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Simplify the planner's join clause management by storing join clauses

of a relation in a flat 'joininfo' list.  The former arrangement grouped
the join clauses according to the set of unjoined relids used in each;
however, profiling on test cases involving lots of joins proves that
that data structure is a net loss.  It takes more time to group the
join clauses together than is saved by avoiding duplicate tests later.
It doesn't help any that there are usually not more than one or two
clauses per group ...
This commit is contained in:
Tom Lane
2005-06-09 04:19:00 +00:00
parent c51815afed
commit a31ad27fc5
19 changed files with 285 additions and 465 deletions

View File

@@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/optimizer/plan/initsplan.c,v 1.106 2005/06/05 22:32:55 tgl Exp $
* $PostgreSQL: pgsql/src/backend/optimizer/plan/initsplan.c,v 1.107 2005/06/09 04:18:59 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -169,7 +169,7 @@ add_vars_to_targetlist(PlannerInfo *root, List *vars, Relids where_needed)
/*
* distribute_quals_to_rels
* Recursively scan the query's join tree for WHERE and JOIN/ON qual
* clauses, and add these to the appropriate RestrictInfo and JoinInfo
* clauses, and add these to the appropriate restrictinfo and joininfo
* lists belonging to base RelOptInfos. Also, base RelOptInfos are marked
* with outerjoinset information, to aid in proper positioning of qual
* clauses that appear above outer joins.
@@ -346,7 +346,7 @@ mark_baserels_for_outer_join(PlannerInfo *root, Relids rels, Relids outerrels)
/*
* distribute_qual_to_rels
* Add clause information to either the 'RestrictInfo' or 'JoinInfo' field
* Add clause information to either the baserestrictinfo or joininfo list
* (depending on whether the clause is a join) of each base relation
* mentioned in the clause. A RestrictInfo node is created and added to
* the appropriate list for each rel. Also, if the clause uses a
@@ -508,7 +508,8 @@ distribute_qual_to_rels(PlannerInfo *root, Node *clause,
*/
restrictinfo = make_restrictinfo((Expr *) clause,
is_pushed_down,
valid_everywhere);
valid_everywhere,
relids);
/*
* Figure out where to attach it.
@@ -654,8 +655,8 @@ process_implied_equality(PlannerInfo *root,
/*
* If the exprs involve a single rel, we need to look at that rel's
* baserestrictinfo list. If multiple rels, any one will have a
* joininfo node for the rest, and we can scan any of 'em.
* baserestrictinfo list. If multiple rels, we can scan the joininfo
* list of any of 'em.
*/
if (membership == BMS_SINGLETON)
{
@@ -666,20 +667,14 @@ process_implied_equality(PlannerInfo *root,
{
Relids other_rels;
int first_rel;
JoinInfo *joininfo;
/* Copy relids, find and remove one member */
other_rels = bms_copy(relids);
first_rel = bms_first_member(other_rels);
bms_free(other_rels);
rel1 = find_base_rel(root, first_rel);
/* use remaining members to find join node */
joininfo = find_joininfo_node(rel1, other_rels);
restrictlist = joininfo ? joininfo->jinfo_restrictinfo : NIL;
bms_free(other_rels);
restrictlist = rel1->joininfo;
}
/*