From dd979f66be20fc54aad06da743f788fbc505bbe1 Mon Sep 17 00:00:00 2001
From: Tom Lane <tgl@sss.pgh.pa.us>
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/backend/nodes/readfuncs.c | 39 +++------------------------------------
 1 file changed, 3 insertions(+), 36 deletions(-)

(limited to 'src/backend/nodes/readfuncs.c')

diff --git a/src/backend/nodes/readfuncs.c b/src/backend/nodes/readfuncs.c
index cf63506a05f..9dccbf50170 100644
--- a/src/backend/nodes/readfuncs.c
+++ b/src/backend/nodes/readfuncs.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/nodes/readfuncs.c,v 1.80 2000/01/26 05:56:32 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/nodes/readfuncs.c,v 1.81 2000/01/27 18:11:28 tgl Exp $
  *
  * NOTES
  *	  Most of the read functions for plan nodes are tested. (In fact, they
@@ -111,12 +111,8 @@ _readQuery()
 	token = lsptok(NULL, &length);		/* get unionall */
 	local_node->unionall = (token[0] == 't') ? true : false;
 
-	token = lsptok(NULL, &length);		/* skip :uniqueFlag */
-	token = lsptok(NULL, &length);		/* get uniqueFlag */
-	if (length == 0)
-		local_node->uniqueFlag = NULL;
-	else
-		local_node->uniqueFlag = debackslash(token, length);
+	token = lsptok(NULL, &length);		/* skip :distinctClause */
+	local_node->distinctClause = nodeRead(true);
 
 	token = lsptok(NULL, &length);		/* skip :sortClause */
 	local_node->sortClause = nodeRead(true);
@@ -624,33 +620,6 @@ _readAgg()
 	return local_node;
 }
 
-/* ----------------
- *		_readUnique
- *
- * For some reason, unique is a subclass of Noname.
- */
-static Unique *
-_readUnique()
-{
-	Unique	   *local_node;
-	char	   *token;
-	int			length;
-
-	local_node = makeNode(Unique);
-
-	_getPlan((Plan *) local_node);
-
-	token = lsptok(NULL, &length);		/* eat :nonameid */
-	token = lsptok(NULL, &length);		/* get :nonameid */
-	local_node->nonameid = atol(token);
-
-	token = lsptok(NULL, &length);		/* eat :keycount */
-	token = lsptok(NULL, &length);		/* get :keycount */
-	local_node->keycount = atoi(token);
-
-	return local_node;
-}
-
 /* ----------------
  *		_readHash
  *
@@ -1847,8 +1816,6 @@ parsePlanString(void)
 		return_value = _readSubLink();
 	else if (length == 3 && strncmp(token, "AGG", length) == 0)
 		return_value = _readAgg();
-	else if (length == 6 && strncmp(token, "UNIQUE", length) == 0)
-		return_value = _readUnique();
 	else if (length == 4 && strncmp(token, "HASH", length) == 0)
 		return_value = _readHash();
 	else if (length == 6 && strncmp(token, "RESDOM", length) == 0)
-- 
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