diff options
Diffstat (limited to 'src/backend/optimizer/util/plancat.c')
| -rw-r--r-- | src/backend/optimizer/util/plancat.c | 79 |
1 files changed, 1 insertions, 78 deletions
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c index 6225bc14fff..0479e93ec82 100644 --- a/src/backend/optimizer/util/plancat.c +++ b/src/backend/optimizer/util/plancat.c @@ -9,7 +9,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/optimizer/util/plancat.c,v 1.156 2009/03/05 23:06:45 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/optimizer/util/plancat.c,v 1.157 2009/05/12 00:56:05 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -22,7 +22,6 @@ #include "access/sysattr.h" #include "access/transam.h" #include "catalog/catalog.h" -#include "catalog/pg_inherits.h" #include "miscadmin.h" #include "nodes/makefuncs.h" #include "nodes/nodeFuncs.h" @@ -35,12 +34,9 @@ #include "parser/parsetree.h" #include "rewrite/rewriteManip.h" #include "storage/bufmgr.h" -#include "utils/fmgroids.h" #include "utils/lsyscache.h" #include "utils/rel.h" #include "utils/snapmgr.h" -#include "utils/syscache.h" -#include "utils/tqual.h" /* GUC parameter */ @@ -851,79 +847,6 @@ join_selectivity(PlannerInfo *root, } /* - * find_inheritance_children - * - * Returns a list containing the OIDs of all relations which - * inherit *directly* from the relation with OID 'inhparent'. - * - * XXX might be a good idea to create an index on pg_inherits' inhparent - * field, so that we can use an indexscan instead of sequential scan here. - * However, in typical databases pg_inherits won't have enough entries to - * justify an indexscan... - */ -List * -find_inheritance_children(Oid inhparent) -{ - List *list = NIL; - Relation relation; - HeapScanDesc scan; - HeapTuple inheritsTuple; - Oid inhrelid; - ScanKeyData key[1]; - - /* - * Can skip the scan if pg_class shows the relation has never had a - * subclass. - */ - if (!has_subclass(inhparent)) - return NIL; - - ScanKeyInit(&key[0], - Anum_pg_inherits_inhparent, - BTEqualStrategyNumber, F_OIDEQ, - ObjectIdGetDatum(inhparent)); - relation = heap_open(InheritsRelationId, AccessShareLock); - scan = heap_beginscan(relation, SnapshotNow, 1, key); - while ((inheritsTuple = heap_getnext(scan, ForwardScanDirection)) != NULL) - { - inhrelid = ((Form_pg_inherits) GETSTRUCT(inheritsTuple))->inhrelid; - list = lappend_oid(list, inhrelid); - } - heap_endscan(scan); - heap_close(relation, AccessShareLock); - return list; -} - -/* - * has_subclass - * - * In the current implementation, has_subclass returns whether a - * particular class *might* have a subclass. It will not return the - * correct result if a class had a subclass which was later dropped. - * This is because relhassubclass in pg_class is not updated when a - * subclass is dropped, primarily because of concurrency concerns. - * - * Currently has_subclass is only used as an efficiency hack to skip - * unnecessary inheritance searches, so this is OK. - */ -bool -has_subclass(Oid relationId) -{ - HeapTuple tuple; - bool result; - - tuple = SearchSysCache(RELOID, - ObjectIdGetDatum(relationId), - 0, 0, 0); - if (!HeapTupleIsValid(tuple)) - elog(ERROR, "cache lookup failed for relation %u", relationId); - - result = ((Form_pg_class) GETSTRUCT(tuple))->relhassubclass; - ReleaseSysCache(tuple); - return result; -} - -/* * has_unique_index * * Detect whether there is a unique index on the specified attribute |