Revise aggregate functions per earlier discussions in pghackers.

There's now only one transition value and transition function.
NULL handling in aggregates is a lot cleaner.  Also, use Numeric
accumulators instead of integer accumulators for sum/avg on integer
datatypes --- this avoids overflow at the cost of being a little slower.
Implement VARIANCE() and STDDEV() aggregates in the standard backend.

Also, enable new LIKE selectivity estimators by default.  Unrelated
change, but as long as I had to force initdb anyway...

4 files changed, 6 insertions, 15 deletions

diff --git a/src/backend/nodes/copyfuncs.c b/src/backend/nodes/copyfuncs.c
index bc305382dfe..4013a0f77b2 100644
--- a/src/backend/nodes/copyfuncs.c
+++ b/src/backend/nodes/copyfuncs.c
@@ -19,7 +19,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/nodes/copyfuncs.c,v 1.116 2000/07/12 02:37:04 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/nodes/copyfuncs.c,v 1.117 2000/07/17 03:04:58 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -843,7 +843,6 @@ _copyAggref(Aggref *from)
 	newnode->basetype = from->basetype;
 	newnode->aggtype = from->aggtype;
 	Node_Copy(from, newnode, target);
-	newnode->usenulls = from->usenulls;
 	newnode->aggstar = from->aggstar;
 	newnode->aggdistinct = from->aggdistinct;
 	newnode->aggno = from->aggno;		/* probably not needed */
diff --git a/src/backend/nodes/equalfuncs.c b/src/backend/nodes/equalfuncs.c
index b8814786180..b1772e6436c 100644
--- a/src/backend/nodes/equalfuncs.c
+++ b/src/backend/nodes/equalfuncs.c
@@ -24,7 +24,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/nodes/equalfuncs.c,v 1.68 2000/07/12 02:37:04 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/nodes/equalfuncs.c,v 1.69 2000/07/17 03:05:01 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -257,8 +257,6 @@ _equalAggref(Aggref *a, Aggref *b)
 		return false;
 	if (!equal(a->target, b->target))
 		return false;
-	if (a->usenulls != b->usenulls)
-		return false;
 	if (a->aggstar != b->aggstar)
 		return false;
 	if (a->aggdistinct != b->aggdistinct)
diff --git a/src/backend/nodes/outfuncs.c b/src/backend/nodes/outfuncs.c
index f6fed845069..c561ad51268 100644
--- a/src/backend/nodes/outfuncs.c
+++ b/src/backend/nodes/outfuncs.c
@@ -6,7 +6,7 @@
  * Portions Copyright (c) 1996-2000, PostgreSQL, Inc
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- *	$Header: /cvsroot/pgsql/src/backend/nodes/outfuncs.c,v 1.122 2000/07/15 00:01:37 tgl Exp $
+ *	$Header: /cvsroot/pgsql/src/backend/nodes/outfuncs.c,v 1.123 2000/07/17 03:05:01 tgl Exp $
  *
  * NOTES
  *	  Every (plan) node in POSTGRES has an associated "out" routine which
@@ -729,12 +729,10 @@ _outAggref(StringInfo str, Aggref *node)
 	appendStringInfo(str, " AGGREG :aggname ");
 	_outToken(str, node->aggname);
 	appendStringInfo(str, " :basetype %u :aggtype %u :target ",
-					 node->basetype,
-					 node->aggtype);
+					 node->basetype, node->aggtype);
 	_outNode(str, node->target);
 
-	appendStringInfo(str, " :usenulls %s :aggstar %s :aggdistinct %s ",
-					 node->usenulls ? "true" : "false",
+	appendStringInfo(str, " :aggstar %s :aggdistinct %s ",
 					 node->aggstar ? "true" : "false",
 					 node->aggdistinct ? "true" : "false");
 	/* aggno is not dumped */
diff --git a/src/backend/nodes/readfuncs.c b/src/backend/nodes/readfuncs.c
index 4754cbc327a..b9916ce6b06 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 1.92 2000/07/12 02:37:06 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/nodes/readfuncs.c,v 1.93 2000/07/17 03:05:01 tgl Exp $
  *
  * NOTES
  *	  Most of the read functions for plan nodes are tested. (In fact, they
@@ -1117,10 +1117,6 @@ _readAggref()
 	token = lsptok(NULL, &length);		/* eat :target */
 	local_node->target = nodeRead(true);		/* now read it */
 
-	token = lsptok(NULL, &length);		/* eat :usenulls */
-	token = lsptok(NULL, &length);		/* get usenulls */
-	local_node->usenulls = (token[0] == 't') ? true : false;
-
 	token = lsptok(NULL, &length);		/* eat :aggstar */
 	token = lsptok(NULL, &length);		/* get aggstar */
 	local_node->aggstar = (token[0] == 't') ? true : false;