rewriteRemove.c File Reference

#include "postgres.h"
#include "access/genam.h"
#include "access/htup_details.h"
#include "access/table.h"
#include "catalog/catalog.h"
#include "catalog/indexing.h"
#include "catalog/pg_rewrite.h"
#include "miscadmin.h"
#include "rewrite/rewriteRemove.h"
#include "utils/fmgroids.h"
#include "utils/inval.h"
#include "utils/rel.h"

Include dependency graph for rewriteRemove.c:

Go to the source code of this file.

Functions
void	RemoveRewriteRuleById (Oid ruleOid)

Function Documentation

RemoveRewriteRuleById()

void RemoveRewriteRuleById

(

Oid

ruleOid

)

Definition at line 33 of file rewriteRemove.c.

{
    Relation    RewriteRelation;
    ScanKeyData skey[1];
    SysScanDesc rcscan;
    Relation    event_relation;
    HeapTuple   tuple;
    Oid         eventRelationOid;
 
    /*
     * Open the pg_rewrite relation.
     */
    RewriteRelation = table_open(RewriteRelationId, RowExclusiveLock);
 
    /*
     * Find the tuple for the target rule.
     */
    ScanKeyInit(&skey[0],
                Anum_pg_rewrite_oid,
                BTEqualStrategyNumber, F_OIDEQ,
                ObjectIdGetDatum(ruleOid));
 
    rcscan = systable_beginscan(RewriteRelation, RewriteOidIndexId, true,
                                NULL, 1, skey);
 
    tuple = systable_getnext(rcscan);
 
    if (!HeapTupleIsValid(tuple))
        elog(ERROR, "could not find tuple for rule %u", ruleOid);
 
    /*
     * We had better grab AccessExclusiveLock to ensure that no queries are
     * going on that might depend on this rule.  (Note: a weaker lock would
     * suffice if it's not an ON SELECT rule.)
     */
    eventRelationOid = ((Form_pg_rewrite) GETSTRUCT(tuple))->ev_class;
    event_relation = table_open(eventRelationOid, AccessExclusiveLock);
 
    if (!allowSystemTableMods && IsSystemRelation(event_relation))
        ereport(ERROR,
                (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
                 errmsg("permission denied: \"%s\" is a system catalog",
                        RelationGetRelationName(event_relation))));
 
    /*
     * Now delete the pg_rewrite tuple for the rule
     */
    CatalogTupleDelete(RewriteRelation, &tuple->t_self);
 
    systable_endscan(rcscan);
 
    table_close(RewriteRelation, RowExclusiveLock);
 
    /*
     * Issue shared-inval notice to force all backends (including me!) to
     * update relcache entries with the new rule set.
     */
    CacheInvalidateRelcache(event_relation);
 
    /* Close rel, but keep lock till commit... */
    table_close(event_relation, NoLock);
}

References AccessExclusiveLock, allowSystemTableMods, BTEqualStrategyNumber, CacheInvalidateRelcache(), CatalogTupleDelete(), elog, ereport, errcode(), errmsg(), ERROR, GETSTRUCT(), HeapTupleIsValid, IsSystemRelation(), NoLock, ObjectIdGetDatum(), RelationGetRelationName, RowExclusiveLock, ScanKeyInit(), systable_beginscan(), systable_endscan(), systable_getnext(), HeapTupleData::t_self, table_close(), and table_open().

Referenced by doDeletion().