Reimplementation of UNION/INTERSECT/EXCEPT. INTERSECT/EXCEPT now meet the

SQL92 semantics, including support for ALL option.  All three can be used
in subqueries and views.  DISTINCT and ORDER BY work now in views, too.
This rewrite fixes many problems with cross-datatype UNIONs and INSERT/SELECT
where the SELECT yields different datatypes than the INSERT needs.  I did
that by making UNION subqueries and SELECT in INSERT be treated like
subselects-in-FROM, thereby allowing an extra level of targetlist where the
datatype conversions can be inserted safely.
INITDB NEEDED!

4 files changed, 15 insertions, 6 deletions

diff --git a/src/include/optimizer/clauses.h b/src/include/optimizer/clauses.h
index 881940f9a1..612750dfaf 100644
--- a/src/include/optimizer/clauses.h
+++ b/src/include/optimizer/clauses.h
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2000, PostgreSQL, Inc
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: clauses.h,v 1.40 2000/09/29 18:21:40 tgl Exp $
+ * $Id: clauses.h,v 1.41 2000/10/05 19:11:37 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -75,7 +75,9 @@ extern bool expression_tree_walker(Node *node, bool (*walker) (),
 extern Node *expression_tree_mutator(Node *node, Node *(*mutator) (),
 									 void *context);
 extern bool query_tree_walker(Query *query, bool (*walker) (),
-							  void *context);
+							  void *context, bool visitQueryRTEs);
+extern void query_tree_mutator(Query *query, Node *(*mutator) (),
+							   void *context, bool visitQueryRTEs);
 
 #define is_subplan(clause)	((clause) != NULL && \
 							 IsA(clause, Expr) && \
diff --git a/src/include/optimizer/planmain.h b/src/include/optimizer/planmain.h
index e46d0bdbd8..015590a5ee 100644
--- a/src/include/optimizer/planmain.h
+++ b/src/include/optimizer/planmain.h
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2000, PostgreSQL, Inc
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: planmain.h,v 1.45 2000/09/29 18:21:40 tgl Exp $
+ * $Id: planmain.h,v 1.46 2000/10/05 19:11:37 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -26,6 +26,8 @@ extern Plan *query_planner(Query *root, List *tlist, double tuple_fraction);
  * prototypes for plan/createplan.c
  */
 extern Plan *create_plan(Query *root, Path *best_path);
+extern SubqueryScan *make_subqueryscan(List *qptlist, List *qpqual,
+									   Index scanrelid, Plan *subplan);
 extern Sort *make_sort(List *tlist, Plan *lefttree, int keycount);
 extern Sort *make_sort_from_pathkeys(List *tlist, Plan *lefttree,
 									 List *pathkeys);
@@ -34,7 +36,10 @@ extern Group *make_group(List *tlist, bool tuplePerGroup, int ngrp,
 		   AttrNumber *grpColIdx, Plan *lefttree);
 extern Material *make_material(List *tlist, Plan *lefttree);
 extern Unique *make_unique(List *tlist, Plan *lefttree, List *distinctList);
+extern SetOp *make_setop(SetOpCmd cmd, List *tlist, Plan *lefttree,
+						 List *distinctList, AttrNumber flagColIdx);
 extern Result *make_result(List *tlist, Node *resconstantqual, Plan *subplan);
+extern void copy_plan_costsize(Plan *dest, Plan *src);
 
 /*
  * prototypes for plan/initsplan.c
diff --git a/src/include/optimizer/planner.h b/src/include/optimizer/planner.h
index da099940e6..3fc0f435dc 100644
--- a/src/include/optimizer/planner.h
+++ b/src/include/optimizer/planner.h
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2000, PostgreSQL, Inc
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: planner.h,v 1.16 2000/08/21 20:55:28 tgl Exp $
+ * $Id: planner.h,v 1.17 2000/10/05 19:11:37 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -22,4 +22,6 @@ extern Plan *planner(Query *parse);
 extern Plan *subquery_planner(Query *parse, double tuple_fraction);
 extern Plan *union_planner(Query *parse, double tuple_fraction);
 
+extern Plan *make_sortplan(List *tlist, Plan *plannode, List *sortcls);
+
 #endif	 /* PLANNER_H */
diff --git a/src/include/optimizer/prep.h b/src/include/optimizer/prep.h
index 4ffddcf566..dcdf6fb62f 100644
--- a/src/include/optimizer/prep.h
+++ b/src/include/optimizer/prep.h
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2000, PostgreSQL, Inc
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: prep.h,v 1.23 2000/06/20 04:22:13 tgl Exp $
+ * $Id: prep.h,v 1.24 2000/10/05 19:11:37 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -32,11 +32,11 @@ extern List *preprocess_targetlist(List *tlist, int command_type,
 /*
  * prototypes for prepunion.c
  */
+extern Plan *plan_set_operations(Query *parse);
 extern List *find_all_inheritors(Oid parentrel);
 extern bool find_inheritable_rt_entry(List *rangetable,
 									  Index *rt_index, List **inheritors);
 extern Plan *plan_inherit_queries(Query *root, List *tlist,
 								  Index rt_index, List *inheritors);
-extern Plan *plan_union_queries(Query *parse);
 
 #endif	 /* PREP_H */