Update optimizer comments.

This commit is contained in:
Bruce Momjian 1999-02-04 19:20:12 +00:00
parent 19cc38b28d
commit ae12e25263
2 changed files with 18 additions and 13 deletions

View File

@ -7,7 +7,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/optimizer/path/Attic/prune.c,v 1.18 1999/02/04 01:46:58 momjian Exp $
* $Header: /cvsroot/pgsql/src/backend/optimizer/path/Attic/prune.c,v 1.19 1999/02/04 19:20:11 momjian Exp $
*
*-------------------------------------------------------------------------
*/
@ -64,16 +64,18 @@ prune_joinrel(RelOptInfo *rel, List *other_rels)
List *i = NIL;
List *result = NIL;
foreach(i, other_rels)
foreach(r1, other_rels)
{
RelOptInfo *other_rel = (RelOptInfo *) lfirst(i);
RelOptInfo *other_rel = (RelOptInfo *) lfirst(r1);
if (same(rel->relids, other_rel->relids))
{
/*
* This are on the same relations,
* so get the best of their pathlists.
*/
rel->pathlist = add_pathlist(rel,
rel->pathlist,
other_rel->pathlist);
}
else
result = nconc(result, lcons(other_rel, NIL));
}

View File

@ -7,7 +7,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/optimizer/util/pathnode.c,v 1.17 1999/02/04 01:46:59 momjian Exp $
* $Header: /cvsroot/pgsql/src/backend/optimizer/util/pathnode.c,v 1.18 1999/02/04 19:20:12 momjian Exp $
*
*-------------------------------------------------------------------------
*/
@ -101,21 +101,24 @@ set_cheapest(RelOptInfo *parent_rel, List *pathlist)
List *
add_pathlist(RelOptInfo *parent_rel, List *unique_paths, List *new_paths)
{
List *x;
Path *new_path;
Path *old_path;
bool noOther;
List *p1;
foreach(x, new_paths)
foreach(p1, new_paths)
{
new_path = (Path *) lfirst(x);
Path *new_path = (Path *) lfirst(p1);
Path *old_path;
bool noOther;
/* Is this new path already in unique_paths? */
if (member(new_path, unique_paths))
continue;
/* Find best matching path */
old_path = better_path(new_path, unique_paths, &noOther);
if (noOther)
{
/* Is a brand new path. */
/* This is a brand new path. */
new_path->parent = parent_rel;
unique_paths = lcons(new_path, unique_paths);
}