Add a back-link from IndexOptInfo structs to their parent RelOptInfo

structs.  There are many places in the planner where we were passing
both a rel and an index to subroutines, and now need only pass the
index struct.  Notationally simpler, and perhaps a tad faster.

src/backend/optimizer/path/costsize.c

@@ -49,7 +49,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/optimizer/path/costsize.c,v 1.138 2005/03/06 22:15:04 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/optimizer/path/costsize.c,v 1.139 2005/03/27 06:29:35 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -227,7 +227,6 @@ cost_nonsequential_access(double relpages)
  *	  but here we consider the cost of just one pass.
  *
  * 'root' is the query root
- * 'baserel' is the base relation the index is for
  * 'index' is the index to be used
  * 'indexQuals' is the list of applicable qual clauses (implicit AND semantics)
  * 'is_injoin' is T if we are considering using the index scan as the inside
@@ -243,11 +242,11 @@ cost_nonsequential_access(double relpages)
  */
 void
 cost_index(Path *path, Query *root,
-		   RelOptInfo *baserel,
 		   IndexOptInfo *index,
 		   List *indexQuals,
 		   bool is_injoin)
 {
+	RelOptInfo *baserel = index->rel;
 	Cost		startup_cost = 0;
 	Cost		run_cost = 0;
 	Cost		indexStartupCost;

src/backend/optimizer/path/orindxpath.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/optimizer/path/orindxpath.c,v 1.66 2005/03/26 23:29:17 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/optimizer/path/orindxpath.c,v 1.67 2005/03/27 06:29:36 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -383,7 +383,7 @@ best_or_subclause_index(Query *root,
 		}
 
 		/* Collect index clauses usable with this index */
-		indexclauses = group_clauses_by_indexkey_for_or(rel, index, subclause);
+		indexclauses = group_clauses_by_indexkey_for_or(index, subclause);
 
 		/*
 		 * Ignore index if it doesn't match the subclause at all; except
@@ -398,9 +398,9 @@ best_or_subclause_index(Query *root,
 			continue;
 
 		/* Convert clauses to indexquals the executor can handle */
-		indexquals = expand_indexqual_conditions(rel, index, indexclauses);
+		indexquals = expand_indexqual_conditions(index, indexclauses);
 
-		cost_index(&subclause_path, root, rel, index, indexquals, false);
+		cost_index(&subclause_path, root, index, indexquals, false);
 
 		if (!found || subclause_path.total_cost < *retTotalCost)
 		{

src/backend/optimizer/path/pathkeys.c

@@ -11,7 +11,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/optimizer/path/pathkeys.c,v 1.64 2005/01/23 02:21:26 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/optimizer/path/pathkeys.c,v 1.65 2005/03/27 06:29:36 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -648,7 +648,6 @@ get_cheapest_fractional_path_for_pathkeys(List *paths,
  */
 List *
 build_index_pathkeys(Query *root,
-					 RelOptInfo *rel,
 					 IndexOptInfo *index,
 					 ScanDirection scandir)
 {
@@ -675,7 +674,8 @@ build_index_pathkeys(Query *root,
 		if (*indexkeys != 0)
 		{
 			/* simple index column */
-			indexkey = (Node *) find_indexkey_var(root, rel, *indexkeys);
+			indexkey = (Node *) find_indexkey_var(root, index->rel,
+												  *indexkeys);
 		}
 		else
 		{

src/backend/optimizer/plan/createplan.c

@@ -10,7 +10,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/optimizer/plan/createplan.c,v 1.176 2005/03/10 23:21:22 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/optimizer/plan/createplan.c,v 1.177 2005/03/27 06:29:38 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -65,16 +65,13 @@ static void fix_indxqual_references(List *indexquals, IndexPath *index_path,
 						List **indxstrategy,
 						List **indxsubtype,
 						List **indxlossy);
-static void fix_indxqual_sublist(List *indexqual,
-					 Relids baserelids, int baserelid,
-					 IndexOptInfo *index,
+static void fix_indxqual_sublist(List *indexqual, IndexOptInfo *index,
 					 List **fixed_quals,
 					 List **strategy,
 					 List **subtype,
 					 List **lossy);
-static Node *fix_indxqual_operand(Node *node, int baserelid,
-					 IndexOptInfo *index,
-					 Oid *opclass);
+static Node *fix_indxqual_operand(Node *node, IndexOptInfo *index,
+								  Oid *opclass);
 static List *get_switched_clauses(List *clauses, Relids outerrelids);
 static List *order_qual_clauses(Query *root, List *clauses);
 static void copy_path_costsize(Plan *dest, Path *src);
@@ -1179,8 +1176,6 @@ fix_indxqual_references(List *indexquals, IndexPath *index_path,
 						List **indxsubtype,
 						List **indxlossy)
 {
-	Relids		baserelids = index_path->path.parent->relids;
-	int			baserelid = index_path->path.parent->relid;
 	List	   *index_info = index_path->indexinfo;
 	ListCell   *iq,
 			   *ii;
@@ -1198,7 +1193,7 @@ fix_indxqual_references(List *indexquals, IndexPath *index_path,
 		List	   *subtype;
 		List	   *lossy;
 
-		fix_indxqual_sublist(indexqual, baserelids, baserelid, index,
+		fix_indxqual_sublist(indexqual, index,
 							 &fixed_qual, &strategy, &subtype, &lossy);
 		*fixed_indexquals = lappend(*fixed_indexquals, fixed_qual);
 		*indxstrategy = lappend(*indxstrategy, strategy);
@@ -1222,9 +1217,7 @@ fix_indxqual_references(List *indexquals, IndexPath *index_path,
  *		the integer list of lossiness flags (1/0)
  */
 static void
-fix_indxqual_sublist(List *indexqual,
-					 Relids baserelids, int baserelid,
-					 IndexOptInfo *index,
+fix_indxqual_sublist(List *indexqual, IndexOptInfo *index,
 					 List **fixed_quals,
 					 List **strategy,
 					 List **subtype,
@@ -1265,7 +1258,7 @@ fix_indxqual_sublist(List *indexqual,
 		 * the clause.	The indexkey should be the side that refers to
 		 * (only) the base relation.
 		 */
-		if (!bms_equal(rinfo->left_relids, baserelids))
+		if (!bms_equal(rinfo->left_relids, index->rel->relids))
 			CommuteClause(newclause);
 
 		/*
@@ -1273,7 +1266,6 @@ fix_indxqual_sublist(List *indexqual,
 		 * indexkey operand as needed, and get the index opclass.
 		 */
 		linitial(newclause->args) = fix_indxqual_operand(linitial(newclause->args),
-														 baserelid,
 														 index,
 														 &opclass);
 
@@ -1295,8 +1287,7 @@ fix_indxqual_sublist(List *indexqual,
 }
 
 static Node *
-fix_indxqual_operand(Node *node, int baserelid, IndexOptInfo *index,
-					 Oid *opclass)
+fix_indxqual_operand(Node *node, IndexOptInfo *index, Oid *opclass)
 {
 	/*
 	 * We represent index keys by Var nodes having the varno of the base
@@ -1316,7 +1307,7 @@ fix_indxqual_operand(Node *node, int baserelid, IndexOptInfo *index,
 		node = (Node *) ((RelabelType *) node)->arg;
 
 	if (IsA(node, Var) &&
-		((Var *) node)->varno == baserelid)
+		((Var *) node)->varno == index->rel->relid)
 	{
 		/* Try to match against simple index columns */
 		int			varatt = ((Var *) node)->varattno;
@@ -1353,7 +1344,7 @@ fix_indxqual_operand(Node *node, int baserelid, IndexOptInfo *index,
 			if (equal(node, indexkey))
 			{
 				/* Found a match */
-				result = makeVar(baserelid, pos + 1,
+				result = makeVar(index->rel->relid, pos + 1,
 								 exprType(lfirst(indexpr_item)), -1,
 								 0);
 				/* return the correct opclass, too */

src/backend/optimizer/util/pathnode.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/optimizer/util/pathnode.c,v 1.113 2005/03/26 23:29:18 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/optimizer/util/pathnode.c,v 1.114 2005/03/27 06:29:42 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -417,8 +417,7 @@ create_seqscan_path(Query *root, RelOptInfo *rel)
  * create_index_path
  *	  Creates a path node for an index scan.
  *
- * 'rel' is the parent rel
- * 'index' is an index on 'rel'
+ * 'index' is a usable index.
  * 'restriction_clauses' is a list of lists of RestrictInfo nodes
  *			to be used as index qual conditions in the scan.
  * 'pathkeys' describes the ordering of the path.
@@ -430,7 +429,6 @@ create_seqscan_path(Query *root, RelOptInfo *rel)
  */
 IndexPath *
 create_index_path(Query *root,
-				  RelOptInfo *rel,
 				  IndexOptInfo *index,
 				  List *restriction_clauses,
 				  List *pathkeys,
@@ -440,11 +438,11 @@ create_index_path(Query *root,
 	List	   *indexquals;
 
 	pathnode->path.pathtype = T_IndexScan;
-	pathnode->path.parent = rel;
+	pathnode->path.parent = index->rel;
 	pathnode->path.pathkeys = pathkeys;
 
 	/* Convert clauses to indexquals the executor can handle */
-	indexquals = expand_indexqual_conditions(rel, index, restriction_clauses);
+	indexquals = expand_indexqual_conditions(index, restriction_clauses);
 
 	/* Flatten the clause-groups list to produce indexclauses list */
 	restriction_clauses = flatten_clausegroups_list(restriction_clauses);
@@ -466,9 +464,9 @@ create_index_path(Query *root,
 	 * The number of rows is the same as the parent rel's estimate, since
 	 * this isn't a join inner indexscan.
 	 */
-	pathnode->rows = rel->rows;
+	pathnode->rows = index->rel->rows;
 
-	cost_index(&pathnode->path, root, rel, index, indexquals, false);
+	cost_index(&pathnode->path, root, index, indexquals, false);
 
 	return pathnode;
 }

src/backend/optimizer/util/plancat.c

@@ -9,7 +9,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/optimizer/util/plancat.c,v 1.101 2005/03/24 19:14:49 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/optimizer/util/plancat.c,v 1.102 2005/03/27 06:29:42 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -124,6 +124,7 @@ get_relation_info(Oid relationObjectId, RelOptInfo *rel)
 			info = makeNode(IndexOptInfo);
 
 			info->indexoid = index->indexrelid;
+			info->rel = rel;
 			info->ncolumns = ncolumns = index->indnatts;
 
 			/*

src/include/nodes/relation.h

@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/nodes/relation.h,v 1.103 2005/02/21 06:43:04 neilc Exp $
+ * $PostgreSQL: pgsql/src/include/nodes/relation.h,v 1.104 2005/03/27 06:29:45 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -253,6 +253,7 @@ typedef struct IndexOptInfo
 	NodeTag		type;
 
 	Oid			indexoid;		/* OID of the index relation */
+	RelOptInfo *rel;			/* back-link to index's table */
 
 	/* statistics from pg_class */
 	BlockNumber	pages;			/* number of disk pages in index */

src/include/optimizer/cost.h

@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/optimizer/cost.h,v 1.62 2004/12/31 22:03:36 pgsql Exp $
+ * $PostgreSQL: pgsql/src/include/optimizer/cost.h,v 1.63 2005/03/27 06:29:49 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -50,10 +50,8 @@ extern bool enable_mergejoin;
 extern bool enable_hashjoin;
 
 extern double clamp_row_est(double nrows);
-extern void cost_seqscan(Path *path, Query *root,
-			 RelOptInfo *baserel);
-extern void cost_index(Path *path, Query *root,
-		   RelOptInfo *baserel, IndexOptInfo *index,
+extern void cost_seqscan(Path *path, Query *root, RelOptInfo *baserel);
+extern void cost_index(Path *path, Query *root, IndexOptInfo *index,
 		   List *indexQuals, bool is_injoin);
 extern void cost_tidscan(Path *path, Query *root,
 			 RelOptInfo *baserel, List *tideval);

src/include/optimizer/pathnode.h

@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/optimizer/pathnode.h,v 1.56 2004/12/31 22:03:36 pgsql Exp $
+ * $PostgreSQL: pgsql/src/include/optimizer/pathnode.h,v 1.57 2005/03/27 06:29:49 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -28,7 +28,7 @@ extern void set_cheapest(RelOptInfo *parent_rel);
 extern void add_path(RelOptInfo *parent_rel, Path *new_path);
 
 extern Path *create_seqscan_path(Query *root, RelOptInfo *rel);
-extern IndexPath *create_index_path(Query *root, RelOptInfo *rel,
+extern IndexPath *create_index_path(Query *root,
 				  IndexOptInfo *index,
 				  List *restriction_clauses,
 				  List *pathkeys,

src/include/optimizer/paths.h

@@ -8,7 +8,7 @@
  * Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/optimizer/paths.h,v 1.79 2005/03/26 23:29:20 tgl Exp $
+ * $PostgreSQL: pgsql/src/include/optimizer/paths.h,v 1.80 2005/03/27 06:29:49 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -38,11 +38,9 @@ extern void debug_print_rel(Query *root, RelOptInfo *rel);
 extern void create_index_paths(Query *root, RelOptInfo *rel);
 extern Path *best_inner_indexscan(Query *root, RelOptInfo *rel,
 					 Relids outer_relids, JoinType jointype);
-extern List *group_clauses_by_indexkey_for_or(RelOptInfo *rel,
-								 IndexOptInfo *index,
+extern List *group_clauses_by_indexkey_for_or(IndexOptInfo *index,
 								 Expr *orsubclause);
-extern List *expand_indexqual_conditions(RelOptInfo *rel,
-										 IndexOptInfo *index,
+extern List *expand_indexqual_conditions(IndexOptInfo *index,
 										 List *clausegroups);
 extern void check_partial_indexes(Query *root, RelOptInfo *rel);
 extern bool pred_test(List *predicate_list, List *restrictinfo_list);
@@ -108,8 +106,7 @@ extern Path *get_cheapest_path_for_pathkeys(List *paths, List *pathkeys,
 extern Path *get_cheapest_fractional_path_for_pathkeys(List *paths,
 										  List *pathkeys,
 										  double fraction);
-extern List *build_index_pathkeys(Query *root, RelOptInfo *rel,
-					 IndexOptInfo *index,
+extern List *build_index_pathkeys(Query *root, IndexOptInfo *index,
 					 ScanDirection scandir);
 extern List *build_subquery_pathkeys(Query *root, RelOptInfo *rel,
 						Query *subquery);