From dd979f66be20fc54aad06da743f788fbc505bbe1 Mon Sep 17 00:00:00 2001
From: Tom Lane
Date: Thu, 27 Jan 2000 18:11:50 +0000
Subject: Redesign DISTINCT ON as discussed in pgsql-sql 1/25/00: syntax is now
 SELECT DISTINCT ON (expr [, expr ...]) targetlist ... and there is a check to
 make sure that the user didn't specify an ORDER BY that's incompatible with
 the DISTINCT operation. Reimplement nodeUnique and nodeGroup to use the
 proper datatype-specific equality function for each column being compared ---
 they used to do bitwise comparisons or convert the data to text strings and
 strcmp(). (To add insult to injury, they'd look up the conversion functions
 once for each tuple...)  Parse/plan representation of DISTINCT is now a list
 of SortClause nodes. initdb forced by querytree change...

---
 src/include/optimizer/planmain.h | 4 ++--
 src/include/optimizer/tlist.h    | 5 ++++-
 2 files changed, 6 insertions(+), 3 deletions(-)

(limited to 'src/include/optimizer')

diff --git a/src/include/optimizer/planmain.h b/src/include/optimizer/planmain.h
index 826c5dbe3ce..340f54485cb 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 1.36 2000/01/26 05:58:20 momjian Exp $
+ * $Id: planmain.h,v 1.37 2000/01/27 18:11:45 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -33,7 +33,7 @@ extern Agg *make_agg(List *tlist, Plan *lefttree);
 extern Group *make_group(List *tlist, bool tuplePerGroup, int ngrp,
 		   AttrNumber *grpColIdx, Plan *lefttree);
 extern Noname *make_noname(List *tlist, List *pathkeys, Plan *subplan);
-extern Unique *make_unique(List *tlist, Plan *lefttree, char *uniqueAttr);
+extern Unique *make_unique(List *tlist, Plan *lefttree, List *distinctList);
 extern Result *make_result(List *tlist, Node *resconstantqual, Plan *subplan);
 
 /*
diff --git a/src/include/optimizer/tlist.h b/src/include/optimizer/tlist.h
index 986c47ee796..dba93c0d173 100644
--- a/src/include/optimizer/tlist.h
+++ b/src/include/optimizer/tlist.h
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2000, PostgreSQL, Inc
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: tlist.h,v 1.23 2000/01/26 05:58:21 momjian Exp $
+ * $Id: tlist.h,v 1.24 2000/01/27 18:11:45 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -28,6 +28,9 @@ extern List *flatten_tlist(List *tlist);
 extern List *add_to_flat_tlist(List *tlist, List *vars);
 
 extern Var *get_expr(TargetEntry *tle);
+
+extern TargetEntry *get_sortgroupclause_tle(SortClause *sortClause,
+											List *targetList);
 extern Node *get_sortgroupclause_expr(SortClause *sortClause,
 									  List *targetList);
 
-- 
cgit v1.2.3