Second try at fixing join alias variables. Instead of attaching miscellaneous

lists to join RTEs, attach a list of Vars and COALESCE expressions that will
replace the join's alias variables during planning.  This simplifies
flatten_join_alias_vars while still making it easy to fix up varno references
when transforming the query tree.  Add regression test cases for interactions
of subqueries with outer joins.

1 files changed, 22 insertions, 46 deletions

diff --git a/src/backend/optimizer/plan/createplan.c b/src/backend/optimizer/plan/createplan.c
index 79d90bf5a3c..c20abacca39 100644
--- a/src/backend/optimizer/plan/createplan.c
+++ b/src/backend/optimizer/plan/createplan.c
@@ -10,7 +10,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/optimizer/plan/createplan.c,v 1.112 2002/03/12 00:51:45 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/optimizer/plan/createplan.c,v 1.113 2002/04/28 19:54:28 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -80,18 +80,18 @@ static TidScan *make_tidscan(List *qptlist, List *qpqual, Index scanrelid,
 static NestLoop *make_nestloop(List *tlist,
 			  List *joinclauses, List *otherclauses,
 			  Plan *lefttree, Plan *righttree,
-			  JoinType jointype, Index joinrti);
+			  JoinType jointype);
 static HashJoin *make_hashjoin(List *tlist,
 			  List *joinclauses, List *otherclauses,
 			  List *hashclauses,
 			  Plan *lefttree, Plan *righttree,
-			  JoinType jointype, Index joinrti);
+			  JoinType jointype);
 static Hash *make_hash(List *tlist, Node *hashkey, Plan *lefttree);
 static MergeJoin *make_mergejoin(List *tlist,
 			   List *joinclauses, List *otherclauses,
 			   List *mergeclauses,
 			   Plan *lefttree, Plan *righttree,
-			   JoinType jointype, Index joinrti);
+			   JoinType jointype);
 
 /*
  * create_plan
@@ -591,7 +591,6 @@ create_nestloop_plan(Query *root,
 					 List *inner_tlist)
 {
 	NestLoop   *join_plan;
-	Index		joinrti = best_path->path.parent->joinrti;
 
 	if (IsA(inner_plan, IndexScan))
 	{
@@ -639,22 +638,19 @@ create_nestloop_plan(Query *root,
 													  root,
 													  outer_tlist,
 													  NIL,
-													  innerrel,
-													  joinrti);
+													  innerrel);
 			innerscan->indxqual = join_references(innerscan->indxqual,
 												  root,
 												  outer_tlist,
 												  NIL,
-												  innerrel,
-												  joinrti);
+												  innerrel);
 			/* fix the inner qpqual too, if it has join clauses */
 			if (NumRelids((Node *) inner_plan->qual) > 1)
 				inner_plan->qual = join_references(inner_plan->qual,
 												   root,
 												   outer_tlist,
 												   NIL,
-												   innerrel,
-												   joinrti);
+												   innerrel);
 		}
 	}
 	else if (IsA(inner_plan, TidScan))
@@ -665,8 +661,7 @@ create_nestloop_plan(Query *root,
 											 root,
 											 outer_tlist,
 											 inner_tlist,
-											 innerscan->scan.scanrelid,
-											 joinrti);
+											 innerscan->scan.scanrelid);
 	}
 	else if (IsA_Join(inner_plan))
 	{
@@ -688,22 +683,19 @@ create_nestloop_plan(Query *root,
 								  root,
 								  outer_tlist,
 								  inner_tlist,
-								  (Index) 0,
-								  joinrti);
+								  (Index) 0);
 	otherclauses = join_references(otherclauses,
 								   root,
 								   outer_tlist,
 								   inner_tlist,
-								   (Index) 0,
-								   joinrti);
+								   (Index) 0);
 
 	join_plan = make_nestloop(tlist,
 							  joinclauses,
 							  otherclauses,
 							  outer_plan,
 							  inner_plan,
-							  best_path->jointype,
-							  joinrti);
+							  best_path->jointype);
 
 	copy_path_costsize(&join_plan->join.plan, &best_path->path);
 
@@ -723,7 +715,6 @@ create_mergejoin_plan(Query *root,
 {
 	List	   *mergeclauses;
 	MergeJoin  *join_plan;
-	Index		joinrti = best_path->jpath.path.parent->joinrti;
 
 	mergeclauses = get_actual_clauses(best_path->path_mergeclauses);
 
@@ -736,8 +727,7 @@ create_mergejoin_plan(Query *root,
 								  root,
 								  outer_tlist,
 								  inner_tlist,
-								  (Index) 0,
-								  joinrti);
+								  (Index) 0);
 
 	/*
 	 * Fix the additional qpquals too.
@@ -746,8 +736,7 @@ create_mergejoin_plan(Query *root,
 								   root,
 								   outer_tlist,
 								   inner_tlist,
-								   (Index) 0,
-								   joinrti);
+								   (Index) 0);
 
 	/*
 	 * Now set the references in the mergeclauses and rearrange them so
@@ -757,8 +746,7 @@ create_mergejoin_plan(Query *root,
 												root,
 												outer_tlist,
 												inner_tlist,
-												(Index) 0,
-												joinrti));
+												(Index) 0));
 
 	/*
 	 * Create explicit sort nodes for the outer and inner join paths if
@@ -824,8 +812,7 @@ create_mergejoin_plan(Query *root,
 							   mergeclauses,
 							   outer_plan,
 							   inner_plan,
-							   best_path->jpath.jointype,
-							   joinrti);
+							   best_path->jpath.jointype);
 
 	copy_path_costsize(&join_plan->join.plan, &best_path->jpath.path);
 
@@ -847,7 +834,6 @@ create_hashjoin_plan(Query *root,
 	HashJoin   *join_plan;
 	Hash	   *hash_plan;
 	Node	   *innerhashkey;
-	Index		joinrti = best_path->jpath.path.parent->joinrti;
 
 	/*
 	 * NOTE: there will always be exactly one hashclause in the list
@@ -866,8 +852,7 @@ create_hashjoin_plan(Query *root,
 								  root,
 								  outer_tlist,
 								  inner_tlist,
-								  (Index) 0,
-								  joinrti);
+								  (Index) 0);
 
 	/*
 	 * Fix the additional qpquals too.
@@ -876,8 +861,7 @@ create_hashjoin_plan(Query *root,
 								   root,
 								   outer_tlist,
 								   inner_tlist,
-								   (Index) 0,
-								   joinrti);
+								   (Index) 0);
 
 	/*
 	 * Now set the references in the hashclauses and rearrange them so
@@ -887,8 +871,7 @@ create_hashjoin_plan(Query *root,
 											   root,
 											   outer_tlist,
 											   inner_tlist,
-											   (Index) 0,
-											   joinrti));
+											   (Index) 0));
 
 	/* Now the righthand op of the sole hashclause is the inner hash key. */
 	innerhashkey = (Node *) get_rightop(lfirst(hashclauses));
@@ -903,8 +886,7 @@ create_hashjoin_plan(Query *root,
 							  hashclauses,
 							  outer_plan,
 							  (Plan *) hash_plan,
-							  best_path->jpath.jointype,
-							  joinrti);
+							  best_path->jpath.jointype);
 
 	copy_path_costsize(&join_plan->join.plan, &best_path->jpath.path);
 
@@ -1363,8 +1345,7 @@ make_nestloop(List *tlist,
 			  List *otherclauses,
 			  Plan *lefttree,
 			  Plan *righttree,
-			  JoinType jointype,
-			  Index joinrti)
+			  JoinType jointype)
 {
 	NestLoop   *node = makeNode(NestLoop);
 	Plan	   *plan = &node->join.plan;
@@ -1377,7 +1358,6 @@ make_nestloop(List *tlist,
 	plan->righttree = righttree;
 	node->join.jointype = jointype;
 	node->join.joinqual = joinclauses;
-	node->join.joinrti = joinrti;
 
 	return node;
 }
@@ -1389,8 +1369,7 @@ make_hashjoin(List *tlist,
 			  List *hashclauses,
 			  Plan *lefttree,
 			  Plan *righttree,
-			  JoinType jointype,
-			  Index joinrti)
+			  JoinType jointype)
 {
 	HashJoin   *node = makeNode(HashJoin);
 	Plan	   *plan = &node->join.plan;
@@ -1404,7 +1383,6 @@ make_hashjoin(List *tlist,
 	node->hashclauses = hashclauses;
 	node->join.jointype = jointype;
 	node->join.joinqual = joinclauses;
-	node->join.joinrti = joinrti;
 
 	return node;
 }
@@ -1439,8 +1417,7 @@ make_mergejoin(List *tlist,
 			   List *mergeclauses,
 			   Plan *lefttree,
 			   Plan *righttree,
-			   JoinType jointype,
-			   Index joinrti)
+			   JoinType jointype)
 {
 	MergeJoin  *node = makeNode(MergeJoin);
 	Plan	   *plan = &node->join.plan;
@@ -1454,7 +1431,6 @@ make_mergejoin(List *tlist,
 	node->mergeclauses = mergeclauses;
 	node->join.jointype = jointype;
 	node->join.joinqual = joinclauses;
-	node->join.joinrti = joinrti;
 
 	return node;
 }