From 749c86bea70bed0d6b91fd656627b864e74369d3 Mon Sep 17 00:00:00 2001 From: "Andrei V. Lepikhov" Date: Wed, 23 Jul 2025 13:46:02 +0200 Subject: [PATCH v1] Force RowMark Sanity Checking The SJE feature eliminates incorrect RowMarks without introducing any potential errors. This is due to a straightforward reason: the planned RowMark is used to reference a rtable entry in later execution stages. An RTE entry for keeping and removing relations is identical and refers to the same relation OID. To reduce confusion and prevent future issues, this commit cleans up the code and fixes the incorrect behaviour. Additionally, it renames variables to make similar errors more apparent in the future. Furthermore, it includes sanity checks in setrefs.c on existing non-null RTE and RelOptInfo entries for each RowMark. --- src/backend/optimizer/plan/analyzejoins.c | 49 ++++++++++++----------- src/backend/optimizer/plan/setrefs.c | 4 ++ 2 files changed, 30 insertions(+), 23 deletions(-) diff --git a/src/backend/optimizer/plan/analyzejoins.c b/src/backend/optimizer/plan/analyzejoins.c index 4d55c2ea591..df63f1699dc 100644 --- a/src/backend/optimizer/plan/analyzejoins.c +++ b/src/backend/optimizer/plan/analyzejoins.c @@ -631,6 +631,7 @@ remove_leftjoinrel_from_query(PlannerInfo *root, int relid, * remove_join_clause_from_rels will touch it.) */ root->simple_rel_array[relid] = NULL; + root->simple_rte_array[relid] = NULL; /* And nuke the RelOptInfo, just in case there's another access path */ pfree(rel); @@ -1979,10 +1980,12 @@ remove_self_join_rel(PlannerInfo *root, PlanRowMark *kmark, PlanRowMark *rmark, * remove_join_clause_from_rels will touch it.) */ root->simple_rel_array[toRemove->relid] = NULL; + root->simple_rte_array[toRemove->relid] = NULL; /* And nuke the RelOptInfo, just in case there's another access path. */ pfree(toRemove); + /* * Now repeat construction of attr_needed bits coming from all other * sources. @@ -2142,21 +2145,21 @@ remove_self_joins_one_group(PlannerInfo *root, Relids relids) while ((r = bms_next_member(relids, r)) > 0) { - RelOptInfo *inner = root->simple_rel_array[r]; + RelOptInfo *rrel = root->simple_rel_array[r]; k = r; while ((k = bms_next_member(relids, k)) > 0) { Relids joinrelids = NULL; - RelOptInfo *outer = root->simple_rel_array[k]; + RelOptInfo *krel = root->simple_rel_array[k]; List *restrictlist; List *selfjoinquals; List *otherjoinquals; ListCell *lc; bool jinfo_check = true; - PlanRowMark *omark = NULL; - PlanRowMark *imark = NULL; + PlanRowMark *kmark = NULL; + PlanRowMark *rmark = NULL; List *uclauses = NIL; /* A sanity check: the relations have the same Oid. */ @@ -2194,21 +2197,21 @@ remove_self_joins_one_group(PlannerInfo *root, Relids relids) { PlanRowMark *rowMark = (PlanRowMark *) lfirst(lc); - if (rowMark->rti == k) + if (rowMark->rti == r) { - Assert(imark == NULL); - imark = rowMark; + Assert(rmark == NULL); + rmark = rowMark; } - else if (rowMark->rti == r) + else if (rowMark->rti == k) { - Assert(omark == NULL); - omark = rowMark; + Assert(kmark == NULL); + kmark = rowMark; } - if (omark && imark) + if (kmark && rmark) break; } - if (omark && imark && omark->markType != imark->markType) + if (kmark && rmark && kmark->markType != rmark->markType) continue; /* @@ -2229,8 +2232,8 @@ remove_self_joins_one_group(PlannerInfo *root, Relids relids) * build_joinrel_restrictlist() routine. */ restrictlist = generate_join_implied_equalities(root, joinrelids, - inner->relids, - outer, NULL); + rrel->relids, + krel, NULL); if (restrictlist == NIL) continue; @@ -2240,7 +2243,7 @@ remove_self_joins_one_group(PlannerInfo *root, Relids relids) * otherjoinquals. */ split_selfjoin_quals(root, restrictlist, &selfjoinquals, - &otherjoinquals, inner->relid, outer->relid); + &otherjoinquals, rrel->relid, krel->relid); Assert(list_length(restrictlist) == (list_length(selfjoinquals) + list_length(otherjoinquals))); @@ -2251,17 +2254,17 @@ remove_self_joins_one_group(PlannerInfo *root, Relids relids) * degenerate case works only if both sides have the same clause. * So doesn't matter which side to add. */ - selfjoinquals = list_concat(selfjoinquals, outer->baserestrictinfo); + selfjoinquals = list_concat(selfjoinquals, krel->baserestrictinfo); /* - * Determine if the inner table can duplicate outer rows. We must + * Determine if the rrel can duplicate outer rows. We must * bypass the unique rel cache here since we're possibly using a * subset of join quals. We can use 'force_cache' == true when all * join quals are self-join quals. Otherwise, we could end up * putting false negatives in the cache. */ - if (!innerrel_is_unique_ext(root, joinrelids, inner->relids, - outer, JOIN_INNER, selfjoinquals, + if (!innerrel_is_unique_ext(root, joinrelids, rrel->relids, + krel, JOIN_INNER, selfjoinquals, list_length(otherjoinquals) == 0, &uclauses)) continue; @@ -2277,14 +2280,14 @@ remove_self_joins_one_group(PlannerInfo *root, Relids relids) * expressions, or we won't match the same row on each side of the * join. */ - if (!match_unique_clauses(root, inner, uclauses, outer->relid)) + if (!match_unique_clauses(root, rrel, uclauses, krel->relid)) continue; /* - * We can remove either relation, so remove the inner one in order - * to simplify this loop. + * Remove rrel ReloptInfo from the planner structures and the + * corresponding row mark. */ - remove_self_join_rel(root, omark, imark, outer, inner, restrictlist); + remove_self_join_rel(root, kmark, rmark, krel, rrel, restrictlist); result = bms_add_member(result, r); diff --git a/src/backend/optimizer/plan/setrefs.c b/src/backend/optimizer/plan/setrefs.c index 846e44186c3..d706546f332 100644 --- a/src/backend/optimizer/plan/setrefs.c +++ b/src/backend/optimizer/plan/setrefs.c @@ -307,6 +307,10 @@ set_plan_references(PlannerInfo *root, Plan *plan) PlanRowMark *rc = lfirst_node(PlanRowMark, lc); PlanRowMark *newrc; + /* sanity check on existing row marks */ + Assert(root->simple_rel_array[rc->rti] != NULL && + root->simple_rte_array[rc->rti] != NULL); + /* flat copy is enough since all fields are scalars */ newrc = (PlanRowMark *) palloc(sizeof(PlanRowMark)); memcpy(newrc, rc, sizeof(PlanRowMark)); -- 2.50.1