Change search for default operator classes so that it examines all opclasses

regardless of the current schema search path.  Since CREATE OPERATOR CLASS
only allows one default opclass per datatype regardless of schemas, this
should have minimal impact, and it fixes problems with failure to find a
desired opclass while restoring dump files.  Per discussion at
http://archives.postgresql.org/pgsql-hackers/2006-02/msg00284.php.
Remove now-redundant-or-unused code in typcache.c and namespace.c,
and backpatch as far as 8.0.

1 files changed, 7 insertions, 94 deletions

diff --git a/src/backend/utils/cache/typcache.c b/src/backend/utils/cache/typcache.c
index 16025e2c6ff..092910f07bd 100644
--- a/src/backend/utils/cache/typcache.c
+++ b/src/backend/utils/cache/typcache.c
@@ -36,23 +36,19 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/cache/typcache.c,v 1.15.2.2 2006/01/17 17:33:21 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/cache/typcache.c,v 1.15.2.3 2006/02/10 19:01:22 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
 #include "postgres.h"
 
-#include "access/genam.h"
 #include "access/heapam.h"
 #include "access/hash.h"
 #include "access/nbtree.h"
-#include "catalog/indexing.h"
-#include "catalog/pg_am.h"
-#include "catalog/pg_opclass.h"
-#include "parser/parse_coerce.h"
+#include "catalog/pg_type.h"
+#include "commands/defrem.h"
 #include "utils/builtins.h"
 #include "utils/catcache.h"
-#include "utils/fmgroids.h"
 #include "utils/hsearch.h"
 #include "utils/lsyscache.h"
 #include "utils/syscache.h"
@@ -92,9 +88,6 @@ static int32 RecordCacheArrayLen = 0;	/* allocated length of array */
 static int32 NextRecordTypmod = 0;		/* number of entries used */
 
 
-static Oid	lookup_default_opclass(Oid type_id, Oid am_id);
-
-
 /*
  * lookup_type_cache
  *
@@ -177,14 +170,14 @@ lookup_type_cache(Oid type_id, int flags)
 				  TYPECACHE_EQ_OPR_FINFO | TYPECACHE_CMP_PROC_FINFO)) &&
 		typentry->btree_opc == InvalidOid)
 	{
-		typentry->btree_opc = lookup_default_opclass(type_id,
-													 BTREE_AM_OID);
+		typentry->btree_opc = GetDefaultOpClass(type_id,
+												BTREE_AM_OID);
 		/* Only care about hash opclass if no btree opclass... */
 		if (typentry->btree_opc == InvalidOid)
 		{
 			if (typentry->hash_opc == InvalidOid)
-				typentry->hash_opc = lookup_default_opclass(type_id,
-															HASH_AM_OID);
+				typentry->hash_opc = GetDefaultOpClass(type_id,
+													   HASH_AM_OID);
 		}
 		else
 		{
@@ -290,86 +283,6 @@ lookup_type_cache(Oid type_id, int flags)
 }
 
 /*
- * lookup_default_opclass
- *
- * Given the OIDs of a datatype and an access method, find the default
- * operator class, if any.	Returns InvalidOid if there is none.
- */
-static Oid
-lookup_default_opclass(Oid type_id, Oid am_id)
-{
-	int			nexact = 0;
-	int			ncompatible = 0;
-	Oid			exactOid = InvalidOid;
-	Oid			compatibleOid = InvalidOid;
-	Relation	rel;
-	ScanKeyData skey[1];
-	SysScanDesc scan;
-	HeapTuple	tup;
-
-	/* If it's a domain, look at the base type instead */
-	type_id = getBaseType(type_id);
-
-	/*
-	 * We scan through all the opclasses available for the access method,
-	 * looking for one that is marked default and matches the target type
-	 * (either exactly or binary-compatibly, but prefer an exact match).
-	 *
-	 * We could find more than one binary-compatible match, in which case we
-	 * require the user to specify which one he wants.	If we find more than
-	 * one exact match, then someone put bogus entries in pg_opclass.
-	 *
-	 * This is the same logic as GetDefaultOpClass() in indexcmds.c, except
-	 * that we consider all opclasses, regardless of the current search path.
-	 */
-	rel = heap_open(OperatorClassRelationId, AccessShareLock);
-
-	ScanKeyInit(&skey[0],
-				Anum_pg_opclass_opcamid,
-				BTEqualStrategyNumber, F_OIDEQ,
-				ObjectIdGetDatum(am_id));
-
-	scan = systable_beginscan(rel, OpclassAmNameNspIndexId, true,
-							  SnapshotNow, 1, skey);
-
-	while (HeapTupleIsValid(tup = systable_getnext(scan)))
-	{
-		Form_pg_opclass opclass = (Form_pg_opclass) GETSTRUCT(tup);
-
-		if (opclass->opcdefault)
-		{
-			if (opclass->opcintype == type_id)
-			{
-				nexact++;
-				exactOid = HeapTupleGetOid(tup);
-			}
-			else if (IsBinaryCoercible(type_id, opclass->opcintype))
-			{
-				ncompatible++;
-				compatibleOid = HeapTupleGetOid(tup);
-			}
-		}
-	}
-
-	systable_endscan(scan);
-
-	heap_close(rel, AccessShareLock);
-
-	if (nexact == 1)
-		return exactOid;
-	if (nexact != 0)
-		ereport(ERROR,
-				(errcode(ERRCODE_DUPLICATE_OBJECT),
-		errmsg("there are multiple default operator classes for data type %s",
-			   format_type_be(type_id))));
-	if (ncompatible == 1)
-		return compatibleOid;
-
-	return InvalidOid;
-}
-
-
-/*
  * lookup_rowtype_tupdesc
  *
  * Given a typeid/typmod that should describe a known composite type,