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Further planner/optimizer cleanups. Move all set_tlist_references

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and fix_opids processing to a single recursive pass over the plan tree
executed at the very tail end of planning, rather than haphazardly here
and there at different places.  Now that tlist Vars do not get modified
until the very end, it's possible to get rid of the klugy var_equal and
match_varid partial-matching routines, and just use plain equal()
throughout the optimizer.  This is a step towards allowing merge and
hash joins to be done on expressions instead of only Vars ...
This commit is contained in:
Tom Lane
1999-08-22 20:15:04 +00:00
parent db436adf76
commit 78114cd4d4
24 changed files with 662 additions and 963 deletions
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95
src/backend/optimizer/path/pathkeys.c
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@ -7,7 +7,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/optimizer/path/pathkeys.c,v 1.15 1999/08/21 03:49:01 tgl Exp $
* $Header: /cvsroot/pgsql/src/backend/optimizer/path/pathkeys.c,v 1.16 1999/08/22 20:14:42 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -24,8 +24,6 @@
#include "utils/lsyscache.h"
static PathKeyItem *makePathKeyItem(Node *key, Oid sortop);
static bool pathkeyitem_equal(PathKeyItem *a, PathKeyItem *b);
static bool pathkeyitem_member(PathKeyItem *a, List *l);
static Var *find_indexkey_var(int indexkey, List *tlist);
static List *build_join_pathkey(List *pathkeys, List *join_rel_tlist,
List *joinclauses);
@ -118,45 +116,6 @@ makePathKeyItem(Node *key, Oid sortop)
* PATHKEY COMPARISONS
****************************************************************************/
/*
* Compare two pathkey items for equality.
*
* This is unlike straight equal() because when the two keys are both Vars,
* we want to apply the weaker var_equal() condition (doesn't check varnoold
* or varoattno). But if that fails, try equal() so that we recognize
* functional-index keys.
*/
static bool
pathkeyitem_equal (PathKeyItem *a, PathKeyItem *b)
{
Assert(a && IsA(a, PathKeyItem));
Assert(b && IsA(b, PathKeyItem));
if (a->sortop != b->sortop)
return false;
if (var_equal((Var *) a->key, (Var *) b->key))
return true;
return equal(a->key, b->key);
}
/*
* member() test using pathkeyitem_equal
*/
static bool
pathkeyitem_member (PathKeyItem *a, List *l)
{
List *i;
Assert(a && IsA(a, PathKeyItem));
foreach(i, l)
{
if (pathkeyitem_equal(a, (PathKeyItem *) lfirst(i)))
return true;
}
return false;
}
/*
* compare_pathkeys
* Compare two pathkeys to see if they are equivalent, and if not whether
@ -191,7 +150,7 @@ compare_pathkeys(List *keys1, List *keys2)
{
foreach(i, subkey1)
{
if (! pathkeyitem_member((PathKeyItem *) lfirst(i), subkey2))
if (! member(lfirst(i), subkey2))
{
key1_subsetof_key2 = false;
break;
@ -203,7 +162,7 @@ compare_pathkeys(List *keys1, List *keys2)
{
foreach(i, subkey2)
{
if (! pathkeyitem_member((PathKeyItem *) lfirst(i), subkey1))
if (! member(lfirst(i), subkey1))
{
key2_subsetof_key1 = false;
break;
@ -336,8 +295,8 @@ build_index_pathkeys(Query *root, RelOptInfo *rel, RelOptInfo *index)
int32 type_mod = get_atttypmod(reloid, varattno);
funcargs = lappend(funcargs,
makeVar(relid, varattno, vartypeid, type_mod,
0, relid, varattno));
makeVar(relid, varattno, vartypeid,
type_mod, 0));
indexkeys++;
}
@ -483,13 +442,13 @@ build_join_pathkey(List *pathkey,
foreach(i, pathkey)
{
PathKeyItem *key = (PathKeyItem *) lfirst(i);
Expr *tlist_key;
Node *tlist_key;
Assert(key && IsA(key, PathKeyItem));
tlist_key = matching_tlist_var((Var *) key->key, join_rel_tlist);
tlist_key = matching_tlist_expr(key->key, join_rel_tlist);
if (tlist_key)
new_pathkey = lcons(makePathKeyItem((Node *) tlist_key,
new_pathkey = lcons(makePathKeyItem(tlist_key,
key->sortop),
new_pathkey);
@ -498,17 +457,17 @@ build_join_pathkey(List *pathkey,
RestrictInfo *restrictinfo = (RestrictInfo *) lfirst(j);
Expr *joinclause = restrictinfo->clause;
/* We assume the clause is a binary opclause... */
Var *l = get_leftop(joinclause);
Var *r = get_rightop(joinclause);
Var *other_var = NULL;
Node *l = (Node *) get_leftop(joinclause);
Node *r = (Node *) get_rightop(joinclause);
Node *other_var = NULL;
Oid other_sortop = InvalidOid;
if (var_equal((Var *) key->key, l))
if (equal(key->key, l))
{
other_var = r;
other_sortop = restrictinfo->right_sortop;
}
else if (var_equal((Var *) key->key, r))
else if (equal(key->key, r))
{
other_var = l;
other_sortop = restrictinfo->left_sortop;
@ -516,9 +475,9 @@ build_join_pathkey(List *pathkey,
if (other_var && other_sortop)
{
tlist_key = matching_tlist_var(other_var, join_rel_tlist);
tlist_key = matching_tlist_expr(other_var, join_rel_tlist);
if (tlist_key)
new_pathkey = lcons(makePathKeyItem((Node *) tlist_key,
new_pathkey = lcons(makePathKeyItem(tlist_key,
other_sortop),
new_pathkey);
}
@ -638,20 +597,17 @@ find_mergeclauses_for_pathkeys(List *pathkeys, List *restrictinfos)
foreach(j, pathkey)
{
PathKeyItem *keyitem = lfirst(j);
Var *keyvar = (Var *) keyitem->key;
Node *key = keyitem->key;
List *k;
if (! IsA(keyvar, Var))
continue; /* for now, only Vars can be mergejoined */
foreach(k, restrictinfos)
{
RestrictInfo *restrictinfo = lfirst(k);
Assert(restrictinfo->mergejoinoperator != InvalidOid);
if ((var_equal(keyvar, get_leftop(restrictinfo->clause)) ||
var_equal(keyvar, get_rightop(restrictinfo->clause))) &&
if ((equal(key, get_leftop(restrictinfo->clause)) ||
equal(key, get_rightop(restrictinfo->clause))) &&
! member(restrictinfo, mergeclauses))
{
matched_restrictinfo = restrictinfo;
@ -705,23 +661,24 @@ make_pathkeys_for_mergeclauses(List *mergeclauses, List *tlist)
foreach(i, mergeclauses)
{
RestrictInfo *restrictinfo = (RestrictInfo *) lfirst(i);
Var *key;
Node *key;
Oid sortop;
Assert(restrictinfo->mergejoinoperator != InvalidOid);
/*
* Find the key and sortop needed for this mergeclause.
*
* We can use either side of the mergeclause, since we haven't yet
* committed to which side will be inner.
*/
Assert(restrictinfo->mergejoinoperator != InvalidOid);
key = (Var *) matching_tlist_var(get_leftop(restrictinfo->clause),
tlist);
key = matching_tlist_expr((Node *) get_leftop(restrictinfo->clause),
tlist);
sortop = restrictinfo->left_sortop;
if (! key)
{
key = (Var *) matching_tlist_var(get_rightop(restrictinfo->clause),
tlist);
key = matching_tlist_expr((Node *) get_rightop(restrictinfo->clause),
tlist);
sortop = restrictinfo->right_sortop;
}
if (! key)
@ -730,7 +687,7 @@ make_pathkeys_for_mergeclauses(List *mergeclauses, List *tlist)
* Add a pathkey sublist for this sort item
*/
pathkeys = lappend(pathkeys,
lcons(makePathKeyItem((Node *) key, sortop),
lcons(makePathKeyItem(key, sortop),
NIL));
}