DropBehavior behavior, bool quiet)
|
|
{
|
|
int deleted;
|
|
|
|
deleted = RemoveRelConstraints(rel, constrName, behavior);
|
|
|
|
if (!quiet)
|
|
{
|
|
/* If zero constraints deleted, complain */
|
|
if (deleted == 0)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_UNDEFINED_OBJECT),
|
|
errmsg("constraint \"%s\" does not exist",
|
|
constrName)));
|
|
/* Otherwise if more than one constraint deleted, notify */
|
|
else if (deleted > 1)
|
|
ereport(NOTICE,
|
|
(errmsg("multiple constraints named \"%s\" were dropped",
|
|
constrName)));
|
|
}
|
|
}
|
|
|
|
/*
|
|
* ALTER COLUMN TYPE
|
|
*/
|
|
static void
|
|
ATPrepAlterColumnType(List **wqueue,
|
|
AlteredTableInfo *tab, Relation rel,
|
|
bool recurse, bool recursing,
|
|
AlterTableCmd *cmd)
|
|
{
|
|
char *colName = cmd->name;
|
|
TypeName *typename = (TypeName *) cmd->def;
|
|
HeapTuple tuple;
|
|
Form_pg_attribute attTup;
|
|
AttrNumber attnum;
|
|
Oid targettype;
|
|
Node *transform;
|
|
NewColumnValue *newval;
|
|
ParseState *pstate = make_parsestate(NULL);
|
|
|
|
/* 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 */
|
|
targettype = LookupTypeName(typename);
|
|
if (!OidIsValid(targettype))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_UNDEFINED_OBJECT),
|
|
errmsg("type \"%s\" does not exist",
|
|
TypeNameToString(typename))));
|
|
|
|
/* make sure datatype is legal for a column */
|
|
CheckAttributeType(colName, targettype);
|
|
|
|
/*
|
|
* 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 rowtype.
|
|
*/
|
|
if (cmd->transform)
|
|
{
|
|
RangeTblEntry *rte;
|
|
|
|
/* Expression must be able to access vars of old table */
|
|
rte = addRangeTableEntryForRelation(pstate,
|
|
RelationGetRelid(rel),
|
|
makeAlias(RelationGetRelationName(rel), NIL),
|
|
false,
|
|
true);
|
|
addRTEtoQuery(pstate, rte, false, true);
|
|
|
|
transform = transformExpr(pstate, cmd->transform);
|
|
|
|
/* It can't return a set */
|
|
if (expression_returns_set(transform))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_DATATYPE_MISMATCH),
|
|
errmsg("transform expression must not return a set")));
|
|
|
|
/* No subplans or aggregates, either... */
|
|
if (pstate->p_hasSubLinks)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
errmsg("cannot use subquery in transform expression")));
|
|
if (pstate->p_hasAggs)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_GROUPING_ERROR),
|
|
errmsg("cannot use aggregate function in transform expression")));
|
|
}
|
|
else
|
|
{
|
|
transform = (Node *) makeVar(1, attnum,
|
|
attTup->atttypid, attTup->atttypmod,
|
|
0);
|
|
}
|
|
|
|
transform = coerce_to_target_type(pstate,
|
|
transform, exprType(transform),
|
|
targettype, typename->typmod,
|
|
COERCION_ASSIGNMENT,
|
|
COERCE_IMPLICIT_CAST);
|
|
if (transform == NULL)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_DATATYPE_MISMATCH),
|
|
errmsg("column \"%s\" cannot be cast to type \"%s\"",
|
|
colName, TypeNameToString(typename))));
|
|
|
|
/*
|
|
* 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);
|
|
|
|
ReleaseSysCache(tuple);
|
|
|
|
/*
|
|
* 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);
|
|
else if (!recursing &&
|
|
find_inheritance_children(RelationGetRelid(rel)) != NIL)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
|
|
errmsg("type of inherited column \"%s\" must be changed in child tables too",
|
|
colName)));
|
|
}
|
|
|
|
static void
|
|
ATExecAlterColumnType(AlteredTableInfo *tab, Relation rel,
|
|
const char *colName, TypeName *typename)
|
|
{
|
|
HeapTuple heapTup;
|
|
Form_pg_attribute attTup;
|
|
AttrNumber attnum;
|
|
HeapTuple typeTuple;
|
|
Form_pg_type tform;
|
|
Oid targettype;
|
|
Node *defaultexpr;
|
|
Relation attrelation;
|
|
Relation depRel;
|
|
ScanKeyData key[3];
|
|
SysScanDesc scan;
|
|
HeapTuple depTup;
|
|
|
|
attrelation = heap_openr(AttributeRelationName, RowExclusiveLock);
|
|
|
|
/* Look up the target column */
|
|
heapTup = SearchSysCacheCopyAttName(RelationGetRelid(rel), colName);
|
|
if (!HeapTupleIsValid(heapTup)) /* shouldn't happen */
|
|
ereport(ERROR,
|
|
(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 */
|
|
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) */
|
|
typeTuple = typenameType(typename);
|
|
tform = (Form_pg_type) GETSTRUCT(typeTuple);
|
|
targettype = HeapTupleGetOid(typeTuple);
|
|
|
|
/*
|
|
* 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.)
|
|
*/
|
|
if (attTup->atthasdef)
|
|
{
|
|
defaultexpr = build_column_default(rel, attnum);
|
|
Assert(defaultexpr);
|
|
defaultexpr = coerce_to_target_type(NULL, /* no UNKNOWN params */
|
|
defaultexpr, exprType(defaultexpr),
|
|
targettype, typename->typmod,
|
|
COERCION_ASSIGNMENT,
|
|
COERCE_IMPLICIT_CAST);
|
|
if (defaultexpr == NULL)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_DATATYPE_MISMATCH),
|
|
errmsg("default for column \"%s\" cannot be cast to type \"%s\"",
|
|
colName, TypeNameToString(typename))));
|
|
}
|
|
else
|
|
defaultexpr = NULL;
|
|
|
|
/*
|
|
* 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
|
|
* 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
|
|
* that implements a constraint will not show a direct dependency on the
|
|
* column.
|
|
*/
|
|
depRel = heap_openr(DependRelationName, RowExclusiveLock);
|
|
|
|
ScanKeyInit(&key[0],
|
|
Anum_pg_depend_refclassid,
|
|
BTEqualStrategyNumber, F_OIDEQ,
|
|
ObjectIdGetDatum(RelOid_pg_class));
|
|
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, DependReferenceIndex, true,
|
|
SnapshotNow, 3, key);
|
|
|
|
while (HeapTupleIsValid(depTup = systable_getnext(scan)))
|
|
{
|
|
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:
|
|
{
|
|
char relKind = get_rel_relkind(foundObject.objectId);
|
|
|
|
if (relKind == RELKIND_INDEX)
|
|
{
|
|
Assert(foundObject.objectSubId == 0);
|
|
if (!list_member_oid(tab->changedIndexOids, foundObject.objectId))
|
|
{
|
|
tab->changedIndexOids = lappend_oid(tab->changedIndexOids,
|
|
foundObject.objectId);
|
|
tab->changedIndexDefs = lappend(tab->changedIndexDefs,
|
|
pg_get_indexdef_string(foundObject.objectId));
|
|
}
|
|
}
|
|
else if (relKind == RELKIND_SEQUENCE)
|
|
{
|
|
/*
|
|
* This must be a SERIAL column's sequence. We need not
|
|
* do anything to it.
|
|
*/
|
|
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))
|
|
{
|
|
tab->changedConstraintOids = lappend_oid(tab->changedConstraintOids,
|
|
foundObject.objectId);
|
|
tab->changedConstraintDefs = lappend(tab->changedConstraintDefs,
|
|
pg_get_constraintdef_string(foundObject.objectId));
|
|
}
|
|
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_DEFAULT:
|
|
/*
|
|
* 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_CONVERSION:
|
|
case OCLASS_LANGUAGE:
|
|
case OCLASS_OPERATOR:
|
|
case OCLASS_OPCLASS:
|
|
case OCLASS_TRIGGER:
|
|
case OCLASS_SCHEMA:
|
|
/*
|
|
* 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
|
|
* thing we should find is the dependency on the column datatype,
|
|
* which we want to remove.
|
|
*/
|
|
ScanKeyInit(&key[0],
|
|
Anum_pg_depend_classid,
|
|
BTEqualStrategyNumber, F_OIDEQ,
|
|
ObjectIdGetDatum(RelOid_pg_class));
|
|
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, DependDependerIndex, true,
|
|
SnapshotNow, 3, key);
|
|
|
|
while (HeapTupleIsValid(depTup = systable_getnext(scan)))
|
|
{
|
|
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 != RelOid_pg_type ||
|
|
foundDep->refobjid != attTup->atttypid)
|
|
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. (Note heapTup is
|
|
* a copy of the syscache entry, so okay to scribble on.)
|
|
*/
|
|
attTup->atttypid = targettype;
|
|
attTup->atttypmod = typename->typmod;
|
|
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 dependency on new datatype */
|
|
add_column_datatype_dependency(RelationGetRelid(rel), attnum, targettype);
|
|
|
|
/* Drop any pg_statistic entry for the column, since it's now wrong type */
|
|
RemoveStatistics(RelationGetRelid(rel), attnum);
|
|
|
|
/*
|
|
* 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();
|
|
|
|
/*
|
|
* 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);
|
|
|
|
StoreAttrDefault(rel, attnum, nodeToString(defaultexpr));
|
|
}
|
|
|
|
/* Cleanup */
|
|
heap_freetuple(heapTup);
|
|
}
|
|
|
|
/*
|
|
* 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)
|
|
{
|
|
ObjectAddress obj;
|
|
ListCell *l;
|
|
|
|
/*
|
|
* 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.
|
|
*/
|
|
foreach(l, tab->changedIndexDefs)
|
|
{
|
|
ATPostAlterTypeParse((char *) lfirst(l), wqueue);
|
|
}
|
|
foreach(l, tab->changedConstraintDefs)
|
|
{
|
|
ATPostAlterTypeParse((char *) lfirst(l), wqueue);
|
|
}
|
|
|
|
/*
|
|
* Now we can drop the existing constraints and indexes --- constraints
|
|
* first, since some of them might depend on the indexes. It should be
|
|
* okay to use DROP_RESTRICT here, since nothing else should be depending
|
|
* on these objects.
|
|
*/
|
|
if (tab->changedConstraintOids)
|
|
obj.classId = get_system_catalog_relid(ConstraintRelationName);
|
|
foreach(l, tab->changedConstraintOids)
|
|
{
|
|
obj.objectId = lfirst_oid(l);
|
|
obj.objectSubId = 0;
|
|
performDeletion(&obj, DROP_RESTRICT);
|
|
}
|
|
|
|
obj.classId = RelOid_pg_class;
|
|
foreach(l, tab->changedIndexOids)
|
|
{
|
|
obj.objectId = lfirst_oid(l);
|
|
obj.objectSubId = 0;
|
|
performDeletion(&obj, DROP_RESTRICT);
|
|
}
|
|
|
|
/*
|
|
* The objects will get recreated during subsequent passes over the
|
|
* work queue.
|
|
*/
|
|
}
|
|
|
|
static void
|
|
ATPostAlterTypeParse(char *cmd, List **wqueue)
|
|
{
|
|
List *raw_parsetree_list;
|
|
List *querytree_list;
|
|
ListCell *list_item;
|
|
|
|
/*
|
|
* We expect that we only have to do raw parsing and parse analysis, not
|
|
* any rule rewriting, since these will all be utility statements.
|
|
*/
|
|
raw_parsetree_list = raw_parser(cmd);
|
|
querytree_list = NIL;
|
|
foreach(list_item, raw_parsetree_list)
|
|
{
|
|
Node *parsetree = (Node *) lfirst(list_item);
|
|
|
|
querytree_list = list_concat(querytree_list,
|
|
parse_analyze(parsetree, NULL, 0));
|
|
}
|
|
|
|
/*
|
|
* Attach each generated command to the proper place in the work queue.
|
|
* Note this could result in creation of entirely new work-queue entries.
|
|
*/
|
|
foreach(list_item, querytree_list)
|
|
{
|
|
Query *query = (Query *) lfirst(list_item);
|
|
Relation rel;
|
|
AlteredTableInfo *tab;
|
|
|
|
Assert(IsA(query, Query));
|
|
Assert(query->commandType == CMD_UTILITY);
|
|
switch (nodeTag(query->utilityStmt))
|
|
{
|
|
case T_IndexStmt:
|
|
{
|
|
IndexStmt *stmt = (IndexStmt *) query->utilityStmt;
|
|
AlterTableCmd *newcmd;
|
|
|
|
rel = relation_openrv(stmt->relation, AccessExclusiveLock);
|
|
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 *) query->utilityStmt;
|
|
ListCell *lcmd;
|
|
|
|
rel = relation_openrv(stmt->relation, AccessExclusiveLock);
|
|
tab = ATGetQueueEntry(wqueue, rel);
|
|
foreach(lcmd, stmt->cmds)
|
|
{
|
|
AlterTableCmd *cmd = (AlterTableCmd *) lfirst(lcmd);
|
|
|
|
switch (cmd->subtype)
|
|
{
|
|
case AT_AddIndex:
|
|
cmd->subtype = AT_ReAddIndex;
|
|
tab->subcmds[AT_PASS_OLD_INDEX] =
|
|
lappend(tab->subcmds[AT_PASS_OLD_INDEX], cmd);
|
|
break;
|
|
case AT_AddConstraint:
|
|
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);
|
|
}
|
|
}
|
|
relation_close(rel, NoLock);
|
|
break;
|
|
}
|
|
default:
|
|
elog(ERROR, "unexpected statement type: %d",
|
|
(int) nodeTag(query->utilityStmt));
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
* ALTER TABLE OWNER
|
|
*/
|
|
static void
|
|
ATExecChangeOwner(Oid relationOid, int32 newOwnerSysId)
|
|
{
|
|
Relation target_rel;
|
|
Relation class_rel;
|
|
HeapTuple tuple;
|
|
Form_pg_class tuple_class;
|
|
|
|
/* Get exclusive lock till end of transaction on the target table */
|
|
/* Use relation_open here so that we work on indexes... */
|
|
target_rel = relation_open(relationOid, AccessExclusiveLock);
|
|
|
|
/* Get its pg_class tuple, too */
|
|
class_rel = heap_openr(RelationRelationName, RowExclusiveLock);
|
|
|
|
tuple = SearchSysCache(RELOID,
|
|
ObjectIdGetDatum(relationOid),
|
|
0, 0, 0);
|
|
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_INDEX:
|
|
case RELKIND_VIEW:
|
|
case RELKIND_SEQUENCE:
|
|
case RELKIND_TOASTVALUE:
|
|
/* ok to change owner */
|
|
break;
|
|
default:
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
|
|
errmsg("\"%s\" is not a table, TOAST table, index, view, or sequence",
|
|
NameStr(tuple_class->relname))));
|
|
}
|
|
|
|
/*
|
|
* 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 != newOwnerSysId)
|
|
{
|
|
Datum repl_val[Natts_pg_class];
|
|
char repl_null[Natts_pg_class];
|
|
char repl_repl[Natts_pg_class];
|
|
Acl *newAcl;
|
|
Datum aclDatum;
|
|
bool isNull;
|
|
HeapTuple newtuple;
|
|
|
|
/* Otherwise, check that we are the superuser */
|
|
if (!superuser())
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
|
|
errmsg("must be superuser to change owner")));
|
|
|
|
memset(repl_null, ' ', sizeof(repl_null));
|
|
memset(repl_repl, ' ', sizeof(repl_repl));
|
|
|
|
repl_repl[Anum_pg_class_relowner - 1] = 'r';
|
|
repl_val[Anum_pg_class_relowner - 1] = Int32GetDatum(newOwnerSysId);
|
|
|
|
/*
|
|
* 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, newOwnerSysId);
|
|
repl_repl[Anum_pg_class_relacl - 1] = 'r';
|
|
repl_val[Anum_pg_class_relacl - 1] = PointerGetDatum(newAcl);
|
|
}
|
|
|
|
newtuple = heap_modifytuple(tuple, class_rel, repl_val, repl_null, repl_repl);
|
|
|
|
simple_heap_update(class_rel, &newtuple->t_self, newtuple);
|
|
CatalogUpdateIndexes(class_rel, newtuple);
|
|
|
|
heap_freetuple(newtuple);
|
|
|
|
/*
|
|
* If we are operating on a table, also change the ownership of any
|
|
* indexes that belong to the table, as well as the table's toast
|
|
* table (if it has one)
|
|
*/
|
|
if (tuple_class->relkind == RELKIND_RELATION ||
|
|
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), newOwnerSysId);
|
|
|
|
list_free(index_oid_list);
|
|
}
|
|
|
|
if (tuple_class->relkind == RELKIND_RELATION)
|
|
{
|
|
/* If it has a toast table, recurse to change its ownership */
|
|
if (tuple_class->reltoastrelid != InvalidOid)
|
|
ATExecChangeOwner(tuple_class->reltoastrelid, newOwnerSysId);
|
|
}
|
|
}
|
|
|
|
ReleaseSysCache(tuple);
|
|
heap_close(class_rel, RowExclusiveLock);
|
|
relation_close(target_rel, NoLock);
|
|
}
|
|
|
|
/*
|
|
* 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)
|
|
{
|
|
Oid indexOid;
|
|
|
|
indexOid = get_relname_relid(indexName, rel->rd_rel->relnamespace);
|
|
|
|
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);
|
|
|
|
/* And do the work */
|
|
mark_index_clustered(rel, indexOid);
|
|
}
|
|
|
|
/*
|
|
* 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)
|
|
{
|
|
mark_index_clustered(rel, InvalidOid);
|
|
}
|
|
|
|
/*
|
|
* ALTER TABLE SET TABLESPACE
|
|
*/
|
|
static void
|
|
ATPrepSetTableSpace(AlteredTableInfo *tab, Relation rel, char *tablespacename)
|
|
{
|
|
Oid tablespaceId;
|
|
AclResult aclresult;
|
|
|
|
/*
|
|
* We do our own permission checking because we want to allow this on
|
|
* indexes.
|
|
*/
|
|
if (rel->rd_rel->relkind != RELKIND_RELATION &&
|
|
rel->rd_rel->relkind != RELKIND_INDEX)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
|
|
errmsg("\"%s\" is not a table or index",
|
|
RelationGetRelationName(rel))));
|
|
|
|
/* 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))));
|
|
|
|
/* Check that the tablespace exists */
|
|
tablespaceId = get_tablespace_oid(tablespacename);
|
|
if (!OidIsValid(tablespaceId))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_UNDEFINED_OBJECT),
|
|
errmsg("tablespace \"%s\" does not exist", tablespacename)));
|
|
|
|
/* 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),
|
|
errmsg("multiple SET TABLESPACE subcommands are not valid")));
|
|
tab->newTableSpace = tablespaceId;
|
|
}
|
|
|
|
/*
|
|
* 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)
|
|
{
|
|
Relation rel;
|
|
Oid oldTableSpace;
|
|
Oid reltoastrelid;
|
|
Oid reltoastidxid;
|
|
RelFileNode newrnode;
|
|
SMgrRelation dstrel;
|
|
Relation pg_class;
|
|
HeapTuple tuple;
|
|
Form_pg_class rd_rel;
|
|
|
|
rel = relation_open(tableOid, NoLock);
|
|
|
|
/*
|
|
* We can never allow moving of shared or nailed-in-cache relations,
|
|
* because we can't support changing their reltablespace values.
|
|
*/
|
|
if (rel->rd_rel->relisshared || rel->rd_isnailed)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
errmsg("cannot move system relation \"%s\"",
|
|
RelationGetRelationName(rel))));
|
|
|
|
/*
|
|
* Don't allow moving temp tables of other backends ... their
|
|
* local buffer manager is not going to cope.
|
|
*/
|
|
if (isOtherTempNamespace(RelationGetNamespace(rel)))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
errmsg("cannot move temporary tables of other sessions")));
|
|
|
|
/*
|
|
* No work if no change in tablespace.
|
|
*/
|
|
oldTableSpace = rel->rd_rel->reltablespace;
|
|
if (newTableSpace == oldTableSpace ||
|
|
(newTableSpace == MyDatabaseTableSpace && oldTableSpace == 0))
|
|
{
|
|
relation_close(rel, NoLock);
|
|
return;
|
|
}
|
|
|
|
reltoastrelid = rel->rd_rel->reltoastrelid;
|
|
reltoastidxid = rel->rd_rel->reltoastidxid;
|
|
|
|
/* Get a modifiable copy of the relation's pg_class row */
|
|
pg_class = heap_openr(RelationRelationName, RowExclusiveLock);
|
|
|
|
tuple = SearchSysCacheCopy(RELOID,
|
|
ObjectIdGetDatum(tableOid),
|
|
0, 0, 0);
|
|
if (!HeapTupleIsValid(tuple))
|
|
elog(ERROR, "cache lookup failed for relation %u", tableOid);
|
|
rd_rel = (Form_pg_class) GETSTRUCT(tuple);
|
|
|
|
/* create another storage file. Is it a little ugly ? */
|
|
/* NOTE: any conflict in relfilenode value will be caught here */
|
|
newrnode = rel->rd_node;
|
|
newrnode.spcNode = newTableSpace;
|
|
|
|
dstrel = smgropen(newrnode);
|
|
smgrcreate(dstrel, rel->rd_istemp, false);
|
|
|
|
/* copy relation data to the new physical file */
|
|
copy_relation_data(rel, dstrel);
|
|
|
|
/* schedule unlinking old physical file */
|
|
if (rel->rd_smgr == NULL)
|
|
rel->rd_smgr = smgropen(rel->rd_node);
|
|
smgrscheduleunlink(rel->rd_smgr, rel->rd_istemp);
|
|
rel->rd_smgr = NULL;
|
|
|
|
/*
|
|
* Now drop smgr references. The source was already dropped by
|
|
* smgrscheduleunlink.
|
|
*/
|
|
smgrclose(dstrel);
|
|
|
|
/* update the pg_class row */
|
|
rd_rel->reltablespace = (newTableSpace == MyDatabaseTableSpace) ? InvalidOid : newTableSpace;
|
|
simple_heap_update(pg_class, &tuple->t_self, tuple);
|
|
CatalogUpdateIndexes(pg_class, tuple);
|
|
|
|
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);
|
|
if (OidIsValid(reltoastidxid))
|
|
ATExecSetTableSpace(reltoastidxid, newTableSpace);
|
|
}
|
|
|
|
/*
|
|
* Copy data, block by block
|
|
*/
|
|
static void
|
|
copy_relation_data(Relation rel, SMgrRelation dst)
|
|
{
|
|
SMgrRelation src = rel->rd_smgr;
|
|
bool use_wal;
|
|
BlockNumber nblocks;
|
|
BlockNumber blkno;
|
|
char buf[BLCKSZ];
|
|
Page page = (Page) buf;
|
|
|
|
/*
|
|
* Since we copy the data 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 pages will get loaded into
|
|
* buffers while we are holding exclusive lock on the rel.
|
|
*/
|
|
FlushRelationBuffers(rel, 0);
|
|
|
|
/*
|
|
* We need to log the copied data in WAL iff WAL archiving is enabled
|
|
* AND it's not a temp rel.
|
|
*/
|
|
use_wal = XLogArchivingActive() && !rel->rd_istemp;
|
|
|
|
nblocks = RelationGetNumberOfBlocks(rel);
|
|
for (blkno = 0; blkno < nblocks; blkno++)
|
|
{
|
|
smgrread(src, blkno, buf);
|
|
|
|
/* XLOG stuff */
|
|
if (use_wal)
|
|
{
|
|
xl_heap_newpage xlrec;
|
|
XLogRecPtr recptr;
|
|
XLogRecData rdata[2];
|
|
|
|
/* NO ELOG(ERROR) from here till newpage op is logged */
|
|
START_CRIT_SECTION();
|
|
|
|
xlrec.node = dst->smgr_rnode;
|
|
xlrec.blkno = blkno;
|
|
|
|
rdata[0].buffer = InvalidBuffer;
|
|
rdata[0].data = (char *) &xlrec;
|
|
rdata[0].len = SizeOfHeapNewpage;
|
|
rdata[0].next = &(rdata[1]);
|
|
|
|
rdata[1].buffer = InvalidBuffer;
|
|
rdata[1].data = (char *) page;
|
|
rdata[1].len = BLCKSZ;
|
|
rdata[1].next = NULL;
|
|
|
|
recptr = XLogInsert(RM_HEAP_ID, XLOG_HEAP_NEWPAGE, rdata);
|
|
|
|
PageSetLSN(page, recptr);
|
|
PageSetTLI(page, ThisTimeLineID);
|
|
|
|
END_CRIT_SECTION();
|
|
}
|
|
|
|
/*
|
|
* 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.
|
|
*/
|
|
smgrwrite(dst, blkno, buf, true);
|
|
}
|
|
|
|
/*
|
|
* If the rel isn't temp, we must fsync it down to disk before it's
|
|
* safe to commit the transaction. (For a temp rel we don't care
|
|
* since the rel will be uninteresting 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 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 (!rel->rd_istemp)
|
|
smgrimmedsync(dst);
|
|
}
|
|
|
|
/*
|
|
* ALTER TABLE CREATE TOAST TABLE
|
|
*
|
|
* Note: this is also invoked from outside this module; in such cases we
|
|
* expect the caller to have verified that the relation is a table and we
|
|
* have all the right permissions. Callers expect this function
|
|
* to end with CommandCounterIncrement if it makes any changes.
|
|
*/
|
|
void
|
|
AlterTableCreateToastTable(Oid relOid, bool silent)
|
|
{
|
|
Relation rel;
|
|
HeapTuple reltup;
|
|
TupleDesc tupdesc;
|
|
bool shared_relation;
|
|
Relation class_rel;
|
|
Oid toast_relid;
|
|
Oid toast_idxid;
|
|
char toast_relname[NAMEDATALEN];
|
|
char toast_idxname[NAMEDATALEN];
|
|
IndexInfo *indexInfo;
|
|
Oid classObjectId[2];
|
|
ObjectAddress baseobject,
|
|
toastobject;
|
|
|
|
/*
|
|
* Grab an exclusive lock on the target table, which we will NOT
|
|
* release until end of transaction. (This is probably redundant
|
|
* in all present uses...)
|
|
*/
|
|
rel = heap_open(relOid, AccessExclusiveLock);
|
|
|
|
/*
|
|
* Toast table is shared if and only if its parent is.
|
|
*
|
|
* We cannot allow toasting a shared relation after initdb (because
|
|
* there's no way to mark it toasted in other databases' pg_class).
|
|
* Unfortunately we can't distinguish initdb from a manually started
|
|
* standalone backend (toasting happens after the bootstrap phase,
|
|
* so checking IsBootstrapProcessingMode() won't work). However, we can
|
|
* at least prevent this mistake under normal multi-user operation.
|
|
*/
|
|
shared_relation = rel->rd_rel->relisshared;
|
|
if (shared_relation && IsUnderPostmaster)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
|
|
errmsg("shared tables cannot be toasted after initdb")));
|
|
|
|
/*
|
|
* Is it already toasted?
|
|
*/
|
|
if (rel->rd_rel->reltoastrelid != InvalidOid)
|
|
{
|
|
if (silent)
|
|
{
|
|
heap_close(rel, NoLock);
|
|
return;
|
|
}
|
|
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
|
|
errmsg("table \"%s\" already has a TOAST table",
|
|
RelationGetRelationName(rel))));
|
|
}
|
|
|
|
/*
|
|
* Check to see whether the table actually needs a TOAST table.
|
|
*/
|
|
if (!needs_toast_table(rel))
|
|
{
|
|
if (silent)
|
|
{
|
|
heap_close(rel, NoLock);
|
|
return;
|
|
}
|
|
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
|
|
errmsg("table \"%s\" does not need a TOAST table",
|
|
RelationGetRelationName(rel))));
|
|
}
|
|
|
|
/*
|
|
* Create the toast table and its index
|
|
*/
|
|
snprintf(toast_relname, sizeof(toast_relname),
|
|
"pg_toast_%u", relOid);
|
|
snprintf(toast_idxname, sizeof(toast_idxname),
|
|
"pg_toast_%u_index", relOid);
|
|
|
|
/* this is pretty painful... need a tuple descriptor */
|
|
tupdesc = CreateTemplateTupleDesc(3, false);
|
|
TupleDescInitEntry(tupdesc, (AttrNumber) 1,
|
|
"chunk_id",
|
|
OIDOID,
|
|
-1, 0);
|
|
TupleDescInitEntry(tupdesc, (AttrNumber) 2,
|
|
"chunk_seq",
|
|
INT4OID,
|
|
-1, 0);
|
|
TupleDescInitEntry(tupdesc, (AttrNumber) 3,
|
|
"chunk_data",
|
|
BYTEAOID,
|
|
-1, 0);
|
|
|
|
/*
|
|
* Ensure that the toast table doesn't itself get toasted, or we'll be
|
|
* toast :-(. This is essential for chunk_data because type bytea is
|
|
* toastable; hit the other two just to be sure.
|
|
*/
|
|
tupdesc->attrs[0]->attstorage = 'p';
|
|
tupdesc->attrs[1]->attstorage = 'p';
|
|
tupdesc->attrs[2]->attstorage = 'p';
|
|
|
|
/*
|
|
* Note: the toast relation is placed in the regular pg_toast
|
|
* namespace even if its master relation is a temp table. There
|
|
* cannot be any naming collision, and the toast rel will be destroyed
|
|
* when its master is, so there's no need to handle the toast rel as
|
|
* temp.
|
|
*/
|
|
toast_relid = heap_create_with_catalog(toast_relname,
|
|
PG_TOAST_NAMESPACE,
|
|
rel->rd_rel->reltablespace,
|
|
tupdesc,
|
|
RELKIND_TOASTVALUE,
|
|
shared_relation,
|
|
true,
|
|
0,
|
|
ONCOMMIT_NOOP,
|
|
true);
|
|
|
|
/* make the toast relation visible, else index creation will fail */
|
|
CommandCounterIncrement();
|
|
|
|
/*
|
|
* Create unique index on chunk_id, chunk_seq.
|
|
*
|
|
* NOTE: the normal TOAST access routines could actually function with a
|
|
* single-column index on chunk_id only. However, the slice access
|
|
* routines use both columns for faster access to an individual chunk.
|
|
* In addition, we want it to be unique as a check against the
|
|
* possibility of duplicate TOAST chunk OIDs. The index might also be
|
|
* a little more efficient this way, since btree isn't all that happy
|
|
* with large numbers of equal keys.
|
|
*/
|
|
|
|
indexInfo = makeNode(IndexInfo);
|
|
indexInfo->ii_NumIndexAttrs = 2;
|
|
indexInfo->ii_KeyAttrNumbers[0] = 1;
|
|
indexInfo->ii_KeyAttrNumbers[1] = 2;
|
|
indexInfo->ii_Expressions = NIL;
|
|
indexInfo->ii_ExpressionsState = NIL;
|
|
indexInfo->ii_Predicate = NIL;
|
|
indexInfo->ii_PredicateState = NIL;
|
|
indexInfo->ii_Unique = true;
|
|
|
|
classObjectId[0] = OID_BTREE_OPS_OID;
|
|
classObjectId[1] = INT4_BTREE_OPS_OID;
|
|
|
|
toast_idxid = index_create(toast_relid, toast_idxname, indexInfo,
|
|
BTREE_AM_OID,
|
|
rel->rd_rel->reltablespace,
|
|
classObjectId,
|
|
true, false, true, false);
|
|
|
|
/*
|
|
* Update toast rel's pg_class entry to show that it has an index. The
|
|
* index OID is stored into the reltoastidxid field for easy access by
|
|
* the tuple toaster.
|
|
*/
|
|
setRelhasindex(toast_relid, true, true, toast_idxid);
|
|
|
|
/*
|
|
* Store the toast table's OID in the parent relation's pg_class row
|
|
*/
|
|
class_rel = heap_openr(RelationRelationName, RowExclusiveLock);
|
|
|
|
reltup = SearchSysCacheCopy(RELOID,
|
|
ObjectIdGetDatum(relOid),
|
|
0, 0, 0);
|
|
if (!HeapTupleIsValid(reltup))
|
|
elog(ERROR, "cache lookup failed for relation %u", relOid);
|
|
|
|
((Form_pg_class) GETSTRUCT(reltup))->reltoastrelid = toast_relid;
|
|
|
|
simple_heap_update(class_rel, &reltup->t_self, reltup);
|
|
|
|
/* Keep catalog indexes current */
|
|
CatalogUpdateIndexes(class_rel, reltup);
|
|
|
|
heap_freetuple(reltup);
|
|
|
|
heap_close(class_rel, RowExclusiveLock);
|
|
|
|
/*
|
|
* Register dependency from the toast table to the master, so that the
|
|
* toast table will be deleted if the master is.
|
|
*/
|
|
baseobject.classId = RelOid_pg_class;
|
|
baseobject.objectId = relOid;
|
|
baseobject.objectSubId = 0;
|
|
toastobject.classId = RelOid_pg_class;
|
|
toastobject.objectId = toast_relid;
|
|
toastobject.objectSubId = 0;
|
|
|
|
recordDependencyOn(&toastobject, &baseobject, DEPENDENCY_INTERNAL);
|
|
|
|
/*
|
|
* Clean up and make changes visible
|
|
*/
|
|
heap_close(rel, NoLock);
|
|
|
|
CommandCounterIncrement();
|
|
}
|
|
|
|
/*
|
|
* Check to see whether the table needs a TOAST table. It does only if
|
|
* (1) there are any toastable attributes, and (2) the maximum length
|
|
* of a tuple could exceed TOAST_TUPLE_THRESHOLD. (We don't want to
|
|
* create a toast table for something like "f1 varchar(20)".)
|
|
*/
|
|
static bool
|
|
needs_toast_table(Relation rel)
|
|
{
|
|
int32 data_length = 0;
|
|
bool maxlength_unknown = false;
|
|
bool has_toastable_attrs = false;
|
|
TupleDesc tupdesc;
|
|
Form_pg_attribute *att;
|
|
int32 tuple_length;
|
|
int i;
|
|
|
|
tupdesc = rel->rd_att;
|
|
att = tupdesc->attrs;
|
|
|
|
for (i = 0; i < tupdesc->natts; i++)
|
|
{
|
|
data_length = att_align(data_length, att[i]->attalign);
|
|
if (att[i]->attlen > 0)
|
|
{
|
|
/* Fixed-length types are never toastable */
|
|
data_length += att[i]->attlen;
|
|
}
|
|
else
|
|
{
|
|
int32 maxlen = type_maximum_size(att[i]->atttypid,
|
|
att[i]->atttypmod);
|
|
|
|
if (maxlen < 0)
|
|
maxlength_unknown = true;
|
|
else
|
|
data_length += maxlen;
|
|
if (att[i]->attstorage != 'p')
|
|
has_toastable_attrs = true;
|
|
}
|
|
}
|
|
if (!has_toastable_attrs)
|
|
return false; /* nothing to toast? */
|
|
if (maxlength_unknown)
|
|
return true; /* any unlimited-length attrs? */
|
|
tuple_length = MAXALIGN(offsetof(HeapTupleHeaderData, t_bits) +
|
|
BITMAPLEN(tupdesc->natts)) +
|
|
MAXALIGN(data_length);
|
|
return (tuple_length > TOAST_TUPLE_THRESHOLD);
|
|
}
|
|
|
|
|
|
/*
|
|
* 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)
|
|
{
|
|
OnCommitItem *oc;
|
|
MemoryContext oldcxt;
|
|
|
|
/*
|
|
* 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_xid = GetCurrentTransactionId();
|
|
oc->deleting_xid = InvalidTransactionId;
|
|
|
|
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)
|
|
{
|
|
OnCommitItem *oc = (OnCommitItem *) lfirst(l);
|
|
|
|
if (oc->relid == relid)
|
|
{
|
|
oc->deleting_xid = GetCurrentTransactionId();
|
|
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)
|
|
{
|
|
TransactionId xid = GetCurrentTransactionId();
|
|
ListCell *l;
|
|
|
|
foreach(l, on_commits)
|
|
{
|
|
OnCommitItem *oc = (OnCommitItem *) lfirst(l);
|
|
|
|
/* Ignore entry if already dropped in this xact */
|
|
if (oc->deleting_xid == xid)
|
|
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:
|
|
heap_truncate(oc->relid);
|
|
CommandCounterIncrement(); /* XXX needed? */
|
|
break;
|
|
case ONCOMMIT_DROP:
|
|
{
|
|
ObjectAddress object;
|
|
|
|
object.classId = RelOid_pg_class;
|
|
object.objectId = oc->relid;
|
|
object.objectSubId = 0;
|
|
performDeletion(&object, DROP_CASCADE);
|
|
|
|
/*
|
|
* Note that table deletion will call
|
|
* remove_on_commit_action, so the entry should get
|
|
* marked as deleted.
|
|
*/
|
|
Assert(oc->deleting_xid == xid);
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* 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, TransactionId xid)
|
|
{
|
|
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 ? TransactionIdEquals(oc->deleting_xid, xid) :
|
|
TransactionIdEquals(oc->creating_xid, xid))
|
|
{
|
|
/* 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_xid = InvalidTransactionId;
|
|
oc->deleting_xid = InvalidTransactionId;
|
|
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
|
|
* subtransaction. During subcommit, just relabel entries marked during
|
|
* this subtransaction as being the parent's responsibility.
|
|
*/
|
|
void
|
|
AtEOSubXact_on_commit_actions(bool isCommit, TransactionId childXid,
|
|
TransactionId parentXid)
|
|
{
|
|
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 && TransactionIdEquals(oc->creating_xid, childXid))
|
|
{
|
|
/* 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 (TransactionIdEquals(oc->creating_xid, childXid))
|
|
oc->creating_xid = parentXid;
|
|
if (TransactionIdEquals(oc->deleting_xid, childXid))
|
|
oc->deleting_xid = isCommit ? parentXid : InvalidTransactionId;
|
|
prev_item = cur_item;
|
|
cur_item = lnext(prev_item);
|
|
}
|
|
}
|
|
}
|