Use a cleaner substitute for the inability to apply length() to the tail

of a list.  Per private discussion with Neil.

diff --git a/src/backend/optimizer/prep/prepjointree.c b/src/backend/optimizer/prep/prepjointree.c
index f916d54..37c6e96 100644 (file)
--- a/src/backend/optimizer/prep/prepjointree.c
+++ b/src/backend/optimizer/prep/prepjointree.c
@@ -16,7 +16,7 @@
  *
  *
  * IDENTIFICATION
- *       $PostgreSQL: pgsql/src/backend/optimizer/prep/prepjointree.c,v 1.18 2004/05/26 04:41:26 neilc Exp $
+ *       $PostgreSQL: pgsql/src/backend/optimizer/prep/prepjointree.c,v 1.19 2004/05/26 18:35:41 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -897,12 +897,15 @@ simplify_jointree(Query *parse, Node *jtnode)
        {
                FromExpr   *f = (FromExpr *) jtnode;
                List       *newlist = NIL;
+               int                     children_remaining;
                ListCell   *l;
 
+               children_remaining = list_length(f->fromlist);
                foreach(l, f->fromlist)
                {
                        Node       *child = (Node *) lfirst(l);
 
+                       children_remaining--;
                        /* Recursively simplify this child... */
                        child = simplify_jointree(parse, child);
                        /* Now, is it a FromExpr? */
@@ -917,16 +920,7 @@ simplify_jointree(Query *parse, Node *jtnode)
                                 */
                                FromExpr   *subf = (FromExpr *) child;
                                int                     childlen = length(subf->fromlist);
-                               int                     myothers;
-                               ListCell   *l2;
-
-                               /*
-                                * XXX: This is a quick hack, not sure of the proper
-                                * fix.
-                                */
-                               myothers = length(newlist);
-                               for_each_cell(l2, lnext(l))
-                                       myothers++;
+                               int                     myothers = length(newlist) + children_remaining;
 
                                if (childlen <= 1 ||
                                        (childlen + myothers) <= from_collapse_limit)