Add operator strategy and comparison-value datatype fields to ScanKey.

Remove the 'strategy map' code, which was a large amount of mechanism
that no longer had any use except reverse-mapping from procedure OID to
strategy number.  Passing the strategy number to the index AM in the
first place is simpler and faster.
This is a preliminary step in planned support for cross-datatype index
operations.  I'm committing it now since the ScanKeyEntryInitialize()
API change touches quite a lot of files, and I want to commit those
changes before the tree drifts under me.

src/backend/optimizer/util/plancat.c

@@ -9,7 +9,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/optimizer/util/plancat.c,v 1.87 2003/08/04 02:40:01 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/optimizer/util/plancat.c,v 1.88 2003/11/09 21:30:37 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -23,6 +23,7 @@
 #include "catalog/pg_amop.h"
 #include "catalog/pg_inherits.h"
 #include "catalog/pg_index.h"
+#include "catalog/pg_type.h"
 #include "nodes/makefuncs.h"
 #include "optimizer/clauses.h"
 #include "optimizer/plancat.h"
@@ -328,11 +329,10 @@ find_inheritance_children(Oid inhparent)
 	if (!has_subclass(inhparent))
 		return NIL;
 
-	ScanKeyEntryInitialize(&key[0],
-						   (bits16) 0x0,
-						   (AttrNumber) Anum_pg_inherits_inhparent,
-						   (RegProcedure) F_OIDEQ,
-						   ObjectIdGetDatum(inhparent));
+	ScanKeyEntryInitialize(&key[0], 0,
+						   Anum_pg_inherits_inhparent,
+						   BTEqualStrategyNumber, F_OIDEQ,
+						   ObjectIdGetDatum(inhparent), OIDOID);
 	relation = heap_openr(InheritsRelationName, AccessShareLock);
 	scan = heap_beginscan(relation, SnapshotNow, 1, key);
 	while ((inheritsTuple = heap_getnext(scan, ForwardScanDirection)) != NULL)