diff options
Diffstat (limited to 'src/backend')
| -rw-r--r-- | src/backend/optimizer/plan/analyzejoins.c | 68 |
1 files changed, 68 insertions, 0 deletions
diff --git a/src/backend/optimizer/plan/analyzejoins.c b/src/backend/optimizer/plan/analyzejoins.c index 6476e55e568..9161c8a2964 100644 --- a/src/backend/optimizer/plan/analyzejoins.c +++ b/src/backend/optimizer/plan/analyzejoins.c @@ -39,6 +39,8 @@ static void remove_rel_from_query(PlannerInfo *root, int relid, SpecialJoinInfo *sjinfo); static void remove_rel_from_restrictinfo(RestrictInfo *rinfo, int relid, int ojrelid); +static void remove_rel_from_eclass(EquivalenceClass *ec, + int relid, int ojrelid); static List *remove_rel_from_joinlist(List *joinlist, int relid, int *nremoved); static bool rel_supports_distinctness(PlannerInfo *root, RelOptInfo *rel); static bool rel_is_distinct_for(PlannerInfo *root, RelOptInfo *rel, @@ -512,6 +514,18 @@ remove_rel_from_query(PlannerInfo *root, int relid, SpecialJoinInfo *sjinfo) } /* + * Likewise remove references from EquivalenceClasses. + */ + foreach(l, root->eq_classes) + { + EquivalenceClass *ec = (EquivalenceClass *) lfirst(l); + + if (bms_is_member(relid, ec->ec_relids) || + bms_is_member(ojrelid, ec->ec_relids)) + remove_rel_from_eclass(ec, relid, ojrelid); + } + + /* * There may be references to the rel in root->fkey_list, but if so, * match_foreign_keys_to_quals() will get rid of them. */ @@ -584,6 +598,60 @@ remove_rel_from_restrictinfo(RestrictInfo *rinfo, int relid, int ojrelid) } /* + * Remove any references to relid or ojrelid from the EquivalenceClass. + * + * Like remove_rel_from_restrictinfo, we don't worry about cleaning out + * any nullingrel bits in contained Vars and PHVs. (This might have to be + * improved sometime.) We do need to fix the EC and EM relid sets to ensure + * that implied join equalities will be generated at the appropriate join + * level(s). + */ +static void +remove_rel_from_eclass(EquivalenceClass *ec, int relid, int ojrelid) +{ + ListCell *lc; + + /* Fix up the EC's overall relids */ + ec->ec_relids = bms_del_member(ec->ec_relids, relid); + ec->ec_relids = bms_del_member(ec->ec_relids, ojrelid); + + /* + * Fix up the member expressions. Any non-const member that ends with + * empty em_relids must be a Var or PHV of the removed relation. We don't + * need it anymore, so we can drop it. + */ + foreach(lc, ec->ec_members) + { + EquivalenceMember *cur_em = (EquivalenceMember *) lfirst(lc); + + if (bms_is_member(relid, cur_em->em_relids) || + bms_is_member(ojrelid, cur_em->em_relids)) + { + Assert(!cur_em->em_is_const); + cur_em->em_relids = bms_del_member(cur_em->em_relids, relid); + cur_em->em_relids = bms_del_member(cur_em->em_relids, ojrelid); + if (bms_is_empty(cur_em->em_relids)) + ec->ec_members = foreach_delete_current(ec->ec_members, lc); + } + } + + /* Fix up the source clauses, in case we can re-use them later */ + foreach(lc, ec->ec_sources) + { + RestrictInfo *rinfo = (RestrictInfo *) lfirst(lc); + + remove_rel_from_restrictinfo(rinfo, relid, ojrelid); + } + + /* + * Rather than expend code on fixing up any already-derived clauses, just + * drop them. (At this point, any such clauses would be base restriction + * clauses, which we'd not need anymore anyway.) + */ + ec->ec_derives = NIL; +} + +/* * Remove any occurrences of the target relid from a joinlist structure. * * It's easiest to build a whole new list structure, so we handle it that |