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[PATCH 2/3] Support clauses of the form Var op Var 6+ messages / 2 participants [nested] [flat]
* [PATCH 2/3] Support clauses of the form Var op Var @ 2019-11-11 00:34 Tomas Vondra <tv@fuzzy.cz> 0 siblings, 0 replies; 6+ messages in thread From: Tomas Vondra @ 2019-11-11 00:34 UTC (permalink / raw) --- src/backend/statistics/extended_stats.c | 63 ++++++++++++---- src/backend/statistics/mcv.c | 75 ++++++++++++++++++- .../statistics/extended_stats_internal.h | 2 +- src/test/regress/expected/stats_ext.out | 72 ++++++++++++++++++ src/test/regress/sql/stats_ext.sql | 22 ++++++ 5 files changed, 217 insertions(+), 17 deletions(-) diff --git a/src/backend/statistics/extended_stats.c b/src/backend/statistics/extended_stats.c index 24ece6f99c..1872cd4529 100644 --- a/src/backend/statistics/extended_stats.c +++ b/src/backend/statistics/extended_stats.c @@ -986,14 +986,18 @@ statext_is_compatible_clause_internal(PlannerInfo *root, Node *clause, { RangeTblEntry *rte = root->simple_rte_array[relid]; OpExpr *expr = (OpExpr *) clause; - Var *var; + Var *var, + *var2; /* Only expressions with two arguments are considered compatible. */ if (list_length(expr->args) != 2) return false; - /* Check if the expression the right shape (one Var, one Const) */ - if (!examine_opclause_expression(expr, &var, NULL, NULL)) + /* + * Check if the expression the right shape (one Var and one Const, + * or two Vars). + */ + if (!examine_opclause_expression(expr, &var, &var2, NULL, NULL)) return false; /* @@ -1033,7 +1037,20 @@ statext_is_compatible_clause_internal(PlannerInfo *root, Node *clause, !get_func_leakproof(get_opcode(expr->opno))) return false; - return statext_is_compatible_clause_internal(root, (Node *) var, + /* + * Check compatibility of the first Var - we get this one for both + * types of supported expressions (Var op Const) and (Var op Var). + */ + if (!statext_is_compatible_clause_internal(root, (Node *) var, + relid, attnums)) + return false; + + /* For (Var op Const) we don't get the second Var, and we're done. */ + if (!var2) + return true; + + /* For (Var op Var) check compatibility of the second Var. */ + return statext_is_compatible_clause_internal(root, (Node *) var2, relid, attnums); } @@ -1419,19 +1436,21 @@ statext_clauselist_selectivity(PlannerInfo *root, List *clauses, int varRelid, * examine_opclause_expression * Split expression into Var and Const parts. * - * Attempts to match the arguments to either (Var op Const) or (Const op Var), - * possibly with a RelabelType on top. When the expression matches this form, - * returns true, otherwise returns false. + * Attempts to match the arguments to either (Var op Const) or (Const op Var) + * or (Var op Var), possibly with a RelabelType on top. When the expression + * matches this form, returns true, otherwise returns false. * * Optionally returns pointers to the extracted Var/Const nodes, when passed * non-null pointers (varp, cstp and varonleftp). The varonleftp flag specifies * on which side of the operator we found the Var node. */ bool -examine_opclause_expression(OpExpr *expr, Var **varp, Const **cstp, bool *varonleftp) +examine_opclause_expression(OpExpr *expr, Var **var1p, Var **var2p, + Const **cstp, bool *varonleftp) { - Var *var; - Const *cst; + Var *var1 = NULL; + Var *var2 = NULL; + Const *cst = NULL; bool varonleft; Node *leftop, *rightop; @@ -1451,22 +1470,38 @@ examine_opclause_expression(OpExpr *expr, Var **varp, Const **cstp, bool *varonl if (IsA(leftop, Var) && IsA(rightop, Const)) { - var = (Var *) leftop; + var1 = (Var *) leftop; cst = (Const *) rightop; varonleft = true; } else if (IsA(leftop, Const) && IsA(rightop, Var)) { - var = (Var *) rightop; + var1 = (Var *) rightop; cst = (Const *) leftop; varonleft = false; } + else if (IsA(leftop, Var) && IsA(rightop, Var)) + { + var1 = (Var *) leftop; + var2 = (Var *) rightop; + varonleft = false; + + /* + * Both variables have to be for the same relation (otherwise it's + * a join clause, and we don't deal with those yet. + */ + if (var1->varno != var2->varno) + return false; + } else return false; /* return pointers to the extracted parts if requested */ - if (varp) - *varp = var; + if (var1p) + *var1p = var1; + + if (var2p) + *var2p = var2; if (cstp) *cstp = cst; diff --git a/src/backend/statistics/mcv.c b/src/backend/statistics/mcv.c index 3f42713aa2..97d3083451 100644 --- a/src/backend/statistics/mcv.c +++ b/src/backend/statistics/mcv.c @@ -1581,16 +1581,25 @@ mcv_get_match_bitmap(PlannerInfo *root, List *clauses, /* valid only after examine_opclause_expression returns true */ Var *var; + Var *var2; Const *cst; bool varonleft; fmgr_info(get_opcode(expr->opno), &opproc); - /* extract the var and const from the expression */ - if (examine_opclause_expression(expr, &var, &cst, &varonleft)) + /* extract the vars and const from the expression */ + if (!examine_opclause_expression(expr, &var, &var2, &cst, &varonleft)) + continue; /* XXX Can this actually happen? */ + + /* We should always get at least one Var. */ + Assert(var); + + if (cst) { int idx; + Assert(!var2); + /* match the attribute to a dimension of the statistic */ idx = bms_member_index(keys, var->varattno); @@ -1651,6 +1660,68 @@ mcv_get_match_bitmap(PlannerInfo *root, List *clauses, matches[i] = RESULT_MERGE(matches[i], is_or, match); } } + else + { + int idx; + int idx2; + + Assert(var2); + + /* match the attribute to a dimension of the statistic */ + idx = bms_member_index(keys, var->varattno); + idx2 = bms_member_index(keys, var2->varattno); + + /* + * Walk through the MCV items and evaluate the current clause. + * We can skip items that were already ruled out, and + * terminate if there are no remaining MCV items that might + * possibly match. + */ + for (i = 0; i < mcvlist->nitems; i++) + { + bool match = true; + MCVItem *item = &mcvlist->items[i]; + + /* + * When either of the MCV items is NULL we can treat this + * as a mismatch. We must not call the operator because + * of strictness. + */ + if (item->isnull[idx] || item->isnull[idx2]) + { + matches[i] = RESULT_MERGE(matches[i], is_or, false); + continue; + } + + /* + * Skip MCV items that can't change result in the bitmap. + * Once the value gets false for AND-lists, or true for + * OR-lists, we don't need to look at more clauses. + */ + if (RESULT_IS_FINAL(matches[i], is_or)) + continue; + + /* + * First check whether the constant is below the lower + * boundary (in that case we can skip the bucket, because + * there's no overlap). + * + * We don't store collations used to build the statistics, + * but we can use the collation for the attribute itself, + * as stored in varcollid. We do reset the statistics after + * a type change (including collation change), so this is + * OK. We may need to relax this after allowing extended + * statistics on expressions. + */ + match = DatumGetBool(FunctionCall2Coll(&opproc, + var->varcollid, + item->values[idx], + item->values[idx2])); + + /* update the match bitmap with the result */ + matches[i] = RESULT_MERGE(matches[i], is_or, match); + } + } } else if (IsA(clause, NullTest)) { diff --git a/src/include/statistics/extended_stats_internal.h b/src/include/statistics/extended_stats_internal.h index 5171895bba..804089bc57 100644 --- a/src/include/statistics/extended_stats_internal.h +++ b/src/include/statistics/extended_stats_internal.h @@ -96,7 +96,7 @@ extern SortItem *build_sorted_items(int numrows, int *nitems, HeapTuple *rows, TupleDesc tdesc, MultiSortSupport mss, int numattrs, AttrNumber *attnums); -extern bool examine_opclause_expression(OpExpr *expr, Var **varp, +extern bool examine_opclause_expression(OpExpr *expr, Var **var1p, Var **var2p, Const **cstp, bool *varonleftp); extern Selectivity mcv_clauselist_selectivity(PlannerInfo *root, diff --git a/src/test/regress/expected/stats_ext.out b/src/test/regress/expected/stats_ext.out index 5344b70cf4..4c078ae61f 100644 --- a/src/test/regress/expected/stats_ext.out +++ b/src/test/regress/expected/stats_ext.out @@ -603,6 +603,18 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a = 1 OR b = ' 343 | 200 (1 row) +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a > c'); + estimated | actual +-----------+-------- + 1667 | 3750 +(1 row) + +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a < c'); + estimated | actual +-----------+-------- + 1667 | 0 +(1 row) + -- create statistics CREATE STATISTICS mcv_lists_stats (mcv) ON a, b, c FROM mcv_lists; ANALYZE mcv_lists; @@ -654,6 +666,18 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a = 1 OR b = ' 200 | 200 (1 row) +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a > c'); + estimated | actual +-----------+-------- + 3750 | 3750 +(1 row) + +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a < c'); + estimated | actual +-----------+-------- + 1 | 0 +(1 row) + -- check change of unrelated column type does not reset the MCV statistics ALTER TABLE mcv_lists ALTER COLUMN d TYPE VARCHAR(64); SELECT d.stxdmcv IS NOT NULL @@ -749,6 +773,12 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE b = ''x'' OR d 3750 | 2500 (1 row) +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE b = d'); + estimated | actual +-----------+-------- + 25 | 2500 +(1 row) + -- create statistics CREATE STATISTICS mcv_lists_stats (mcv) ON b, d FROM mcv_lists; ANALYZE mcv_lists; @@ -758,6 +788,12 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE b = ''x'' OR d 2500 | 2500 (1 row) +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE b = d'); + estimated | actual +-----------+-------- + 2500 | 2500 +(1 row) + -- mcv with arrays CREATE TABLE mcv_lists_arrays ( a TEXT[], @@ -808,6 +844,18 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a AND 1094 | 0 (1 row) +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a = b'); + estimated | actual +-----------+-------- + 9950 | 2500 +(1 row) + +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a = b AND b = c'); + estimated | actual +-----------+-------- + 50 | 2500 +(1 row) + CREATE STATISTICS mcv_lists_bool_stats (mcv) ON a, b, c FROM mcv_lists_bool; ANALYZE mcv_lists_bool; @@ -835,6 +883,18 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a AND 1 | 0 (1 row) +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a = b'); + estimated | actual +-----------+-------- + 2500 | 2500 +(1 row) + +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a = b AND b = c'); + estimated | actual +-----------+-------- + 2500 | 2500 +(1 row) + -- check the ability to use multiple MCV lists CREATE TABLE mcv_lists_multi ( a INTEGER, @@ -869,6 +929,12 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = 0 AN 4 | 142 (1 row) +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = b AND c = d'); + estimated | actual +-----------+-------- + 1 | 5000 +(1 row) + -- create separate MCV statistics CREATE STATISTICS mcv_lists_multi_1 (mcv) ON a, b FROM mcv_lists_multi; CREATE STATISTICS mcv_lists_multi_2 (mcv) ON c, d FROM mcv_lists_multi; @@ -891,6 +957,12 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = 0 AN 143 | 142 (1 row) +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = b AND c = d'); + estimated | actual +-----------+-------- + 5000 | 5000 +(1 row) + DROP TABLE mcv_lists_multi; -- Permission tests. Users should not be able to see specific data values in -- the extended statistics, if they lack permission to see those values in diff --git a/src/test/regress/sql/stats_ext.sql b/src/test/regress/sql/stats_ext.sql index fa989fccb0..b7519b275b 100644 --- a/src/test/regress/sql/stats_ext.sql +++ b/src/test/regress/sql/stats_ext.sql @@ -381,6 +381,10 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a = 1 OR b = ' SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a = 1 OR b = ''1'' OR c = 1 OR d IS NOT NULL'); +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a > c'); + +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a < c'); + -- create statistics CREATE STATISTICS mcv_lists_stats (mcv) ON a, b, c FROM mcv_lists; @@ -402,6 +406,10 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a = 1 OR b = ' SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a = 1 OR b = ''1'' OR c = 1 OR d IS NOT NULL'); +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a > c'); + +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a < c'); + -- check change of unrelated column type does not reset the MCV statistics ALTER TABLE mcv_lists ALTER COLUMN d TYPE VARCHAR(64); @@ -473,6 +481,8 @@ ANALYZE mcv_lists; SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE b = ''x'' OR d = ''x'''); +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE b = d'); + -- create statistics CREATE STATISTICS mcv_lists_stats (mcv) ON b, d FROM mcv_lists; @@ -480,6 +490,8 @@ ANALYZE mcv_lists; SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE b = ''x'' OR d = ''x'''); +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE b = d'); + -- mcv with arrays CREATE TABLE mcv_lists_arrays ( a TEXT[], @@ -521,6 +533,10 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a AND SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a AND b AND NOT c'); +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a = b'); + +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a = b AND b = c'); + CREATE STATISTICS mcv_lists_bool_stats (mcv) ON a, b, c FROM mcv_lists_bool; @@ -534,6 +550,10 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a AND SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a AND b AND NOT c'); +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a = b'); + +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a = b AND b = c'); + -- check the ability to use multiple MCV lists CREATE TABLE mcv_lists_multi ( a INTEGER, @@ -556,6 +576,7 @@ ANALYZE mcv_lists_multi; SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = 0 AND b = 0'); SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE c = 0 AND d = 0'); SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = 0 AND b = 0 AND c = 0 AND d = 0'); +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = b AND c = d'); -- create separate MCV statistics CREATE STATISTICS mcv_lists_multi_1 (mcv) ON a, b FROM mcv_lists_multi; @@ -566,6 +587,7 @@ ANALYZE mcv_lists_multi; SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = 0 AND b = 0'); SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE c = 0 AND d = 0'); SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = 0 AND b = 0 AND c = 0 AND d = 0'); +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = b AND c = d'); DROP TABLE mcv_lists_multi; -- 2.21.1 --n6bnrzck2js7zcqs-- ^ permalink raw reply [nested|flat] 6+ messages in thread
* [PATCH 2/3] Support clauses of the form Var op Var @ 2019-11-11 00:34 Tomas Vondra <tv@fuzzy.cz> 0 siblings, 0 replies; 6+ messages in thread From: Tomas Vondra @ 2019-11-11 00:34 UTC (permalink / raw) --- src/backend/statistics/extended_stats.c | 63 ++++++++++++---- src/backend/statistics/mcv.c | 75 ++++++++++++++++++- .../statistics/extended_stats_internal.h | 2 +- src/test/regress/expected/stats_ext.out | 72 ++++++++++++++++++ src/test/regress/sql/stats_ext.sql | 22 ++++++ 5 files changed, 217 insertions(+), 17 deletions(-) diff --git a/src/backend/statistics/extended_stats.c b/src/backend/statistics/extended_stats.c index 24ece6f99c..1872cd4529 100644 --- a/src/backend/statistics/extended_stats.c +++ b/src/backend/statistics/extended_stats.c @@ -986,14 +986,18 @@ statext_is_compatible_clause_internal(PlannerInfo *root, Node *clause, { RangeTblEntry *rte = root->simple_rte_array[relid]; OpExpr *expr = (OpExpr *) clause; - Var *var; + Var *var, + *var2; /* Only expressions with two arguments are considered compatible. */ if (list_length(expr->args) != 2) return false; - /* Check if the expression the right shape (one Var, one Const) */ - if (!examine_opclause_expression(expr, &var, NULL, NULL)) + /* + * Check if the expression the right shape (one Var and one Const, + * or two Vars). + */ + if (!examine_opclause_expression(expr, &var, &var2, NULL, NULL)) return false; /* @@ -1033,7 +1037,20 @@ statext_is_compatible_clause_internal(PlannerInfo *root, Node *clause, !get_func_leakproof(get_opcode(expr->opno))) return false; - return statext_is_compatible_clause_internal(root, (Node *) var, + /* + * Check compatibility of the first Var - we get this one for both + * types of supported expressions (Var op Const) and (Var op Var). + */ + if (!statext_is_compatible_clause_internal(root, (Node *) var, + relid, attnums)) + return false; + + /* For (Var op Const) we don't get the second Var, and we're done. */ + if (!var2) + return true; + + /* For (Var op Var) check compatibility of the second Var. */ + return statext_is_compatible_clause_internal(root, (Node *) var2, relid, attnums); } @@ -1419,19 +1436,21 @@ statext_clauselist_selectivity(PlannerInfo *root, List *clauses, int varRelid, * examine_opclause_expression * Split expression into Var and Const parts. * - * Attempts to match the arguments to either (Var op Const) or (Const op Var), - * possibly with a RelabelType on top. When the expression matches this form, - * returns true, otherwise returns false. + * Attempts to match the arguments to either (Var op Const) or (Const op Var) + * or (Var op Var), possibly with a RelabelType on top. When the expression + * matches this form, returns true, otherwise returns false. * * Optionally returns pointers to the extracted Var/Const nodes, when passed * non-null pointers (varp, cstp and varonleftp). The varonleftp flag specifies * on which side of the operator we found the Var node. */ bool -examine_opclause_expression(OpExpr *expr, Var **varp, Const **cstp, bool *varonleftp) +examine_opclause_expression(OpExpr *expr, Var **var1p, Var **var2p, + Const **cstp, bool *varonleftp) { - Var *var; - Const *cst; + Var *var1 = NULL; + Var *var2 = NULL; + Const *cst = NULL; bool varonleft; Node *leftop, *rightop; @@ -1451,22 +1470,38 @@ examine_opclause_expression(OpExpr *expr, Var **varp, Const **cstp, bool *varonl if (IsA(leftop, Var) && IsA(rightop, Const)) { - var = (Var *) leftop; + var1 = (Var *) leftop; cst = (Const *) rightop; varonleft = true; } else if (IsA(leftop, Const) && IsA(rightop, Var)) { - var = (Var *) rightop; + var1 = (Var *) rightop; cst = (Const *) leftop; varonleft = false; } + else if (IsA(leftop, Var) && IsA(rightop, Var)) + { + var1 = (Var *) leftop; + var2 = (Var *) rightop; + varonleft = false; + + /* + * Both variables have to be for the same relation (otherwise it's + * a join clause, and we don't deal with those yet. + */ + if (var1->varno != var2->varno) + return false; + } else return false; /* return pointers to the extracted parts if requested */ - if (varp) - *varp = var; + if (var1p) + *var1p = var1; + + if (var2p) + *var2p = var2; if (cstp) *cstp = cst; diff --git a/src/backend/statistics/mcv.c b/src/backend/statistics/mcv.c index 3f42713aa2..97d3083451 100644 --- a/src/backend/statistics/mcv.c +++ b/src/backend/statistics/mcv.c @@ -1581,16 +1581,25 @@ mcv_get_match_bitmap(PlannerInfo *root, List *clauses, /* valid only after examine_opclause_expression returns true */ Var *var; + Var *var2; Const *cst; bool varonleft; fmgr_info(get_opcode(expr->opno), &opproc); - /* extract the var and const from the expression */ - if (examine_opclause_expression(expr, &var, &cst, &varonleft)) + /* extract the vars and const from the expression */ + if (!examine_opclause_expression(expr, &var, &var2, &cst, &varonleft)) + continue; /* XXX Can this actually happen? */ + + /* We should always get at least one Var. */ + Assert(var); + + if (cst) { int idx; + Assert(!var2); + /* match the attribute to a dimension of the statistic */ idx = bms_member_index(keys, var->varattno); @@ -1651,6 +1660,68 @@ mcv_get_match_bitmap(PlannerInfo *root, List *clauses, matches[i] = RESULT_MERGE(matches[i], is_or, match); } } + else + { + int idx; + int idx2; + + Assert(var2); + + /* match the attribute to a dimension of the statistic */ + idx = bms_member_index(keys, var->varattno); + idx2 = bms_member_index(keys, var2->varattno); + + /* + * Walk through the MCV items and evaluate the current clause. + * We can skip items that were already ruled out, and + * terminate if there are no remaining MCV items that might + * possibly match. + */ + for (i = 0; i < mcvlist->nitems; i++) + { + bool match = true; + MCVItem *item = &mcvlist->items[i]; + + /* + * When either of the MCV items is NULL we can treat this + * as a mismatch. We must not call the operator because + * of strictness. + */ + if (item->isnull[idx] || item->isnull[idx2]) + { + matches[i] = RESULT_MERGE(matches[i], is_or, false); + continue; + } + + /* + * Skip MCV items that can't change result in the bitmap. + * Once the value gets false for AND-lists, or true for + * OR-lists, we don't need to look at more clauses. + */ + if (RESULT_IS_FINAL(matches[i], is_or)) + continue; + + /* + * First check whether the constant is below the lower + * boundary (in that case we can skip the bucket, because + * there's no overlap). + * + * We don't store collations used to build the statistics, + * but we can use the collation for the attribute itself, + * as stored in varcollid. We do reset the statistics after + * a type change (including collation change), so this is + * OK. We may need to relax this after allowing extended + * statistics on expressions. + */ + match = DatumGetBool(FunctionCall2Coll(&opproc, + var->varcollid, + item->values[idx], + item->values[idx2])); + + /* update the match bitmap with the result */ + matches[i] = RESULT_MERGE(matches[i], is_or, match); + } + } } else if (IsA(clause, NullTest)) { diff --git a/src/include/statistics/extended_stats_internal.h b/src/include/statistics/extended_stats_internal.h index 5171895bba..804089bc57 100644 --- a/src/include/statistics/extended_stats_internal.h +++ b/src/include/statistics/extended_stats_internal.h @@ -96,7 +96,7 @@ extern SortItem *build_sorted_items(int numrows, int *nitems, HeapTuple *rows, TupleDesc tdesc, MultiSortSupport mss, int numattrs, AttrNumber *attnums); -extern bool examine_opclause_expression(OpExpr *expr, Var **varp, +extern bool examine_opclause_expression(OpExpr *expr, Var **var1p, Var **var2p, Const **cstp, bool *varonleftp); extern Selectivity mcv_clauselist_selectivity(PlannerInfo *root, diff --git a/src/test/regress/expected/stats_ext.out b/src/test/regress/expected/stats_ext.out index 5344b70cf4..4c078ae61f 100644 --- a/src/test/regress/expected/stats_ext.out +++ b/src/test/regress/expected/stats_ext.out @@ -603,6 +603,18 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a = 1 OR b = ' 343 | 200 (1 row) +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a > c'); + estimated | actual +-----------+-------- + 1667 | 3750 +(1 row) + +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a < c'); + estimated | actual +-----------+-------- + 1667 | 0 +(1 row) + -- create statistics CREATE STATISTICS mcv_lists_stats (mcv) ON a, b, c FROM mcv_lists; ANALYZE mcv_lists; @@ -654,6 +666,18 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a = 1 OR b = ' 200 | 200 (1 row) +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a > c'); + estimated | actual +-----------+-------- + 3750 | 3750 +(1 row) + +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a < c'); + estimated | actual +-----------+-------- + 1 | 0 +(1 row) + -- check change of unrelated column type does not reset the MCV statistics ALTER TABLE mcv_lists ALTER COLUMN d TYPE VARCHAR(64); SELECT d.stxdmcv IS NOT NULL @@ -749,6 +773,12 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE b = ''x'' OR d 3750 | 2500 (1 row) +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE b = d'); + estimated | actual +-----------+-------- + 25 | 2500 +(1 row) + -- create statistics CREATE STATISTICS mcv_lists_stats (mcv) ON b, d FROM mcv_lists; ANALYZE mcv_lists; @@ -758,6 +788,12 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE b = ''x'' OR d 2500 | 2500 (1 row) +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE b = d'); + estimated | actual +-----------+-------- + 2500 | 2500 +(1 row) + -- mcv with arrays CREATE TABLE mcv_lists_arrays ( a TEXT[], @@ -808,6 +844,18 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a AND 1094 | 0 (1 row) +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a = b'); + estimated | actual +-----------+-------- + 9950 | 2500 +(1 row) + +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a = b AND b = c'); + estimated | actual +-----------+-------- + 50 | 2500 +(1 row) + CREATE STATISTICS mcv_lists_bool_stats (mcv) ON a, b, c FROM mcv_lists_bool; ANALYZE mcv_lists_bool; @@ -835,6 +883,18 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a AND 1 | 0 (1 row) +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a = b'); + estimated | actual +-----------+-------- + 2500 | 2500 +(1 row) + +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a = b AND b = c'); + estimated | actual +-----------+-------- + 2500 | 2500 +(1 row) + -- check the ability to use multiple MCV lists CREATE TABLE mcv_lists_multi ( a INTEGER, @@ -869,6 +929,12 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = 0 AN 4 | 142 (1 row) +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = b AND c = d'); + estimated | actual +-----------+-------- + 1 | 5000 +(1 row) + -- create separate MCV statistics CREATE STATISTICS mcv_lists_multi_1 (mcv) ON a, b FROM mcv_lists_multi; CREATE STATISTICS mcv_lists_multi_2 (mcv) ON c, d FROM mcv_lists_multi; @@ -891,6 +957,12 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = 0 AN 143 | 142 (1 row) +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = b AND c = d'); + estimated | actual +-----------+-------- + 5000 | 5000 +(1 row) + DROP TABLE mcv_lists_multi; -- Permission tests. Users should not be able to see specific data values in -- the extended statistics, if they lack permission to see those values in diff --git a/src/test/regress/sql/stats_ext.sql b/src/test/regress/sql/stats_ext.sql index fa989fccb0..b7519b275b 100644 --- a/src/test/regress/sql/stats_ext.sql +++ b/src/test/regress/sql/stats_ext.sql @@ -381,6 +381,10 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a = 1 OR b = ' SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a = 1 OR b = ''1'' OR c = 1 OR d IS NOT NULL'); +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a > c'); + +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a < c'); + -- create statistics CREATE STATISTICS mcv_lists_stats (mcv) ON a, b, c FROM mcv_lists; @@ -402,6 +406,10 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a = 1 OR b = ' SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a = 1 OR b = ''1'' OR c = 1 OR d IS NOT NULL'); +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a > c'); + +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a < c'); + -- check change of unrelated column type does not reset the MCV statistics ALTER TABLE mcv_lists ALTER COLUMN d TYPE VARCHAR(64); @@ -473,6 +481,8 @@ ANALYZE mcv_lists; SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE b = ''x'' OR d = ''x'''); +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE b = d'); + -- create statistics CREATE STATISTICS mcv_lists_stats (mcv) ON b, d FROM mcv_lists; @@ -480,6 +490,8 @@ ANALYZE mcv_lists; SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE b = ''x'' OR d = ''x'''); +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE b = d'); + -- mcv with arrays CREATE TABLE mcv_lists_arrays ( a TEXT[], @@ -521,6 +533,10 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a AND SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a AND b AND NOT c'); +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a = b'); + +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a = b AND b = c'); + CREATE STATISTICS mcv_lists_bool_stats (mcv) ON a, b, c FROM mcv_lists_bool; @@ -534,6 +550,10 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a AND SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a AND b AND NOT c'); +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a = b'); + +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a = b AND b = c'); + -- check the ability to use multiple MCV lists CREATE TABLE mcv_lists_multi ( a INTEGER, @@ -556,6 +576,7 @@ ANALYZE mcv_lists_multi; SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = 0 AND b = 0'); SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE c = 0 AND d = 0'); SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = 0 AND b = 0 AND c = 0 AND d = 0'); +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = b AND c = d'); -- create separate MCV statistics CREATE STATISTICS mcv_lists_multi_1 (mcv) ON a, b FROM mcv_lists_multi; @@ -566,6 +587,7 @@ ANALYZE mcv_lists_multi; SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = 0 AND b = 0'); SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE c = 0 AND d = 0'); SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = 0 AND b = 0 AND c = 0 AND d = 0'); +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = b AND c = d'); DROP TABLE mcv_lists_multi; -- 2.21.1 --mxrkhfy6o2lpe2eo Content-Type: text/plain; charset=us-ascii Content-Disposition: attachment; filename="0003-Support-for-extended-statistics-on-expressi-20200306.patch" ^ permalink raw reply [nested|flat] 6+ messages in thread
* [PATCH 2/3] Support clauses of the form Var op Var @ 2019-11-11 00:34 Tomas Vondra <tv@fuzzy.cz> 0 siblings, 0 replies; 6+ messages in thread From: Tomas Vondra @ 2019-11-11 00:34 UTC (permalink / raw) --- src/backend/statistics/extended_stats.c | 63 ++++++++++++---- src/backend/statistics/mcv.c | 75 ++++++++++++++++++- .../statistics/extended_stats_internal.h | 2 +- src/test/regress/expected/stats_ext.out | 72 ++++++++++++++++++ src/test/regress/sql/stats_ext.sql | 22 ++++++ 5 files changed, 217 insertions(+), 17 deletions(-) diff --git a/src/backend/statistics/extended_stats.c b/src/backend/statistics/extended_stats.c index 24ece6f99c..1872cd4529 100644 --- a/src/backend/statistics/extended_stats.c +++ b/src/backend/statistics/extended_stats.c @@ -986,14 +986,18 @@ statext_is_compatible_clause_internal(PlannerInfo *root, Node *clause, { RangeTblEntry *rte = root->simple_rte_array[relid]; OpExpr *expr = (OpExpr *) clause; - Var *var; + Var *var, + *var2; /* Only expressions with two arguments are considered compatible. */ if (list_length(expr->args) != 2) return false; - /* Check if the expression the right shape (one Var, one Const) */ - if (!examine_opclause_expression(expr, &var, NULL, NULL)) + /* + * Check if the expression the right shape (one Var and one Const, + * or two Vars). + */ + if (!examine_opclause_expression(expr, &var, &var2, NULL, NULL)) return false; /* @@ -1033,7 +1037,20 @@ statext_is_compatible_clause_internal(PlannerInfo *root, Node *clause, !get_func_leakproof(get_opcode(expr->opno))) return false; - return statext_is_compatible_clause_internal(root, (Node *) var, + /* + * Check compatibility of the first Var - we get this one for both + * types of supported expressions (Var op Const) and (Var op Var). + */ + if (!statext_is_compatible_clause_internal(root, (Node *) var, + relid, attnums)) + return false; + + /* For (Var op Const) we don't get the second Var, and we're done. */ + if (!var2) + return true; + + /* For (Var op Var) check compatibility of the second Var. */ + return statext_is_compatible_clause_internal(root, (Node *) var2, relid, attnums); } @@ -1419,19 +1436,21 @@ statext_clauselist_selectivity(PlannerInfo *root, List *clauses, int varRelid, * examine_opclause_expression * Split expression into Var and Const parts. * - * Attempts to match the arguments to either (Var op Const) or (Const op Var), - * possibly with a RelabelType on top. When the expression matches this form, - * returns true, otherwise returns false. + * Attempts to match the arguments to either (Var op Const) or (Const op Var) + * or (Var op Var), possibly with a RelabelType on top. When the expression + * matches this form, returns true, otherwise returns false. * * Optionally returns pointers to the extracted Var/Const nodes, when passed * non-null pointers (varp, cstp and varonleftp). The varonleftp flag specifies * on which side of the operator we found the Var node. */ bool -examine_opclause_expression(OpExpr *expr, Var **varp, Const **cstp, bool *varonleftp) +examine_opclause_expression(OpExpr *expr, Var **var1p, Var **var2p, + Const **cstp, bool *varonleftp) { - Var *var; - Const *cst; + Var *var1 = NULL; + Var *var2 = NULL; + Const *cst = NULL; bool varonleft; Node *leftop, *rightop; @@ -1451,22 +1470,38 @@ examine_opclause_expression(OpExpr *expr, Var **varp, Const **cstp, bool *varonl if (IsA(leftop, Var) && IsA(rightop, Const)) { - var = (Var *) leftop; + var1 = (Var *) leftop; cst = (Const *) rightop; varonleft = true; } else if (IsA(leftop, Const) && IsA(rightop, Var)) { - var = (Var *) rightop; + var1 = (Var *) rightop; cst = (Const *) leftop; varonleft = false; } + else if (IsA(leftop, Var) && IsA(rightop, Var)) + { + var1 = (Var *) leftop; + var2 = (Var *) rightop; + varonleft = false; + + /* + * Both variables have to be for the same relation (otherwise it's + * a join clause, and we don't deal with those yet. + */ + if (var1->varno != var2->varno) + return false; + } else return false; /* return pointers to the extracted parts if requested */ - if (varp) - *varp = var; + if (var1p) + *var1p = var1; + + if (var2p) + *var2p = var2; if (cstp) *cstp = cst; diff --git a/src/backend/statistics/mcv.c b/src/backend/statistics/mcv.c index 3f42713aa2..97d3083451 100644 --- a/src/backend/statistics/mcv.c +++ b/src/backend/statistics/mcv.c @@ -1581,16 +1581,25 @@ mcv_get_match_bitmap(PlannerInfo *root, List *clauses, /* valid only after examine_opclause_expression returns true */ Var *var; + Var *var2; Const *cst; bool varonleft; fmgr_info(get_opcode(expr->opno), &opproc); - /* extract the var and const from the expression */ - if (examine_opclause_expression(expr, &var, &cst, &varonleft)) + /* extract the vars and const from the expression */ + if (!examine_opclause_expression(expr, &var, &var2, &cst, &varonleft)) + continue; /* XXX Can this actually happen? */ + + /* We should always get at least one Var. */ + Assert(var); + + if (cst) { int idx; + Assert(!var2); + /* match the attribute to a dimension of the statistic */ idx = bms_member_index(keys, var->varattno); @@ -1651,6 +1660,68 @@ mcv_get_match_bitmap(PlannerInfo *root, List *clauses, matches[i] = RESULT_MERGE(matches[i], is_or, match); } } + else + { + int idx; + int idx2; + + Assert(var2); + + /* match the attribute to a dimension of the statistic */ + idx = bms_member_index(keys, var->varattno); + idx2 = bms_member_index(keys, var2->varattno); + + /* + * Walk through the MCV items and evaluate the current clause. + * We can skip items that were already ruled out, and + * terminate if there are no remaining MCV items that might + * possibly match. + */ + for (i = 0; i < mcvlist->nitems; i++) + { + bool match = true; + MCVItem *item = &mcvlist->items[i]; + + /* + * When either of the MCV items is NULL we can treat this + * as a mismatch. We must not call the operator because + * of strictness. + */ + if (item->isnull[idx] || item->isnull[idx2]) + { + matches[i] = RESULT_MERGE(matches[i], is_or, false); + continue; + } + + /* + * Skip MCV items that can't change result in the bitmap. + * Once the value gets false for AND-lists, or true for + * OR-lists, we don't need to look at more clauses. + */ + if (RESULT_IS_FINAL(matches[i], is_or)) + continue; + + /* + * First check whether the constant is below the lower + * boundary (in that case we can skip the bucket, because + * there's no overlap). + * + * We don't store collations used to build the statistics, + * but we can use the collation for the attribute itself, + * as stored in varcollid. We do reset the statistics after + * a type change (including collation change), so this is + * OK. We may need to relax this after allowing extended + * statistics on expressions. + */ + match = DatumGetBool(FunctionCall2Coll(&opproc, + var->varcollid, + item->values[idx], + item->values[idx2])); + + /* update the match bitmap with the result */ + matches[i] = RESULT_MERGE(matches[i], is_or, match); + } + } } else if (IsA(clause, NullTest)) { diff --git a/src/include/statistics/extended_stats_internal.h b/src/include/statistics/extended_stats_internal.h index 5171895bba..804089bc57 100644 --- a/src/include/statistics/extended_stats_internal.h +++ b/src/include/statistics/extended_stats_internal.h @@ -96,7 +96,7 @@ extern SortItem *build_sorted_items(int numrows, int *nitems, HeapTuple *rows, TupleDesc tdesc, MultiSortSupport mss, int numattrs, AttrNumber *attnums); -extern bool examine_opclause_expression(OpExpr *expr, Var **varp, +extern bool examine_opclause_expression(OpExpr *expr, Var **var1p, Var **var2p, Const **cstp, bool *varonleftp); extern Selectivity mcv_clauselist_selectivity(PlannerInfo *root, diff --git a/src/test/regress/expected/stats_ext.out b/src/test/regress/expected/stats_ext.out index 5344b70cf4..4c078ae61f 100644 --- a/src/test/regress/expected/stats_ext.out +++ b/src/test/regress/expected/stats_ext.out @@ -603,6 +603,18 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a = 1 OR b = ' 343 | 200 (1 row) +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a > c'); + estimated | actual +-----------+-------- + 1667 | 3750 +(1 row) + +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a < c'); + estimated | actual +-----------+-------- + 1667 | 0 +(1 row) + -- create statistics CREATE STATISTICS mcv_lists_stats (mcv) ON a, b, c FROM mcv_lists; ANALYZE mcv_lists; @@ -654,6 +666,18 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a = 1 OR b = ' 200 | 200 (1 row) +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a > c'); + estimated | actual +-----------+-------- + 3750 | 3750 +(1 row) + +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a < c'); + estimated | actual +-----------+-------- + 1 | 0 +(1 row) + -- check change of unrelated column type does not reset the MCV statistics ALTER TABLE mcv_lists ALTER COLUMN d TYPE VARCHAR(64); SELECT d.stxdmcv IS NOT NULL @@ -749,6 +773,12 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE b = ''x'' OR d 3750 | 2500 (1 row) +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE b = d'); + estimated | actual +-----------+-------- + 25 | 2500 +(1 row) + -- create statistics CREATE STATISTICS mcv_lists_stats (mcv) ON b, d FROM mcv_lists; ANALYZE mcv_lists; @@ -758,6 +788,12 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE b = ''x'' OR d 2500 | 2500 (1 row) +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE b = d'); + estimated | actual +-----------+-------- + 2500 | 2500 +(1 row) + -- mcv with arrays CREATE TABLE mcv_lists_arrays ( a TEXT[], @@ -808,6 +844,18 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a AND 1094 | 0 (1 row) +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a = b'); + estimated | actual +-----------+-------- + 9950 | 2500 +(1 row) + +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a = b AND b = c'); + estimated | actual +-----------+-------- + 50 | 2500 +(1 row) + CREATE STATISTICS mcv_lists_bool_stats (mcv) ON a, b, c FROM mcv_lists_bool; ANALYZE mcv_lists_bool; @@ -835,6 +883,18 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a AND 1 | 0 (1 row) +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a = b'); + estimated | actual +-----------+-------- + 2500 | 2500 +(1 row) + +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a = b AND b = c'); + estimated | actual +-----------+-------- + 2500 | 2500 +(1 row) + -- check the ability to use multiple MCV lists CREATE TABLE mcv_lists_multi ( a INTEGER, @@ -869,6 +929,12 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = 0 AN 4 | 142 (1 row) +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = b AND c = d'); + estimated | actual +-----------+-------- + 1 | 5000 +(1 row) + -- create separate MCV statistics CREATE STATISTICS mcv_lists_multi_1 (mcv) ON a, b FROM mcv_lists_multi; CREATE STATISTICS mcv_lists_multi_2 (mcv) ON c, d FROM mcv_lists_multi; @@ -891,6 +957,12 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = 0 AN 143 | 142 (1 row) +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = b AND c = d'); + estimated | actual +-----------+-------- + 5000 | 5000 +(1 row) + DROP TABLE mcv_lists_multi; -- Permission tests. Users should not be able to see specific data values in -- the extended statistics, if they lack permission to see those values in diff --git a/src/test/regress/sql/stats_ext.sql b/src/test/regress/sql/stats_ext.sql index fa989fccb0..b7519b275b 100644 --- a/src/test/regress/sql/stats_ext.sql +++ b/src/test/regress/sql/stats_ext.sql @@ -381,6 +381,10 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a = 1 OR b = ' SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a = 1 OR b = ''1'' OR c = 1 OR d IS NOT NULL'); +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a > c'); + +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a < c'); + -- create statistics CREATE STATISTICS mcv_lists_stats (mcv) ON a, b, c FROM mcv_lists; @@ -402,6 +406,10 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a = 1 OR b = ' SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a = 1 OR b = ''1'' OR c = 1 OR d IS NOT NULL'); +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a > c'); + +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a < c'); + -- check change of unrelated column type does not reset the MCV statistics ALTER TABLE mcv_lists ALTER COLUMN d TYPE VARCHAR(64); @@ -473,6 +481,8 @@ ANALYZE mcv_lists; SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE b = ''x'' OR d = ''x'''); +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE b = d'); + -- create statistics CREATE STATISTICS mcv_lists_stats (mcv) ON b, d FROM mcv_lists; @@ -480,6 +490,8 @@ ANALYZE mcv_lists; SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE b = ''x'' OR d = ''x'''); +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE b = d'); + -- mcv with arrays CREATE TABLE mcv_lists_arrays ( a TEXT[], @@ -521,6 +533,10 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a AND SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a AND b AND NOT c'); +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a = b'); + +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a = b AND b = c'); + CREATE STATISTICS mcv_lists_bool_stats (mcv) ON a, b, c FROM mcv_lists_bool; @@ -534,6 +550,10 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a AND SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a AND b AND NOT c'); +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a = b'); + +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a = b AND b = c'); + -- check the ability to use multiple MCV lists CREATE TABLE mcv_lists_multi ( a INTEGER, @@ -556,6 +576,7 @@ ANALYZE mcv_lists_multi; SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = 0 AND b = 0'); SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE c = 0 AND d = 0'); SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = 0 AND b = 0 AND c = 0 AND d = 0'); +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = b AND c = d'); -- create separate MCV statistics CREATE STATISTICS mcv_lists_multi_1 (mcv) ON a, b FROM mcv_lists_multi; @@ -566,6 +587,7 @@ ANALYZE mcv_lists_multi; SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = 0 AND b = 0'); SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE c = 0 AND d = 0'); SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = 0 AND b = 0 AND c = 0 AND d = 0'); +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = b AND c = d'); DROP TABLE mcv_lists_multi; -- 2.21.1 --n6bnrzck2js7zcqs-- ^ permalink raw reply [nested|flat] 6+ messages in thread
* [PATCH 4/4] Support clauses of the form Var op Var @ 2020-03-08 22:27 Tomas Vondra <tv@fuzzy.cz> 0 siblings, 0 replies; 6+ messages in thread From: Tomas Vondra @ 2020-03-08 22:27 UTC (permalink / raw) --- src/backend/statistics/extended_stats.c | 63 ++++++++++++---- src/backend/statistics/mcv.c | 75 ++++++++++++++++++- .../statistics/extended_stats_internal.h | 2 +- src/test/regress/expected/stats_ext.out | 72 ++++++++++++++++++ src/test/regress/sql/stats_ext.sql | 22 ++++++ 5 files changed, 217 insertions(+), 17 deletions(-) diff --git a/src/backend/statistics/extended_stats.c b/src/backend/statistics/extended_stats.c index daf95ff437..ddcb5d2955 100644 --- a/src/backend/statistics/extended_stats.c +++ b/src/backend/statistics/extended_stats.c @@ -986,14 +986,18 @@ statext_is_compatible_clause_internal(PlannerInfo *root, Node *clause, { RangeTblEntry *rte = root->simple_rte_array[relid]; OpExpr *expr = (OpExpr *) clause; - Var *var; + Var *var, + *var2; /* Only expressions with two arguments are considered compatible. */ if (list_length(expr->args) != 2) return false; - /* Check if the expression the right shape (one Var, one Const) */ - if (!examine_opclause_expression(expr, &var, NULL, NULL)) + /* + * Check if the expression the right shape (one Var and one Const, + * or two Vars). + */ + if (!examine_opclause_expression(expr, &var, &var2, NULL, NULL)) return false; /* @@ -1033,7 +1037,20 @@ statext_is_compatible_clause_internal(PlannerInfo *root, Node *clause, !get_func_leakproof(get_opcode(expr->opno))) return false; - return statext_is_compatible_clause_internal(root, (Node *) var, + /* + * Check compatibility of the first Var - we get this one for both + * types of supported expressions (Var op Const) and (Var op Var). + */ + if (!statext_is_compatible_clause_internal(root, (Node *) var, + relid, attnums)) + return false; + + /* For (Var op Const) we don't get the second Var, and we're done. */ + if (!var2) + return true; + + /* For (Var op Var) check compatibility of the second Var. */ + return statext_is_compatible_clause_internal(root, (Node *) var2, relid, attnums); } @@ -1422,19 +1439,21 @@ statext_clauselist_selectivity(PlannerInfo *root, List *clauses, int varRelid, * examine_opclause_expression * Split expression into Var and Const parts. * - * Attempts to match the arguments to either (Var op Const) or (Const op Var), - * possibly with a RelabelType on top. When the expression matches this form, - * returns true, otherwise returns false. + * Attempts to match the arguments to either (Var op Const) or (Const op Var) + * or (Var op Var), possibly with a RelabelType on top. When the expression + * matches this form, returns true, otherwise returns false. * * Optionally returns pointers to the extracted Var/Const nodes, when passed * non-null pointers (varp, cstp and varonleftp). The varonleftp flag specifies * on which side of the operator we found the Var node. */ bool -examine_opclause_expression(OpExpr *expr, Var **varp, Const **cstp, bool *varonleftp) +examine_opclause_expression(OpExpr *expr, Var **var1p, Var **var2p, + Const **cstp, bool *varonleftp) { - Var *var; - Const *cst; + Var *var1 = NULL; + Var *var2 = NULL; + Const *cst = NULL; bool varonleft; Node *leftop, *rightop; @@ -1454,22 +1473,38 @@ examine_opclause_expression(OpExpr *expr, Var **varp, Const **cstp, bool *varonl if (IsA(leftop, Var) && IsA(rightop, Const)) { - var = (Var *) leftop; + var1 = (Var *) leftop; cst = (Const *) rightop; varonleft = true; } else if (IsA(leftop, Const) && IsA(rightop, Var)) { - var = (Var *) rightop; + var1 = (Var *) rightop; cst = (Const *) leftop; varonleft = false; } + else if (IsA(leftop, Var) && IsA(rightop, Var)) + { + var1 = (Var *) leftop; + var2 = (Var *) rightop; + varonleft = false; + + /* + * Both variables have to be for the same relation (otherwise it's + * a join clause, and we don't deal with those yet. + */ + if (var1->varno != var2->varno) + return false; + } else return false; /* return pointers to the extracted parts if requested */ - if (varp) - *varp = var; + if (var1p) + *var1p = var1; + + if (var2p) + *var2p = var2; if (cstp) *cstp = cst; diff --git a/src/backend/statistics/mcv.c b/src/backend/statistics/mcv.c index 3f42713aa2..97d3083451 100644 --- a/src/backend/statistics/mcv.c +++ b/src/backend/statistics/mcv.c @@ -1581,16 +1581,25 @@ mcv_get_match_bitmap(PlannerInfo *root, List *clauses, /* valid only after examine_opclause_expression returns true */ Var *var; + Var *var2; Const *cst; bool varonleft; fmgr_info(get_opcode(expr->opno), &opproc); - /* extract the var and const from the expression */ - if (examine_opclause_expression(expr, &var, &cst, &varonleft)) + /* extract the vars and const from the expression */ + if (!examine_opclause_expression(expr, &var, &var2, &cst, &varonleft)) + continue; /* XXX Can this actually happen? */ + + /* We should always get at least one Var. */ + Assert(var); + + if (cst) { int idx; + Assert(!var2); + /* match the attribute to a dimension of the statistic */ idx = bms_member_index(keys, var->varattno); @@ -1651,6 +1660,68 @@ mcv_get_match_bitmap(PlannerInfo *root, List *clauses, matches[i] = RESULT_MERGE(matches[i], is_or, match); } } + else + { + int idx; + int idx2; + + Assert(var2); + + /* match the attribute to a dimension of the statistic */ + idx = bms_member_index(keys, var->varattno); + idx2 = bms_member_index(keys, var2->varattno); + + /* + * Walk through the MCV items and evaluate the current clause. + * We can skip items that were already ruled out, and + * terminate if there are no remaining MCV items that might + * possibly match. + */ + for (i = 0; i < mcvlist->nitems; i++) + { + bool match = true; + MCVItem *item = &mcvlist->items[i]; + + /* + * When either of the MCV items is NULL we can treat this + * as a mismatch. We must not call the operator because + * of strictness. + */ + if (item->isnull[idx] || item->isnull[idx2]) + { + matches[i] = RESULT_MERGE(matches[i], is_or, false); + continue; + } + + /* + * Skip MCV items that can't change result in the bitmap. + * Once the value gets false for AND-lists, or true for + * OR-lists, we don't need to look at more clauses. + */ + if (RESULT_IS_FINAL(matches[i], is_or)) + continue; + + /* + * First check whether the constant is below the lower + * boundary (in that case we can skip the bucket, because + * there's no overlap). + * + * We don't store collations used to build the statistics, + * but we can use the collation for the attribute itself, + * as stored in varcollid. We do reset the statistics after + * a type change (including collation change), so this is + * OK. We may need to relax this after allowing extended + * statistics on expressions. + */ + match = DatumGetBool(FunctionCall2Coll(&opproc, + var->varcollid, + item->values[idx], + item->values[idx2])); + + /* update the match bitmap with the result */ + matches[i] = RESULT_MERGE(matches[i], is_or, match); + } + } } else if (IsA(clause, NullTest)) { diff --git a/src/include/statistics/extended_stats_internal.h b/src/include/statistics/extended_stats_internal.h index 5171895bba..804089bc57 100644 --- a/src/include/statistics/extended_stats_internal.h +++ b/src/include/statistics/extended_stats_internal.h @@ -96,7 +96,7 @@ extern SortItem *build_sorted_items(int numrows, int *nitems, HeapTuple *rows, TupleDesc tdesc, MultiSortSupport mss, int numattrs, AttrNumber *attnums); -extern bool examine_opclause_expression(OpExpr *expr, Var **varp, +extern bool examine_opclause_expression(OpExpr *expr, Var **var1p, Var **var2p, Const **cstp, bool *varonleftp); extern Selectivity mcv_clauselist_selectivity(PlannerInfo *root, diff --git a/src/test/regress/expected/stats_ext.out b/src/test/regress/expected/stats_ext.out index 383465e8cb..3eb1804cf3 100644 --- a/src/test/regress/expected/stats_ext.out +++ b/src/test/regress/expected/stats_ext.out @@ -603,6 +603,18 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a = 1 OR b = ' 343 | 200 (1 row) +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a > c'); + estimated | actual +-----------+-------- + 1667 | 3750 +(1 row) + +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a < c'); + estimated | actual +-----------+-------- + 1667 | 0 +(1 row) + -- create statistics CREATE STATISTICS mcv_lists_stats (mcv) ON a, b, c FROM mcv_lists; ANALYZE mcv_lists; @@ -654,6 +666,18 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a = 1 OR b = ' 200 | 200 (1 row) +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a > c'); + estimated | actual +-----------+-------- + 3750 | 3750 +(1 row) + +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a < c'); + estimated | actual +-----------+-------- + 1 | 0 +(1 row) + -- check change of unrelated column type does not reset the MCV statistics ALTER TABLE mcv_lists ALTER COLUMN d TYPE VARCHAR(64); SELECT d.stxdmcv IS NOT NULL @@ -749,6 +773,12 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE b = ''x'' OR d 3750 | 2500 (1 row) +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE b = d'); + estimated | actual +-----------+-------- + 25 | 2500 +(1 row) + -- create statistics CREATE STATISTICS mcv_lists_stats (mcv) ON b, d FROM mcv_lists; ANALYZE mcv_lists; @@ -758,6 +788,12 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE b = ''x'' OR d 2500 | 2500 (1 row) +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE b = d'); + estimated | actual +-----------+-------- + 2500 | 2500 +(1 row) + -- mcv with arrays CREATE TABLE mcv_lists_arrays ( a TEXT[], @@ -808,6 +844,18 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a AND 1094 | 0 (1 row) +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a = b'); + estimated | actual +-----------+-------- + 9950 | 2500 +(1 row) + +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a = b AND b = c'); + estimated | actual +-----------+-------- + 50 | 2500 +(1 row) + CREATE STATISTICS mcv_lists_bool_stats (mcv) ON a, b, c FROM mcv_lists_bool; ANALYZE mcv_lists_bool; @@ -835,6 +883,18 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a AND 1 | 0 (1 row) +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a = b'); + estimated | actual +-----------+-------- + 2500 | 2500 +(1 row) + +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a = b AND b = c'); + estimated | actual +-----------+-------- + 2500 | 2500 +(1 row) + -- check the ability to use multiple MCV lists CREATE TABLE mcv_lists_multi ( a INTEGER, @@ -893,6 +953,12 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = 0 OR 2649 | 1572 (1 row) +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = b AND c = d'); + estimated | actual +-----------+-------- + 1 | 5000 +(1 row) + -- create separate MCV statistics CREATE STATISTICS mcv_lists_multi_1 (mcv) ON a, b FROM mcv_lists_multi; CREATE STATISTICS mcv_lists_multi_2 (mcv) ON c, d FROM mcv_lists_multi; @@ -939,6 +1005,12 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = 0 OR 1571 | 1572 (1 row) +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = b AND c = d'); + estimated | actual +-----------+-------- + 5000 | 5000 +(1 row) + DROP TABLE mcv_lists_multi; -- Permission tests. Users should not be able to see specific data values in -- the extended statistics, if they lack permission to see those values in diff --git a/src/test/regress/sql/stats_ext.sql b/src/test/regress/sql/stats_ext.sql index 6fd8b016bd..42b67f7cde 100644 --- a/src/test/regress/sql/stats_ext.sql +++ b/src/test/regress/sql/stats_ext.sql @@ -381,6 +381,10 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a = 1 OR b = ' SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a = 1 OR b = ''1'' OR c = 1 OR d IS NOT NULL'); +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a > c'); + +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a < c'); + -- create statistics CREATE STATISTICS mcv_lists_stats (mcv) ON a, b, c FROM mcv_lists; @@ -402,6 +406,10 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a = 1 OR b = ' SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a = 1 OR b = ''1'' OR c = 1 OR d IS NOT NULL'); +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a > c'); + +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a < c'); + -- check change of unrelated column type does not reset the MCV statistics ALTER TABLE mcv_lists ALTER COLUMN d TYPE VARCHAR(64); @@ -473,6 +481,8 @@ ANALYZE mcv_lists; SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE b = ''x'' OR d = ''x'''); +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE b = d'); + -- create statistics CREATE STATISTICS mcv_lists_stats (mcv) ON b, d FROM mcv_lists; @@ -480,6 +490,8 @@ ANALYZE mcv_lists; SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE b = ''x'' OR d = ''x'''); +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE b = d'); + -- mcv with arrays CREATE TABLE mcv_lists_arrays ( a TEXT[], @@ -521,6 +533,10 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a AND SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a AND b AND NOT c'); +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a = b'); + +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a = b AND b = c'); + CREATE STATISTICS mcv_lists_bool_stats (mcv) ON a, b, c FROM mcv_lists_bool; @@ -534,6 +550,10 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a AND SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a AND b AND NOT c'); +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a = b'); + +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a = b AND b = c'); + -- check the ability to use multiple MCV lists CREATE TABLE mcv_lists_multi ( a INTEGER, @@ -560,6 +580,7 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE b = 0 OR SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = 0 AND b = 0 AND c = 0 AND d = 0'); SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE (a = 0 AND b = 0) OR (c = 0 AND d = 0)'); SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = 0 OR b = 0 OR c = 0 OR d = 0'); +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = b AND c = d'); -- create separate MCV statistics CREATE STATISTICS mcv_lists_multi_1 (mcv) ON a, b FROM mcv_lists_multi; @@ -574,6 +595,7 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE b = 0 OR SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = 0 AND b = 0 AND c = 0 AND d = 0'); SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE (a = 0 AND b = 0) OR (c = 0 AND d = 0)'); SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = 0 OR b = 0 OR c = 0 OR d = 0'); +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = b AND c = d'); DROP TABLE mcv_lists_multi; -- 2.21.1 --vcvacfll7i2xqkl4-- ^ permalink raw reply [nested|flat] 6+ messages in thread
* [PATCH 2/2] Support clauses of the form Var op Var @ 2020-03-17 01:57 Tomas Vondra <tv@fuzzy.cz> 0 siblings, 0 replies; 6+ messages in thread From: Tomas Vondra @ 2020-03-17 01:57 UTC (permalink / raw) --- src/backend/statistics/extended_stats.c | 67 ++++++++++++----- src/backend/statistics/mcv.c | 71 +++++++++++++++++- .../statistics/extended_stats_internal.h | 2 +- src/test/regress/expected/stats_ext.out | 72 +++++++++++++++++++ src/test/regress/sql/stats_ext.sql | 22 ++++++ 5 files changed, 215 insertions(+), 19 deletions(-) diff --git a/src/backend/statistics/extended_stats.c b/src/backend/statistics/extended_stats.c index 93d67791c5..f8947d9097 100644 --- a/src/backend/statistics/extended_stats.c +++ b/src/backend/statistics/extended_stats.c @@ -987,14 +987,18 @@ statext_is_compatible_clause_internal(PlannerInfo *root, Node *clause, { RangeTblEntry *rte = root->simple_rte_array[relid]; OpExpr *expr = (OpExpr *) clause; - Var *var; + Var *var, + *var2; /* Only expressions with two arguments are considered compatible. */ if (list_length(expr->args) != 2) return false; - /* Check if the expression has the right shape (one Var, one Const) */ - if (!examine_clause_args(expr->args, &var, NULL, NULL)) + /* + * Check if the expression has the right shape (one Var and one Const, + * or two Vars). + */ + if (!examine_clause_args(expr->args, &var, &var2, NULL, NULL)) return false; /* @@ -1034,7 +1038,20 @@ statext_is_compatible_clause_internal(PlannerInfo *root, Node *clause, !get_func_leakproof(get_opcode(expr->opno))) return false; - return statext_is_compatible_clause_internal(root, (Node *) var, + /* + * Check compatibility of the first Var - we get this one for both + * types of supported expressions (Var op Const) and (Var op Var). + */ + if (!statext_is_compatible_clause_internal(root, (Node *) var, + relid, attnums)) + return false; + + /* For (Var op Const) we don't get the second Var, and we're done. */ + if (!var2) + return true; + + /* For (Var op Var) check compatibility of the second Var. */ + return statext_is_compatible_clause_internal(root, (Node *) var2, relid, attnums); } @@ -1050,7 +1067,7 @@ statext_is_compatible_clause_internal(PlannerInfo *root, Node *clause, return false; /* Check if the expression has the right shape (one Var, one Const) */ - if (!examine_clause_args(expr->args, &var, NULL, NULL)) + if (!examine_clause_args(expr->args, &var, NULL, NULL, NULL)) return false; /* @@ -1456,22 +1473,24 @@ statext_clauselist_selectivity(PlannerInfo *root, List *clauses, int varRelid, } /* - * examine_opclause_expression + * examine_clause_args * Split expression into Var and Const parts. * - * Attempts to match the arguments to either (Var op Const) or (Const op Var), - * possibly with a RelabelType on top. When the expression matches this form, - * returns true, otherwise returns false. + * Attempts to match the arguments to either (Var op Const) or (Const op Var) + * or (Var op Var), possibly with a RelabelType on top. When the expression + * matches this form, returns true, otherwise returns false. * * Optionally returns pointers to the extracted Var/Const nodes, when passed * non-null pointers (varp, cstp and varonleftp). The varonleftp flag specifies * on which side of the operator we found the Var node. */ bool -examine_clause_args(List *args, Var **varp, Const **cstp, bool *varonleftp) +examine_clause_args(List *args, Var **var1p, Var **var2p, Const **cstp, + bool *varonleftp) { - Var *var; - Const *cst; + Var *var1 = NULL; + Var *var2 = NULL; + Const *cst = NULL; bool varonleft; Node *leftop, *rightop; @@ -1491,22 +1510,38 @@ examine_clause_args(List *args, Var **varp, Const **cstp, bool *varonleftp) if (IsA(leftop, Var) && IsA(rightop, Const)) { - var = (Var *) leftop; + var1 = (Var *) leftop; cst = (Const *) rightop; varonleft = true; } else if (IsA(leftop, Const) && IsA(rightop, Var)) { - var = (Var *) rightop; + var1 = (Var *) rightop; cst = (Const *) leftop; varonleft = false; } + else if (IsA(leftop, Var) && IsA(rightop, Var)) + { + var1 = (Var *) leftop; + var2 = (Var *) rightop; + varonleft = false; + + /* + * Both variables have to be for the same relation (otherwise it's + * a join clause, and we don't deal with those yet. + */ + if (var1->varno != var2->varno) + return false; + } else return false; /* return pointers to the extracted parts if requested */ - if (varp) - *varp = var; + if (var1p) + *var1p = var1; + + if (var2p) + *var2p = var2; if (cstp) *cstp = cst; diff --git a/src/backend/statistics/mcv.c b/src/backend/statistics/mcv.c index 343011178b..3e58d36d68 100644 --- a/src/backend/statistics/mcv.c +++ b/src/backend/statistics/mcv.c @@ -1581,13 +1581,17 @@ mcv_get_match_bitmap(PlannerInfo *root, List *clauses, /* valid only after examine_clause_args returns true */ Var *var; + Var *var2; Const *cst; bool varonleft; fmgr_info(get_opcode(expr->opno), &opproc); /* extract the var and const from the expression */ - if (examine_clause_args(expr->args, &var, &cst, &varonleft)) + if (!examine_clause_args(expr->args, &var, &var2, &cst, &varonleft)) + continue; + + if (cst) /* Var op Const */ { int idx; @@ -1651,6 +1655,68 @@ mcv_get_match_bitmap(PlannerInfo *root, List *clauses, matches[i] = RESULT_MERGE(matches[i], is_or, match); } } + else /* Var op Var */ + { + int idx; + int idx2; + + Assert(var2); + + /* match the attribute to a dimension of the statistic */ + idx = bms_member_index(keys, var->varattno); + idx2 = bms_member_index(keys, var2->varattno); + + /* + * Walk through the MCV items and evaluate the current clause. + * We can skip items that were already ruled out, and + * terminate if there are no remaining MCV items that might + * possibly match. + */ + for (i = 0; i < mcvlist->nitems; i++) + { + bool match = true; + MCVItem *item = &mcvlist->items[i]; + + /* + * When either of the MCV items is NULL we can treat this + * as a mismatch. We must not call the operator because + * of strictness. + */ + if (item->isnull[idx] || item->isnull[idx2]) + { + matches[i] = RESULT_MERGE(matches[i], is_or, false); + continue; + } + + /* + * Skip MCV items that can't change result in the bitmap. + * Once the value gets false for AND-lists, or true for + * OR-lists, we don't need to look at more clauses. + */ + if (RESULT_IS_FINAL(matches[i], is_or)) + continue; + + /* + * First check whether the constant is below the lower + * boundary (in that case we can skip the bucket, because + * there's no overlap). + * + * We don't store collations used to build the statistics, + * but we can use the collation for the attribute itself, + * as stored in varcollid. We do reset the statistics after + * a type change (including collation change), so this is + * OK. We may need to relax this after allowing extended + * statistics on expressions. + */ + match = DatumGetBool(FunctionCall2Coll(&opproc, + var->varcollid, + item->values[idx], + item->values[idx2])); + + /* update the match bitmap with the result */ + matches[i] = RESULT_MERGE(matches[i], is_or, match); + } + } } else if (IsA(clause, ScalarArrayOpExpr)) { @@ -1665,7 +1731,7 @@ mcv_get_match_bitmap(PlannerInfo *root, List *clauses, fmgr_info(get_opcode(expr->opno), &opproc); /* extract the var and const from the expression */ - if (examine_clause_args(expr->args, &var, &cst, &varonleft)) + if (examine_clause_args(expr->args, &var, NULL, &cst, &varonleft)) { int idx; @@ -1679,6 +1745,7 @@ mcv_get_match_bitmap(PlannerInfo *root, List *clauses, /* ScalarArrayOpExpr has the Var always on the left */ Assert(varonleft); + Assert(cst); if (!cst->constisnull) { diff --git a/src/include/statistics/extended_stats_internal.h b/src/include/statistics/extended_stats_internal.h index 6c039a81c2..ee34a897c8 100644 --- a/src/include/statistics/extended_stats_internal.h +++ b/src/include/statistics/extended_stats_internal.h @@ -96,7 +96,7 @@ extern SortItem *build_sorted_items(int numrows, int *nitems, HeapTuple *rows, TupleDesc tdesc, MultiSortSupport mss, int numattrs, AttrNumber *attnums); -extern bool examine_clause_args(List *args, Var **varp, +extern bool examine_clause_args(List *args, Var **var1p, Var **var2p, Const **cstp, bool *varonleftp); extern Selectivity mcv_clauselist_selectivity(PlannerInfo *root, diff --git a/src/test/regress/expected/stats_ext.out b/src/test/regress/expected/stats_ext.out index 3aba4a37c6..481be40141 100644 --- a/src/test/regress/expected/stats_ext.out +++ b/src/test/regress/expected/stats_ext.out @@ -940,6 +940,18 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a = 1 OR b = ' 343 | 200 (1 row) +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a > c'); + estimated | actual +-----------+-------- + 1667 | 3750 +(1 row) + +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a < c'); + estimated | actual +-----------+-------- + 1667 | 0 +(1 row) + SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a IN (1, 2, 51, 52) AND b IN ( ''1'', ''2'')'); estimated | actual -----------+-------- @@ -1081,6 +1093,18 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a = 1 OR b = ' 200 | 200 (1 row) +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a > c'); + estimated | actual +-----------+-------- + 3750 | 3750 +(1 row) + +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a < c'); + estimated | actual +-----------+-------- + 1 | 0 +(1 row) + SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a IN (1, 2, 51, 52) AND b IN ( ''1'', ''2'')'); estimated | actual -----------+-------- @@ -1284,6 +1308,12 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a IS NULL AND 3750 | 2500 (1 row) +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE b = d'); + estimated | actual +-----------+-------- + 25 | 2500 +(1 row) + -- create statistics CREATE STATISTICS mcv_lists_stats (mcv) ON a, b, d FROM mcv_lists; ANALYZE mcv_lists; @@ -1317,6 +1347,12 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a IS NULL AND 2500 | 2500 (1 row) +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE b = d'); + estimated | actual +-----------+-------- + 2500 | 2500 +(1 row) + -- mcv with pass-by-ref fixlen types, e.g. uuid CREATE TABLE mcv_lists_uuid ( a UUID, @@ -1408,6 +1444,18 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a AND 1094 | 0 (1 row) +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a = b'); + estimated | actual +-----------+-------- + 9950 | 2500 +(1 row) + +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a = b AND b = c'); + estimated | actual +-----------+-------- + 50 | 2500 +(1 row) + CREATE STATISTICS mcv_lists_bool_stats (mcv) ON a, b, c FROM mcv_lists_bool; ANALYZE mcv_lists_bool; @@ -1435,6 +1483,18 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a AND 1 | 0 (1 row) +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a = b'); + estimated | actual +-----------+-------- + 2500 | 2500 +(1 row) + +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a = b AND b = c'); + estimated | actual +-----------+-------- + 2500 | 2500 +(1 row) + -- check the ability to use multiple MCV lists CREATE TABLE mcv_lists_multi ( a INTEGER, @@ -1493,6 +1553,12 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = 0 OR 2649 | 1572 (1 row) +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = b AND c = d'); + estimated | actual +-----------+-------- + 1 | 5000 +(1 row) + -- create separate MCV statistics CREATE STATISTICS mcv_lists_multi_1 (mcv) ON a, b FROM mcv_lists_multi; CREATE STATISTICS mcv_lists_multi_2 (mcv) ON c, d FROM mcv_lists_multi; @@ -1539,6 +1605,12 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = 0 OR 1571 | 1572 (1 row) +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = b AND c = d'); + estimated | actual +-----------+-------- + 5000 | 5000 +(1 row) + DROP TABLE mcv_lists_multi; -- Permission tests. Users should not be able to see specific data values in -- the extended statistics, if they lack permission to see those values in diff --git a/src/test/regress/sql/stats_ext.sql b/src/test/regress/sql/stats_ext.sql index 54ceb1f4ee..f5e4468129 100644 --- a/src/test/regress/sql/stats_ext.sql +++ b/src/test/regress/sql/stats_ext.sql @@ -498,6 +498,10 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a = 1 OR b = ' SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a = 1 OR b = ''1'' OR c = 1 OR d IS NOT NULL'); +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a > c'); + +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a < c'); + SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a IN (1, 2, 51, 52) AND b IN ( ''1'', ''2'')'); SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a IN (1, 2, 51, 52, NULL) AND b IN ( ''1'', ''2'', NULL)'); @@ -549,6 +553,10 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a = 1 OR b = ' SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a = 1 OR b = ''1'' OR c = 1 OR d IS NOT NULL'); +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a > c'); + +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a < c'); + SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a IN (1, 2, 51, 52) AND b IN ( ''1'', ''2'')'); SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a IN (1, 2, 51, 52, NULL) AND b IN ( ''1'', ''2'', NULL)'); @@ -656,6 +664,8 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a = 1 OR b = ' SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a IS NULL AND (b = ''x'' OR d = ''x'')'); +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE b = d'); + -- create statistics CREATE STATISTICS mcv_lists_stats (mcv) ON a, b, d FROM mcv_lists; @@ -674,6 +684,8 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a = 1 OR b = ' SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE a IS NULL AND (b = ''x'' OR d = ''x'')'); +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists WHERE b = d'); + -- mcv with pass-by-ref fixlen types, e.g. uuid CREATE TABLE mcv_lists_uuid ( a UUID, @@ -746,6 +758,10 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a AND SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a AND b AND NOT c'); +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a = b'); + +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a = b AND b = c'); + CREATE STATISTICS mcv_lists_bool_stats (mcv) ON a, b, c FROM mcv_lists_bool; @@ -759,6 +775,10 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a AND SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a AND b AND NOT c'); +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a = b'); + +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_bool WHERE NOT a = b AND b = c'); + -- check the ability to use multiple MCV lists CREATE TABLE mcv_lists_multi ( a INTEGER, @@ -785,6 +805,7 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE b = 0 OR SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = 0 AND b = 0 AND c = 0 AND d = 0'); SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE (a = 0 AND b = 0) OR (c = 0 AND d = 0)'); SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = 0 OR b = 0 OR c = 0 OR d = 0'); +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = b AND c = d'); -- create separate MCV statistics CREATE STATISTICS mcv_lists_multi_1 (mcv) ON a, b FROM mcv_lists_multi; @@ -799,6 +820,7 @@ SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE b = 0 OR SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = 0 AND b = 0 AND c = 0 AND d = 0'); SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE (a = 0 AND b = 0) OR (c = 0 AND d = 0)'); SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = 0 OR b = 0 OR c = 0 OR d = 0'); +SELECT * FROM check_estimated_rows('SELECT * FROM mcv_lists_multi WHERE a = b AND c = d'); DROP TABLE mcv_lists_multi; -- 2.21.1 --qmgrvggedyprimol-- ^ permalink raw reply [nested|flat] 6+ messages in thread
* [PATCH v3] Change wal_compression=on to the first of zstd, lz4, pglz @ 2026-07-31 12:24 Christoph Berg <myon@debian.org> 0 siblings, 0 replies; 6+ messages in thread From: Christoph Berg @ 2026-07-31 12:24 UTC (permalink / raw) Previously, wal_compression=on was an alias for pglz, with the idea that users could make an informed choice to pick a better option. But in practice, users either don't want to make that choice (they just want WAL compression), can't really pick the best option (they are setting the default in an environment where someone else is running the workload), or simply don't know that there are other options (previously, "on" was the only choice available). In all these cases, mapping "on" to something that isn't pglz is better. It is strictly slower and does not compress better. We pick zstd here. Users can still make the informed choice and switch to lz4 if their workload works better there, but zstd is still better than pglz in that case. Like for the default TOAST compression, the actual default "on" value depends on if PostgreSQL was compiled with the compression algorithms. The first of zstd, lz4, pglz is picked. (Only the latter is always available, but practically, builds will have at least one of the better algorithms.) --- doc/src/sgml/config.sgml | 12 ++++++------ src/backend/utils/misc/guc_tables.c | 8 ++++---- src/backend/utils/misc/postgresql.conf.sample | 3 ++- src/include/access/xlog.h | 13 +++++++++++++ 4 files changed, 25 insertions(+), 11 deletions(-) diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml index aa7b1bd75d2..9bfe0443848 100644 --- a/doc/src/sgml/config.sgml +++ b/doc/src/sgml/config.sgml @@ -3667,12 +3667,12 @@ include_dir 'conf.d' <xref linkend="guc-full-page-writes"/> is on, during a base backup, etc.). A compressed page image will be decompressed during WAL replay. - The supported methods are <literal>pglz</literal>, - <literal>lz4</literal> (if <productname>PostgreSQL</productname> - was compiled with <option>--with-lz4</option>) and - <literal>zstd</literal> (if <productname>PostgreSQL</productname> - was compiled with <option>--with-zstd</option>). - The value <literal>on</literal> is a historical spelling of <literal>pglz</literal>. + The supported methods are <literal>off</literal>, <literal>on</literal>, + <literal>zstd</literal> (if <productname>PostgreSQL</productname> was compiled with <option>--with-zstd</option>) + <literal>lz4</literal> (if <productname>PostgreSQL</productname> was compiled with <option>--with-lz4</option>), and + <literal>pglz</literal>. + The value <literal>on</literal> selects the first of <literal>zstd</literal>, + <literal>lz4</literal>, <literal>pglz</literal> that is available. The default value is <literal>off</literal>. Only superusers and users with the appropriate <literal>SET</literal> privilege can change this setting. diff --git a/src/backend/utils/misc/guc_tables.c b/src/backend/utils/misc/guc_tables.c index 1ec460b6a82..e0b21053287 100644 --- a/src/backend/utils/misc/guc_tables.c +++ b/src/backend/utils/misc/guc_tables.c @@ -484,13 +484,13 @@ static const struct config_enum_entry wal_compression_options[] = { #ifdef USE_ZSTD {"zstd", WAL_COMPRESSION_ZSTD, false}, #endif - {"on", WAL_COMPRESSION_PGLZ, false}, + {"on", DEFAULT_WAL_COMPRESSION, false}, {"off", WAL_COMPRESSION_NONE, false}, - {"true", WAL_COMPRESSION_PGLZ, true}, + {"true", DEFAULT_WAL_COMPRESSION, true}, {"false", WAL_COMPRESSION_NONE, true}, - {"yes", WAL_COMPRESSION_PGLZ, true}, + {"yes", DEFAULT_WAL_COMPRESSION, true}, {"no", WAL_COMPRESSION_NONE, true}, - {"1", WAL_COMPRESSION_PGLZ, true}, + {"1", DEFAULT_WAL_COMPRESSION, true}, {"0", WAL_COMPRESSION_NONE, true}, {NULL, 0, false} }; diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample index 7958653077b..9d178fb09c1 100644 --- a/src/backend/utils/misc/postgresql.conf.sample +++ b/src/backend/utils/misc/postgresql.conf.sample @@ -262,7 +262,8 @@ #wal_log_hints = off # also do full page writes of non-critical updates # (change requires restart) #wal_compression = off # enables compression of full-page writes; - # off, pglz (or "on"), lz4, or zstd + # off, on, zstd, lz4, or pglz (on = zstd if + # available, else lz4 if available, else pglz) #wal_init_zero = on # zero-fill new WAL files #wal_recycle = on # recycle WAL files #wal_buffers = -1 # min 32kB, -1 sets based on shared_buffers diff --git a/src/include/access/xlog.h b/src/include/access/xlog.h index 4dd98624204..9259b3461c7 100644 --- a/src/include/access/xlog.h +++ b/src/include/access/xlog.h @@ -87,6 +87,19 @@ typedef enum WalCompression WAL_COMPRESSION_ZSTD, } WalCompression; +/* + * Choose an appropriate default WAL compression method for wal_compression=on. + * Prefer zstd when compiled in; otherwise use lz4 if available, falling back + * to pglz. + */ +#ifdef USE_ZSTD +#define DEFAULT_WAL_COMPRESSION WAL_COMPRESSION_ZSTD +#elif defined(USE_LZ4) +#define DEFAULT_WAL_COMPRESSION WAL_COMPRESSION_LZ4 +#else +#define DEFAULT_WAL_COMPRESSION WAL_COMPRESSION_PGLZ +#endif + /* Recovery states */ typedef enum RecoveryState { -- 2.53.0 --CjtMoaqLlMP6LcXJ-- ^ permalink raw reply [nested|flat] 6+ messages in thread
end of thread, other threads:[~2026-07-31 12:24 UTC | newest] Thread overview: 6+ messages (download: mbox mbox.gz follow: Atom feed) -- links below jump to the message on this page -- 2019-11-11 00:34 [PATCH 2/3] Support clauses of the form Var op Var Tomas Vondra <tv@fuzzy.cz> 2019-11-11 00:34 [PATCH 2/3] Support clauses of the form Var op Var Tomas Vondra <tv@fuzzy.cz> 2019-11-11 00:34 [PATCH 2/3] Support clauses of the form Var op Var Tomas Vondra <tv@fuzzy.cz> 2020-03-08 22:27 [PATCH 4/4] Support clauses of the form Var op Var Tomas Vondra <tv@fuzzy.cz> 2020-03-17 01:57 [PATCH 2/2] Support clauses of the form Var op Var Tomas Vondra <tv@fuzzy.cz> 2026-07-31 12:24 [PATCH v3] Change wal_compression=on to the first of zstd, lz4, pglz Christoph Berg <myon@debian.org>
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