diff --git a/src/backend/optimizer/path/equivclass.c b/src/backend/optimizer/path/equivclass.c index 441f12f6c50..54e0b5cbdd1 100644 --- a/src/backend/optimizer/path/equivclass.c +++ b/src/backend/optimizer/path/equivclass.c @@ -1453,8 +1453,7 @@ generate_base_implied_equalities_no_const(PlannerInfo *root, * For the moment we force all the Vars to be available at all join nodes * for this eclass. Perhaps this could be improved by doing some * pre-analysis of which members we prefer to join, but it's no worse than - * what happened in the pre-8.3 code. (Note: rebuild_eclass_attr_needed - * needs to match this code.) + * what happened in the pre-8.3 code. */ foreach(lc, ec->ec_members) { @@ -2561,51 +2560,6 @@ reconsider_full_join_clause(PlannerInfo *root, OuterJoinClauseInfo *ojcinfo) return false; /* failed to make any deduction */ } -/* - * rebuild_eclass_attr_needed - * Put back attr_needed bits for Vars/PHVs needed for join eclasses. - * - * This is used to rebuild attr_needed/ph_needed sets after removal of a - * useless outer join. It should match what - * generate_base_implied_equalities_no_const did, except that we call - * add_vars_to_attr_needed not add_vars_to_targetlist. - */ -void -rebuild_eclass_attr_needed(PlannerInfo *root) -{ - ListCell *lc; - - foreach(lc, root->eq_classes) - { - EquivalenceClass *ec = (EquivalenceClass *) lfirst(lc); - - /* - * We don't expect any EC child members to exist at this point. Ensure - * that's the case, otherwise, we might be getting asked to do - * something this function hasn't been coded for. - */ - Assert(ec->ec_childmembers == NULL); - - /* Need do anything only for a multi-member, no-const EC. */ - if (list_length(ec->ec_members) > 1 && !ec->ec_has_const) - { - ListCell *lc2; - - foreach(lc2, ec->ec_members) - { - EquivalenceMember *cur_em = (EquivalenceMember *) lfirst(lc2); - List *vars = pull_var_clause((Node *) cur_em->em_expr, - PVC_RECURSE_AGGREGATES | - PVC_RECURSE_WINDOWFUNCS | - PVC_INCLUDE_PLACEHOLDERS); - - add_vars_to_attr_needed(root, vars, ec->ec_relids); - list_free(vars); - } - } - } -} - /* * find_join_domain * Find the highest JoinDomain enclosed within the given relid set. diff --git a/src/backend/optimizer/plan/analyzejoins.c b/src/backend/optimizer/plan/analyzejoins.c index 4455a046d23..11ce7e33573 100644 --- a/src/backend/optimizer/plan/analyzejoins.c +++ b/src/backend/optimizer/plan/analyzejoins.c @@ -28,7 +28,6 @@ #include "optimizer/optimizer.h" #include "optimizer/pathnode.h" #include "optimizer/paths.h" -#include "optimizer/placeholder.h" #include "optimizer/planmain.h" #include "optimizer/restrictinfo.h" #include "rewrite/rewriteManip.h" @@ -344,6 +343,37 @@ remove_rel_from_query(PlannerInfo *root, RelOptInfo *rel, sjinfo->ojrelid); } + /* + * Remove references to the rel from other baserels' attr_needed arrays. + */ + for (rti = 1; rti < root->simple_rel_array_size; rti++) + { + RelOptInfo *otherrel = root->simple_rel_array[rti]; + int attroff; + + /* there may be empty slots corresponding to non-baserel RTEs */ + if (otherrel == NULL) + continue; + + Assert(otherrel->relid == rti); /* sanity check on array */ + + /* no point in processing target rel itself */ + if (otherrel == rel) + continue; + + for (attroff = otherrel->max_attr - otherrel->min_attr; + attroff >= 0; + attroff--) + { + otherrel->attr_needed[attroff] = + bms_del_member(otherrel->attr_needed[attroff], relid); + if (sjinfo != NULL) + otherrel->attr_needed[attroff] = + bms_del_member(otherrel->attr_needed[attroff], + sjinfo->ojrelid); + } + } + /* * Likewise remove references from SpecialJoinInfo data structures. * @@ -451,11 +481,13 @@ remove_rel_from_query(PlannerInfo *root, RelOptInfo *rel, phinfo->ph_eval_at = adjust_relid_set(phinfo->ph_eval_at, sjinfo->ojrelid, subst); Assert(!bms_is_empty(phinfo->ph_eval_at)); /* checked previously */ - /* Reduce ph_needed to contain only "relation 0"; see below */ - if (bms_is_member(0, phinfo->ph_needed)) - phinfo->ph_needed = bms_make_singleton(0); - else - phinfo->ph_needed = NULL; + + phinfo->ph_needed = adjust_relid_set(phinfo->ph_needed, + relid, subst); + if (sjinfo != NULL) + phinfo->ph_needed = adjust_relid_set(phinfo->ph_needed, + sjinfo->ojrelid, subst); + /* ph_needed might or might not become empty */ phinfo->ph_lateral = adjust_relid_set(phinfo->ph_lateral, relid, subst); @@ -490,46 +522,6 @@ remove_rel_from_query(PlannerInfo *root, RelOptInfo *rel, (sjinfo == NULL || bms_is_member(sjinfo->ojrelid, ec->ec_relids))) remove_rel_from_eclass(ec, sjinfo, relid, subst); } - - /* - * Finally, we must recompute per-Var attr_needed and per-PlaceHolderVar - * ph_needed relid sets. These have to be known accurately, else we may - * fail to remove other now-removable outer joins. And our removal of the - * join clause(s) for this outer join may mean that Vars that were - * formerly needed no longer are. So we have to do this honestly by - * repeating the construction of those relid sets. We can cheat to one - * small extent: we can avoid re-examining the targetlist and HAVING qual - * by preserving "relation 0" bits from the existing relid sets. This is - * safe because we'd never remove such references. - * - * So, start by removing all other bits from attr_needed sets and - * lateral_vars lists. (We already did this above for ph_needed.) - */ - for (rti = 1; rti < root->simple_rel_array_size; rti++) - { - RelOptInfo *otherrel = root->simple_rel_array[rti]; - int attroff; - - /* there may be empty slots corresponding to non-baserel RTEs */ - if (otherrel == NULL) - continue; - - Assert(otherrel->relid == rti); /* sanity check on array */ - - for (attroff = otherrel->max_attr - otherrel->min_attr; - attroff >= 0; - attroff--) - { - if (bms_is_member(0, otherrel->attr_needed[attroff])) - otherrel->attr_needed[attroff] = bms_make_singleton(0); - else - otherrel->attr_needed[attroff] = NULL; - } - - if (subst > 0) - ChangeVarNodesExtended((Node *) otherrel->lateral_vars, relid, - subst, 0, replace_relid_callback); - } } /* @@ -626,7 +618,7 @@ remove_leftjoinrel_from_query(PlannerInfo *root, int relid, */ /* - * Now remove the rel from the baserel array to prevent it from being + * Finally, remove the rel from the baserel array to prevent it from being * referenced again. (We can't do this earlier because * remove_join_clause_from_rels will touch it.) */ @@ -635,15 +627,6 @@ remove_leftjoinrel_from_query(PlannerInfo *root, int relid, /* And nuke the RelOptInfo, just in case there's another access path */ pfree(rel); - - /* - * Now repeat construction of attr_needed bits coming from all other - * sources. - */ - rebuild_placeholder_attr_needed(root); - rebuild_joinclause_attr_needed(root); - rebuild_eclass_attr_needed(root); - rebuild_lateral_attr_needed(root); } /* @@ -1984,16 +1967,6 @@ remove_self_join_rel(PlannerInfo *root, PlanRowMark *kmark, PlanRowMark *rmark, /* 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. - */ - rebuild_placeholder_attr_needed(root); - rebuild_joinclause_attr_needed(root); - rebuild_eclass_attr_needed(root); - rebuild_lateral_attr_needed(root); } /* diff --git a/src/backend/optimizer/plan/initsplan.c b/src/backend/optimizer/plan/initsplan.c index 01804b085b3..0ed6feb8cdd 100644 --- a/src/backend/optimizer/plan/initsplan.c +++ b/src/backend/optimizer/plan/initsplan.c @@ -275,8 +275,6 @@ build_base_rel_tlists(PlannerInfo *root, List *final_tlist) * have a single owning relation; we keep their attr_needed info in * root->placeholder_list instead. Find or create the associated * PlaceHolderInfo entry, and update its ph_needed. - * - * See also add_vars_to_attr_needed. */ void add_vars_to_targetlist(PlannerInfo *root, List *vars, @@ -330,62 +328,6 @@ add_vars_to_targetlist(PlannerInfo *root, List *vars, } } -/* - * add_vars_to_attr_needed - * This does a subset of what add_vars_to_targetlist does: it just - * updates attr_needed for Vars and ph_needed for PlaceHolderVars. - * We assume the Vars are already in their relations' targetlists. - * - * This is used to rebuild attr_needed/ph_needed sets after removal - * of a useless outer join. The removed join clause might have been - * the only upper-level use of some other relation's Var, in which - * case we can reduce that Var's attr_needed and thereby possibly - * open the door to further join removals. But we can't tell that - * without tedious reconstruction of the attr_needed data. - * - * Note that if a Var's attr_needed is successfully reduced to empty, - * it will still be in the relation's targetlist even though we do - * not really need the scan plan node to emit it. The extra plan - * inefficiency seems tiny enough to not be worth spending planner - * cycles to get rid of it. - */ -void -add_vars_to_attr_needed(PlannerInfo *root, List *vars, - Relids where_needed) -{ - ListCell *temp; - - Assert(!bms_is_empty(where_needed)); - - foreach(temp, vars) - { - Node *node = (Node *) lfirst(temp); - - if (IsA(node, Var)) - { - Var *var = (Var *) node; - RelOptInfo *rel = find_base_rel(root, var->varno); - int attno = var->varattno; - - if (bms_is_subset(where_needed, rel->relids)) - continue; - Assert(attno >= rel->min_attr && attno <= rel->max_attr); - attno -= rel->min_attr; - rel->attr_needed[attno] = bms_add_members(rel->attr_needed[attno], - where_needed); - } - else if (IsA(node, PlaceHolderVar)) - { - PlaceHolderVar *phv = (PlaceHolderVar *) node; - PlaceHolderInfo *phinfo = find_placeholder_info(root, phv); - - phinfo->ph_needed = bms_add_members(phinfo->ph_needed, - where_needed); - } - else - elog(ERROR, "unrecognized node type: %d", (int) nodeTag(node)); - } -} /***************************************************************************** * @@ -788,54 +730,10 @@ extract_lateral_references(PlannerInfo *root, RelOptInfo *brel, Index rtindex) */ add_vars_to_targetlist(root, newvars, where_needed); - /* - * Remember the lateral references for rebuild_lateral_attr_needed and - * create_lateral_join_info. - */ + /* Remember the lateral references for create_lateral_join_info */ brel->lateral_vars = newvars; } -/* - * rebuild_lateral_attr_needed - * Put back attr_needed bits for Vars/PHVs needed for lateral references. - * - * This is used to rebuild attr_needed/ph_needed sets after removal of a - * useless outer join. It should match what find_lateral_references did, - * except that we call add_vars_to_attr_needed not add_vars_to_targetlist. - */ -void -rebuild_lateral_attr_needed(PlannerInfo *root) -{ - Index rti; - - /* We need do nothing if the query contains no LATERAL RTEs */ - if (!root->hasLateralRTEs) - return; - - /* Examine the same baserels that find_lateral_references did */ - for (rti = 1; rti < root->simple_rel_array_size; rti++) - { - RelOptInfo *brel = root->simple_rel_array[rti]; - Relids where_needed; - - if (brel == NULL) - continue; - if (brel->reloptkind != RELOPT_BASEREL) - continue; - - /* - * We don't need to repeat all of extract_lateral_references, since it - * kindly saved the extracted Vars/PHVs in lateral_vars. - */ - if (brel->lateral_vars == NIL) - continue; - - where_needed = bms_make_singleton(rti); - - add_vars_to_attr_needed(root, brel->lateral_vars, where_needed); - } -} - /* * create_lateral_join_info * Fill in the per-base-relation direct_lateral_relids, lateral_relids @@ -2789,9 +2687,6 @@ distribute_qual_to_rels(PlannerInfo *root, Node *clause, * var propagation is ensured by making ojscope include input rels from * both sides of the join. * - * See also rebuild_joinclause_attr_needed, which has to partially repeat - * this work after removal of an outer join. - * * Note: if the clause gets absorbed into an EquivalenceClass then this * may be unnecessary, but for now we have to do it to cover the case * where the EC becomes ec_broken and we end up reinserting the original @@ -3401,11 +3296,6 @@ process_implied_equality(PlannerInfo *root, * some of the Vars could have missed having that done because they only * appeared in single-relation clauses originally. So do it here for * safety. - * - * See also rebuild_joinclause_attr_needed, which has to partially repeat - * this work after removal of an outer join. (Since we will put this - * clause into the joininfo lists, that function needn't do any extra work - * to find it.) */ if (bms_membership(relids) == BMS_MULTIPLE) { @@ -3547,72 +3437,6 @@ get_join_domain_min_rels(PlannerInfo *root, Relids domain_relids) } -/* - * rebuild_joinclause_attr_needed - * Put back attr_needed bits for Vars/PHVs needed for join clauses. - * - * This is used to rebuild attr_needed/ph_needed sets after removal of a - * useless outer join. It should match what distribute_qual_to_rels did, - * except that we call add_vars_to_attr_needed not add_vars_to_targetlist. - */ -void -rebuild_joinclause_attr_needed(PlannerInfo *root) -{ - /* - * We must examine all join clauses, but there's no value in processing - * any join clause more than once. So it's slightly annoying that we have - * to find them via the per-base-relation joininfo lists. Avoid duplicate - * processing by tracking the rinfo_serial numbers of join clauses we've - * already seen. (This doesn't work for is_clone clauses, so we must - * waste effort on them.) - */ - Bitmapset *seen_serials = NULL; - Index rti; - - /* Scan all baserels for join clauses */ - for (rti = 1; rti < root->simple_rel_array_size; rti++) - { - RelOptInfo *brel = root->simple_rel_array[rti]; - ListCell *lc; - - if (brel == NULL) - continue; - if (brel->reloptkind != RELOPT_BASEREL) - continue; - - foreach(lc, brel->joininfo) - { - RestrictInfo *rinfo = (RestrictInfo *) lfirst(lc); - Relids relids = rinfo->required_relids; - - if (!rinfo->is_clone) /* else serial number is not unique */ - { - if (bms_is_member(rinfo->rinfo_serial, seen_serials)) - continue; /* saw it already */ - seen_serials = bms_add_member(seen_serials, - rinfo->rinfo_serial); - } - - if (bms_membership(relids) == BMS_MULTIPLE) - { - List *vars = pull_var_clause((Node *) rinfo->clause, - PVC_RECURSE_AGGREGATES | - PVC_RECURSE_WINDOWFUNCS | - PVC_INCLUDE_PLACEHOLDERS); - Relids where_needed; - - if (rinfo->is_clone) - where_needed = bms_intersect(relids, root->all_baserels); - else - where_needed = relids; - add_vars_to_attr_needed(root, vars, where_needed); - list_free(vars); - } - } - } -} - - /* * match_foreign_keys_to_quals * Match foreign-key constraints to equivalence classes and join quals diff --git a/src/backend/optimizer/util/placeholder.c b/src/backend/optimizer/util/placeholder.c index e1cd00a72fb..d1ba8923b26 100644 --- a/src/backend/optimizer/util/placeholder.c +++ b/src/backend/optimizer/util/placeholder.c @@ -314,33 +314,6 @@ fix_placeholder_input_needed_levels(PlannerInfo *root) } } -/* - * rebuild_placeholder_attr_needed - * Put back attr_needed bits for Vars/PHVs needed in PlaceHolderVars. - * - * This is used to rebuild attr_needed/ph_needed sets after removal of a - * useless outer join. It should match what - * fix_placeholder_input_needed_levels did, except that we call - * add_vars_to_attr_needed not add_vars_to_targetlist. - */ -void -rebuild_placeholder_attr_needed(PlannerInfo *root) -{ - ListCell *lc; - - foreach(lc, root->placeholder_list) - { - PlaceHolderInfo *phinfo = (PlaceHolderInfo *) lfirst(lc); - List *vars = pull_var_clause((Node *) phinfo->ph_var->phexpr, - PVC_RECURSE_AGGREGATES | - PVC_RECURSE_WINDOWFUNCS | - PVC_INCLUDE_PLACEHOLDERS); - - add_vars_to_attr_needed(root, vars, phinfo->ph_eval_at); - list_free(vars); - } -} - /* * add_placeholders_to_base_rels * Add any required PlaceHolderVars to base rels' targetlists. diff --git a/src/include/optimizer/paths.h b/src/include/optimizer/paths.h index 8410531f2d6..e0924e622d4 100644 --- a/src/include/optimizer/paths.h +++ b/src/include/optimizer/paths.h @@ -129,7 +129,6 @@ extern bool process_equivalence(PlannerInfo *root, extern Expr *canonicalize_ec_expression(Expr *expr, Oid req_type, Oid req_collation); extern void reconsider_outer_join_clauses(PlannerInfo *root); -extern void rebuild_eclass_attr_needed(PlannerInfo *root); extern EquivalenceClass *get_eclass_for_sort_expr(PlannerInfo *root, Expr *expr, List *opfamilies, diff --git a/src/include/optimizer/placeholder.h b/src/include/optimizer/placeholder.h index db92d8861ba..a729e73d561 100644 --- a/src/include/optimizer/placeholder.h +++ b/src/include/optimizer/placeholder.h @@ -23,7 +23,6 @@ extern PlaceHolderInfo *find_placeholder_info(PlannerInfo *root, PlaceHolderVar *phv); extern void find_placeholders_in_jointree(PlannerInfo *root); extern void fix_placeholder_input_needed_levels(PlannerInfo *root); -extern void rebuild_placeholder_attr_needed(PlannerInfo *root); extern void add_placeholders_to_base_rels(PlannerInfo *root); extern void add_placeholders_to_joinrel(PlannerInfo *root, RelOptInfo *joinrel, RelOptInfo *outer_rel, RelOptInfo *inner_rel, diff --git a/src/include/optimizer/planmain.h b/src/include/optimizer/planmain.h index 9d3debcab28..e3bf9db6b6e 100644 --- a/src/include/optimizer/planmain.h +++ b/src/include/optimizer/planmain.h @@ -73,11 +73,8 @@ extern void add_other_rels_to_query(PlannerInfo *root); extern void build_base_rel_tlists(PlannerInfo *root, List *final_tlist); extern void add_vars_to_targetlist(PlannerInfo *root, List *vars, Relids where_needed); -extern void add_vars_to_attr_needed(PlannerInfo *root, List *vars, - Relids where_needed); extern void remove_useless_groupby_columns(PlannerInfo *root); extern void find_lateral_references(PlannerInfo *root); -extern void rebuild_lateral_attr_needed(PlannerInfo *root); extern void create_lateral_join_info(PlannerInfo *root); extern List *deconstruct_jointree(PlannerInfo *root); extern bool restriction_is_always_true(PlannerInfo *root, @@ -101,7 +98,6 @@ extern RestrictInfo *build_implied_join_equality(PlannerInfo *root, Expr *item2, Relids qualscope, Index security_level); -extern void rebuild_joinclause_attr_needed(PlannerInfo *root); extern void match_foreign_keys_to_quals(PlannerInfo *root); /* diff --git a/src/test/regress/expected/join.out b/src/test/regress/expected/join.out index 390aabfb34b..336def509bc 100644 --- a/src/test/regress/expected/join.out +++ b/src/test/regress/expected/join.out @@ -5853,13 +5853,11 @@ CREATE TEMP TABLE a (id int PRIMARY KEY, b_id int); CREATE TEMP TABLE b (id int PRIMARY KEY, c_id int); CREATE TEMP TABLE c (id int PRIMARY KEY); CREATE TEMP TABLE d (a int, b int); -CREATE TEMP TABLE e (id1 int, id2 int, PRIMARY KEY(id1, id2)); INSERT INTO a VALUES (0, 0), (1, NULL); INSERT INTO b VALUES (0, 0), (1, NULL); INSERT INTO c VALUES (0), (1); INSERT INTO d VALUES (1,3), (2,2), (3,1); -INSERT INTO e VALUES (0,0), (2,2), (3,1); --- all these cases should be optimizable into a simple seqscan +-- all three cases should be optimizable into a simple seqscan explain (costs off) SELECT a.* FROM a LEFT JOIN b ON a.b_id = b.id; QUERY PLAN --------------- @@ -5880,14 +5878,6 @@ explain (costs off) Seq Scan on a (1 row) -explain (costs off) - SELECT a.* FROM a LEFT JOIN b ON a.id = b.id - LEFT JOIN e ON e.id1 = a.b_id AND b.c_id = e.id2; - QUERY PLAN ---------------- - Seq Scan on a -(1 row) - -- check optimization of outer join within another special join explain (costs off) select id from a where id in ( diff --git a/src/test/regress/sql/join.sql b/src/test/regress/sql/join.sql index f6e7070db65..2850c20eb37 100644 --- a/src/test/regress/sql/join.sql +++ b/src/test/regress/sql/join.sql @@ -2086,22 +2086,17 @@ CREATE TEMP TABLE a (id int PRIMARY KEY, b_id int); CREATE TEMP TABLE b (id int PRIMARY KEY, c_id int); CREATE TEMP TABLE c (id int PRIMARY KEY); CREATE TEMP TABLE d (a int, b int); -CREATE TEMP TABLE e (id1 int, id2 int, PRIMARY KEY(id1, id2)); INSERT INTO a VALUES (0, 0), (1, NULL); INSERT INTO b VALUES (0, 0), (1, NULL); INSERT INTO c VALUES (0), (1); INSERT INTO d VALUES (1,3), (2,2), (3,1); -INSERT INTO e VALUES (0,0), (2,2), (3,1); --- all these cases should be optimizable into a simple seqscan +-- all three cases should be optimizable into a simple seqscan explain (costs off) SELECT a.* FROM a LEFT JOIN b ON a.b_id = b.id; explain (costs off) SELECT b.* FROM b LEFT JOIN c ON b.c_id = c.id; explain (costs off) SELECT a.* FROM a LEFT JOIN (b left join c on b.c_id = c.id) ON (a.b_id = b.id); -explain (costs off) - SELECT a.* FROM a LEFT JOIN b ON a.id = b.id - LEFT JOIN e ON e.id1 = a.b_id AND b.c_id = e.id2; -- check optimization of outer join within another special join explain (costs off)