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Optimizer fix for samekeys() and cost fixes for longer optimizer keys.

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This commit is contained in:
Bruce Momjian
1999-02-11 04:08:44 +00:00
parent 403b3eff79
commit dbd80c97f4
3 changed files with 64 additions and 37 deletions
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62
src/backend/optimizer/util/pathnode.c
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@ -7,7 +7,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/optimizer/util/pathnode.c,v 1.23 1999/02/10 21:02:43 momjian Exp $
* $Header: /cvsroot/pgsql/src/backend/optimizer/util/pathnode.c,v 1.24 1999/02/11 04:08:43 momjian Exp $
*
*-------------------------------------------------------------------------
*/
@ -29,7 +29,7 @@
#include "parser/parsetree.h" /* for getrelid() */
static Path *better_path(Path *new_path, List *unique_paths, bool *noOther);
static Path *better_path(Path *new_path, List *unique_paths, bool *isNew);
/*****************************************************************************
@ -107,16 +107,16 @@ add_pathlist(RelOptInfo *parent_rel, List *unique_paths, List *new_paths)
{
Path *new_path = (Path *) lfirst(p1);
Path *old_path;
bool noOther;
bool is_new;
/* 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);
old_path = better_path(new_path, unique_paths, &is_new);
if (noOther)
if (is_new)
{
/* This is a brand new path. */
new_path->parent = parent_rel;
@ -153,19 +153,19 @@ add_pathlist(RelOptInfo *parent_rel, List *unique_paths, List *new_paths)
*
*/
static Path *
better_path(Path *new_path, List *unique_paths, bool *noOther)
better_path(Path *new_path, List *unique_paths, bool *is_new)
{
Path *old_path = (Path *) NULL;
Path *path = (Path *) NULL;
List *temp = NIL;
Path *retval = NULL;
int longer_key;
foreach(temp, unique_paths)
{
path = (Path *) lfirst(temp);
#ifdef OPTDUP_DEBUG
if (!samekeys(path->pathkeys, new_path->pathkeys))
if (!pathkeys_match(new_path->pathkeys, path->pathkeys, &longer_key) ||
longer_key != 0)
{
printf("oldpath\n");
pprint(path->pathkeys);
@ -176,8 +176,7 @@ better_path(Path *new_path, List *unique_paths, bool *noOther)
length(lfirst(path->pathkeys)) < length(lfirst(new_path->pathkeys)))
sleep(0); /* set breakpoint here */
}
if (!equal_path_ordering(path->path_order,
new_path->path_order))
if (!equal_path_ordering(new_path->path_order, path->path_order))
{
printf("oldord\n");
pprint(path->path_order);
@ -185,26 +184,35 @@ better_path(Path *new_path, List *unique_paths, bool *noOther)
pprint(new_path->path_order);
}
#endif
if (samekeys(path->pathkeys, new_path->pathkeys) &&
equal_path_ordering(path->path_order,
new_path->path_order))
if (pathkeys_match(new_path->pathkeys, path->pathkeys, &longer_key))
{
old_path = path;
break;
if (equal_path_ordering(new_path->path_order, path->path_order))
{
/*
* Replace pathkeys that match exactly, (1,2), (1,2).
* Replace pathkeys (1,2) with (1,2,3) if the latter is not
* more expensive and replace unordered path with ordered
* path if it is not more expensive.
*/
if ((longer_key == 0 && new_path->path_cost < path->path_cost) ||
(longer_key == 1 && new_path->path_cost <= path->path_cost) ||
(longer_key == 2 && new_path->path_cost >= path->path_cost))
{
*is_new = false;
return new_path;
}
else
{
*is_new = false;
return NULL;
}
}
}
}
if (old_path == NULL)
*noOther = true;
else
{
*noOther = false;
if (path_is_cheaper(new_path, old_path))
retval = old_path;
}
return retval;
*is_new = true;
return NULL;
}