diff options
Diffstat (limited to 'src/backend/optimizer/path/joinrels.c')
| -rw-r--r-- | src/backend/optimizer/path/joinrels.c | 16 |
1 files changed, 12 insertions, 4 deletions
diff --git a/src/backend/optimizer/path/joinrels.c b/src/backend/optimizer/path/joinrels.c index bed9db50430..17b5f31915a 100644 --- a/src/backend/optimizer/path/joinrels.c +++ b/src/backend/optimizer/path/joinrels.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/optimizer/path/joinrels.c,v 1.80 2006/10/04 00:29:54 momjian Exp $ + * $PostgreSQL: pgsql/src/backend/optimizer/path/joinrels.c,v 1.81 2006/10/24 17:50:22 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -87,9 +87,9 @@ make_rels_by_joins(PlannerInfo *root, int level, List **joinrels) /* * An exception occurs when there is a clauseless join inside a - * construct that restricts join order, i.e., an outer join RHS or + * construct that restricts join order, i.e., an outer join or * an IN (sub-SELECT) construct. Here, the rel may well have join - * clauses against stuff outside the OJ RHS or IN sub-SELECT, but + * clauses against stuff outside its OJ side or IN sub-SELECT, but * the clauseless join *must* be done before we can make use of * those join clauses. So do the clauseless join bit. * @@ -331,7 +331,7 @@ make_rels_by_clauseless_joins(PlannerInfo *root, /* * has_join_restriction * Detect whether the specified relation has join-order restrictions - * due to being inside an OJ RHS or an IN (sub-SELECT). + * due to being inside an outer join or an IN (sub-SELECT). */ static bool has_join_restriction(PlannerInfo *root, RelOptInfo *rel) @@ -342,8 +342,16 @@ has_join_restriction(PlannerInfo *root, RelOptInfo *rel) { OuterJoinInfo *ojinfo = (OuterJoinInfo *) lfirst(l); + /* ignore full joins --- other mechanisms preserve their ordering */ + if (ojinfo->is_full_join) + continue; + /* anything inside the RHS is definitely restricted */ if (bms_is_subset(rel->relids, ojinfo->min_righthand)) return true; + /* if it's a proper subset of the LHS, it's also restricted */ + if (bms_is_subset(rel->relids, ojinfo->min_lefthand) && + !bms_equal(rel->relids, ojinfo->min_lefthand)) + return true; } foreach(l, root->in_info_list) |