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Fix performance problems with pg_index lookups (see, for example,

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discussion of 5/19/00).  pg_index is now searched for indexes of a
relation using an indexscan.  Moreover, this is done once and cached
in the relcache entry for the relation, in the form of a list of OIDs
for the indexes.  This list is used by the parser and executor to drive
lookups in the pg_index syscache when they want to know the properties
of the indexes.  Net result: index information will be fully cached
for repetitive operations such as inserts.
This commit is contained in:
Tom Lane
2000-06-17 21:49:04 +00:00
parent 9cf80f2f55
commit d03a933ec5
13 changed files with 389 additions and 525 deletions
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59
src/backend/parser/analyze.c
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@ -6,7 +6,7 @@
* Portions Copyright (c) 1996-2000, PostgreSQL, Inc
* Portions Copyright (c) 1994, Regents of the University of California
*
* $Id: analyze.c,v 1.147 2000/06/12 19:40:40 momjian Exp $
* $Id: analyze.c,v 1.148 2000/06/17 21:48:40 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -27,6 +27,8 @@
#include "parser/parse_type.h"
#include "utils/builtins.h"
#include "utils/fmgroids.h"
#include "utils/relcache.h"
#include "utils/syscache.h"
void CheckSelectForUpdate(Query *qry); /* no points for style... */
@ -2003,13 +2005,9 @@ transformFkeyGetPrimaryKey(FkConstraint *fkconstraint)
{
Relation pkrel;
Form_pg_attribute *pkrel_attrs;
Relation indexRd;
HeapScanDesc indexSd;
ScanKeyData key;
HeapTuple indexTup;
List *indexoidlist,
*indexoidscan;
Form_pg_index indexStruct = NULL;
Ident *pkattr;
int pkattno;
int i;
/* ----------
@ -2023,37 +2021,37 @@ transformFkeyGetPrimaryKey(FkConstraint *fkconstraint)
pkrel_attrs = pkrel->rd_att->attrs;
/* ----------
* Open pg_index and begin a scan for all indices defined on
* the referenced table
* 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).
* ----------
*/
indexRd = heap_openr(IndexRelationName, AccessShareLock);
ScanKeyEntryInitialize(&key, 0, Anum_pg_index_indrelid,
F_OIDEQ,
ObjectIdGetDatum(pkrel->rd_id));
indexSd = heap_beginscan(indexRd, /* scan desc */
false, /* scan backward flag */
SnapshotNow, /* NOW snapshot */
1, /* number scan keys */
&key); /* scan keys */
indexoidlist = RelationGetIndexList(pkrel);
/* ----------
* Fetch the index with indisprimary == true
* ----------
*/
while (HeapTupleIsValid(indexTup = heap_getnext(indexSd, 0)))
foreach(indexoidscan, indexoidlist)
{
indexStruct = (Form_pg_index) GETSTRUCT(indexTup);
Oid indexoid = lfirsti(indexoidscan);
HeapTuple indexTuple;
indexTuple = SearchSysCacheTuple(INDEXRELID,
ObjectIdGetDatum(indexoid),
0, 0, 0);
if (!HeapTupleIsValid(indexTuple))
elog(ERROR, "transformFkeyGetPrimaryKey: index %u not found",
indexoid);
indexStruct = (Form_pg_index) GETSTRUCT(indexTuple);
if (indexStruct->indisprimary)
break;
indexStruct = NULL;
}
freeList(indexoidlist);
/* ----------
* Check that we found it
* ----------
*/
if (!HeapTupleIsValid(indexTup))
if (indexStruct == NULL)
elog(ERROR, "PRIMARY KEY for referenced table \"%s\" not found",
fkconstraint->pktable_name);
@ -2064,8 +2062,9 @@ transformFkeyGetPrimaryKey(FkConstraint *fkconstraint)
*/
for (i = 0; i < INDEX_MAX_KEYS && indexStruct->indkey[i] != 0; i++)
{
pkattno = indexStruct->indkey[i];
pkattr = (Ident *) makeNode(Ident);
int pkattno = indexStruct->indkey[i];
Ident *pkattr = makeNode(Ident);
pkattr->name = nameout(&(pkrel_attrs[pkattno - 1]->attname));
pkattr->indirection = NIL;
pkattr->isRel = false;
@ -2073,12 +2072,6 @@ transformFkeyGetPrimaryKey(FkConstraint *fkconstraint)
fkconstraint->pk_attrs = lappend(fkconstraint->pk_attrs, pkattr);
}
/* ----------
* End index scan and close relations
* ----------
*/
heap_endscan(indexSd);
heap_close(indexRd, AccessShareLock);
heap_close(pkrel, AccessShareLock);
}