diff --git a/src/backend/optimizer/plan/planner.c b/src/backend/optimizer/plan/planner.c index 3d33d46..c18c92d 100644 --- a/src/backend/optimizer/plan/planner.c +++ b/src/backend/optimizer/plan/planner.c @@ -996,10 +996,20 @@ inheritance_planner(PlannerInfo *root) RelOptInfo *final_rel; ListCell *lc; Index rti; + RangeTblEntry *parent_rte; Assert(parse->commandType != CMD_INSERT); /* + * If the parent RTE is a partitioned table, we should use that as the + * nominal relation, because we do not have the duplicate parent RTE, + * unlike in the case of a non-partitioned inheritance parent. + */ + parent_rte = rt_fetch(parentRTindex, root->parse->rtable); + if (parent_rte->relkind == RELKIND_PARTITIONED_TABLE) + nominalRelation = parentRTindex; + + /* * We generate a modified instance of the original Query for each target * relation, plan that, and put all the plans into a list that will be * controlled by a single ModifyTable node. All the instances share the @@ -1214,6 +1224,11 @@ inheritance_planner(PlannerInfo *root) * will not be otherwise referenced in the plan, doing so would give * rise to confusing use of multiple aliases in EXPLAIN output for * what the user will think is the "same" table.) + * + * If the parent is a partitioned table, we do not have a separate RTE + * representing it as a member of the inheritance set, because we do + * not create a scan plan for it. As mentioned at the top of this + * function, we make the parent RTE itself the nominal relation. */ if (nominalRelation < 0) nominalRelation = appinfo->child_relid; diff --git a/src/backend/optimizer/prep/prepunion.c b/src/backend/optimizer/prep/prepunion.c index 06e843d..10f7494 100644 --- a/src/backend/optimizer/prep/prepunion.c +++ b/src/backend/optimizer/prep/prepunion.c @@ -1374,9 +1374,17 @@ expand_inherited_rtentry(PlannerInfo *root, RangeTblEntry *rte, Index rti) Assert(rte->rtekind == RTE_SUBQUERY); return; } - /* Fast path for common case of childless table */ + /* + * Fast path for common case of childless table. However, a partitioned + * table RTE should *always* be processed by the later code as an + * inheritance set, possibly an empty one in the absence of any leaf + * partitions. It is wrong for the later phases to try to create a scan + * plan for a partitioned table, which would be the case if we turn off + * the inh flag here. + */ parentOID = rte->relid; - if (!has_subclass(parentOID)) + if (rte->relkind != RELKIND_PARTITIONED_TABLE && + !has_subclass(parentOID)) { /* Clear flag before returning */ rte->inh = false; @@ -1410,9 +1418,11 @@ expand_inherited_rtentry(PlannerInfo *root, RangeTblEntry *rte, Index rti) /* * Check that there's at least one descendant, else treat as no-child * case. This could happen despite above has_subclass() check, if table - * once had a child but no longer does. + * once had a child but no longer does. Again, do not disable inheritance + * for a partitioned table as described above. */ - if (list_length(inhOIDs) < 2) + if (rte->relkind != RELKIND_PARTITIONED_TABLE && + list_length(inhOIDs) < 2) { /* Clear flag before returning */ rte->inh = false; @@ -1450,6 +1460,18 @@ expand_inherited_rtentry(PlannerInfo *root, RangeTblEntry *rte, Index rti) newrelation = oldrelation; /* + * Ignore partitioned tables here, because we do not want them to + * be considered as child tables in the inheritance set. No scan + * plans will be created for them. + */ + if (newrelation->rd_rel->relkind == RELKIND_PARTITIONED_TABLE) + { + if (newrelation != oldrelation) + heap_close(newrelation, lockmode); + continue; + } + + /* * It is possible that the parent table has children that are temp * tables of other backends. We cannot safely access such tables * (because of buffering issues), and the best thing to do seems to be @@ -1548,9 +1570,11 @@ expand_inherited_rtentry(PlannerInfo *root, RangeTblEntry *rte, Index rti) * If all the children were temp tables, pretend it's a non-inheritance * situation. The duplicate RTE we added for the parent table is * harmless, so we don't bother to get rid of it; ditto for the useless - * PlanRowMark node. + * PlanRowMark node. Do not disable inheritance for partitioned tables + * as described above. */ - if (list_length(appinfos) < 2) + if (rte->relkind != RELKIND_PARTITIONED_TABLE && + list_length(appinfos) < 2) { /* Clear flag before returning */ rte->inh = false; diff --git a/src/test/regress/expected/inherit.out b/src/test/regress/expected/inherit.out index a8c8b28..7215f03 100644 --- a/src/test/regress/expected/inherit.out +++ b/src/test/regress/expected/inherit.out @@ -1598,6 +1598,14 @@ reset enable_bitmapscan; create table list_parted ( a varchar ) partition by list (a); +-- test scanning partitioned table without any partitions +explain (costs off) select * from list_parted; + QUERY PLAN +-------------------------- + Result + One-Time Filter: false +(2 rows) + create table part_ab_cd partition of list_parted for values in ('ab', 'cd'); create table part_ef_gh partition of list_parted for values in ('ef', 'gh'); create table part_null_xy partition of list_parted for values in (null, 'xy'); @@ -1605,77 +1613,74 @@ explain (costs off) select * from list_parted; QUERY PLAN -------------------------------- Append - -> Seq Scan on list_parted -> Seq Scan on part_ab_cd -> Seq Scan on part_ef_gh -> Seq Scan on part_null_xy -(5 rows) +(4 rows) explain (costs off) select * from list_parted where a is null; QUERY PLAN -------------------------------- Append - -> Seq Scan on list_parted - Filter: (a IS NULL) -> Seq Scan on part_null_xy Filter: (a IS NULL) -(5 rows) +(3 rows) explain (costs off) select * from list_parted where a is not null; QUERY PLAN --------------------------------- Append - -> Seq Scan on list_parted - Filter: (a IS NOT NULL) -> Seq Scan on part_ab_cd Filter: (a IS NOT NULL) -> Seq Scan on part_ef_gh Filter: (a IS NOT NULL) -> Seq Scan on part_null_xy Filter: (a IS NOT NULL) -(9 rows) +(7 rows) explain (costs off) select * from list_parted where a in ('ab', 'cd', 'ef'); QUERY PLAN ---------------------------------------------------------- Append - -> Seq Scan on list_parted - Filter: ((a)::text = ANY ('{ab,cd,ef}'::text[])) -> Seq Scan on part_ab_cd Filter: ((a)::text = ANY ('{ab,cd,ef}'::text[])) -> Seq Scan on part_ef_gh Filter: ((a)::text = ANY ('{ab,cd,ef}'::text[])) -(7 rows) +(5 rows) explain (costs off) select * from list_parted where a = 'ab' or a in (null, 'cd'); QUERY PLAN --------------------------------------------------------------------------------------- Append - -> Seq Scan on list_parted - Filter: (((a)::text = 'ab'::text) OR ((a)::text = ANY ('{NULL,cd}'::text[]))) -> Seq Scan on part_ab_cd Filter: (((a)::text = 'ab'::text) OR ((a)::text = ANY ('{NULL,cd}'::text[]))) -> Seq Scan on part_ef_gh Filter: (((a)::text = 'ab'::text) OR ((a)::text = ANY ('{NULL,cd}'::text[]))) -> Seq Scan on part_null_xy Filter: (((a)::text = 'ab'::text) OR ((a)::text = ANY ('{NULL,cd}'::text[]))) -(9 rows) +(7 rows) explain (costs off) select * from list_parted where a = 'ab'; QUERY PLAN ------------------------------------------ Append - -> Seq Scan on list_parted - Filter: ((a)::text = 'ab'::text) -> Seq Scan on part_ab_cd Filter: ((a)::text = 'ab'::text) -(5 rows) +(3 rows) create table range_list_parted ( a int, b char(2) ) partition by range (a); create table part_1_10 partition of range_list_parted for values from (1) to (10) partition by list (b); +-- test scanning partitioned table without any partitions +explain (costs off) select * from range_list_parted; + QUERY PLAN +-------------------------- + Result + One-Time Filter: false +(2 rows) + create table part_1_10_ab partition of part_1_10 for values in ('ab'); create table part_1_10_cd partition of part_1_10 for values in ('cd'); create table part_10_20 partition of range_list_parted for values from (10) to (20) partition by list (b); @@ -1689,14 +1694,9 @@ create table part_40_inf_ab partition of part_40_inf for values in ('ab'); create table part_40_inf_cd partition of part_40_inf for values in ('cd'); create table part_40_inf_null partition of part_40_inf for values in (null); explain (costs off) select * from range_list_parted; - QUERY PLAN -------------------------------------- + QUERY PLAN +------------------------------------ Append - -> Seq Scan on range_list_parted - -> Seq Scan on part_1_10 - -> Seq Scan on part_10_20 - -> Seq Scan on part_21_30 - -> Seq Scan on part_40_inf -> Seq Scan on part_1_10_ab -> Seq Scan on part_1_10_cd -> Seq Scan on part_10_20_ab @@ -1706,36 +1706,22 @@ explain (costs off) select * from range_list_parted; -> Seq Scan on part_40_inf_ab -> Seq Scan on part_40_inf_cd -> Seq Scan on part_40_inf_null -(15 rows) +(10 rows) explain (costs off) select * from range_list_parted where a = 5; - QUERY PLAN -------------------------------------- + QUERY PLAN +-------------------------------- Append - -> Seq Scan on range_list_parted - Filter: (a = 5) - -> Seq Scan on part_1_10 - Filter: (a = 5) -> Seq Scan on part_1_10_ab Filter: (a = 5) -> Seq Scan on part_1_10_cd Filter: (a = 5) -(9 rows) +(5 rows) explain (costs off) select * from range_list_parted where b = 'ab'; - QUERY PLAN -------------------------------------- + QUERY PLAN +------------------------------------ Append - -> Seq Scan on range_list_parted - Filter: (b = 'ab'::bpchar) - -> Seq Scan on part_1_10 - Filter: (b = 'ab'::bpchar) - -> Seq Scan on part_10_20 - Filter: (b = 'ab'::bpchar) - -> Seq Scan on part_21_30 - Filter: (b = 'ab'::bpchar) - -> Seq Scan on part_40_inf - Filter: (b = 'ab'::bpchar) -> Seq Scan on part_1_10_ab Filter: (b = 'ab'::bpchar) -> Seq Scan on part_10_20_ab @@ -1744,27 +1730,19 @@ explain (costs off) select * from range_list_parted where b = 'ab'; Filter: (b = 'ab'::bpchar) -> Seq Scan on part_40_inf_ab Filter: (b = 'ab'::bpchar) -(19 rows) +(9 rows) explain (costs off) select * from range_list_parted where a between 3 and 23 and b in ('ab'); QUERY PLAN ----------------------------------------------------------------- Append - -> Seq Scan on range_list_parted - Filter: ((a >= 3) AND (a <= 23) AND (b = 'ab'::bpchar)) - -> Seq Scan on part_1_10 - Filter: ((a >= 3) AND (a <= 23) AND (b = 'ab'::bpchar)) - -> Seq Scan on part_10_20 - Filter: ((a >= 3) AND (a <= 23) AND (b = 'ab'::bpchar)) - -> Seq Scan on part_21_30 - Filter: ((a >= 3) AND (a <= 23) AND (b = 'ab'::bpchar)) -> Seq Scan on part_1_10_ab Filter: ((a >= 3) AND (a <= 23) AND (b = 'ab'::bpchar)) -> Seq Scan on part_10_20_ab Filter: ((a >= 3) AND (a <= 23) AND (b = 'ab'::bpchar)) -> Seq Scan on part_21_30_ab Filter: ((a >= 3) AND (a <= 23) AND (b = 'ab'::bpchar)) -(15 rows) +(7 rows) /* Should select no rows because range partition key cannot be null */ explain (costs off) select * from range_list_parted where a is null; @@ -1776,37 +1754,17 @@ explain (costs off) select * from range_list_parted where a is null; /* Should only select rows from the null-accepting partition */ explain (costs off) select * from range_list_parted where b is null; - QUERY PLAN -------------------------------------- + QUERY PLAN +------------------------------------ Append - -> Seq Scan on range_list_parted - Filter: (b IS NULL) - -> Seq Scan on part_1_10 - Filter: (b IS NULL) - -> Seq Scan on part_10_20 - Filter: (b IS NULL) - -> Seq Scan on part_21_30 - Filter: (b IS NULL) - -> Seq Scan on part_40_inf - Filter: (b IS NULL) -> Seq Scan on part_40_inf_null Filter: (b IS NULL) -(13 rows) +(3 rows) explain (costs off) select * from range_list_parted where a is not null and a < 67; QUERY PLAN ------------------------------------------------ Append - -> Seq Scan on range_list_parted - Filter: ((a IS NOT NULL) AND (a < 67)) - -> Seq Scan on part_1_10 - Filter: ((a IS NOT NULL) AND (a < 67)) - -> Seq Scan on part_10_20 - Filter: ((a IS NOT NULL) AND (a < 67)) - -> Seq Scan on part_21_30 - Filter: ((a IS NOT NULL) AND (a < 67)) - -> Seq Scan on part_40_inf - Filter: ((a IS NOT NULL) AND (a < 67)) -> Seq Scan on part_1_10_ab Filter: ((a IS NOT NULL) AND (a < 67)) -> Seq Scan on part_1_10_cd @@ -1825,23 +1783,19 @@ explain (costs off) select * from range_list_parted where a is not null and a < Filter: ((a IS NOT NULL) AND (a < 67)) -> Seq Scan on part_40_inf_null Filter: ((a IS NOT NULL) AND (a < 67)) -(29 rows) +(19 rows) explain (costs off) select * from range_list_parted where a >= 30; - QUERY PLAN -------------------------------------- + QUERY PLAN +------------------------------------ Append - -> Seq Scan on range_list_parted - Filter: (a >= 30) - -> Seq Scan on part_40_inf - Filter: (a >= 30) -> Seq Scan on part_40_inf_ab Filter: (a >= 30) -> Seq Scan on part_40_inf_cd Filter: (a >= 30) -> Seq Scan on part_40_inf_null Filter: (a >= 30) -(11 rows) +(7 rows) drop table list_parted cascade; NOTICE: drop cascades to 3 other objects diff --git a/src/test/regress/sql/inherit.sql b/src/test/regress/sql/inherit.sql index a8b7eb1..fa0bb47 100644 --- a/src/test/regress/sql/inherit.sql +++ b/src/test/regress/sql/inherit.sql @@ -570,6 +570,10 @@ reset enable_bitmapscan; create table list_parted ( a varchar ) partition by list (a); + +-- test scanning partitioned table without any partitions +explain (costs off) select * from list_parted; + create table part_ab_cd partition of list_parted for values in ('ab', 'cd'); create table part_ef_gh partition of list_parted for values in ('ef', 'gh'); create table part_null_xy partition of list_parted for values in (null, 'xy'); @@ -586,6 +590,10 @@ create table range_list_parted ( b char(2) ) partition by range (a); create table part_1_10 partition of range_list_parted for values from (1) to (10) partition by list (b); + +-- test scanning partitioned table without any partitions +explain (costs off) select * from range_list_parted; + create table part_1_10_ab partition of part_1_10 for values in ('ab'); create table part_1_10_cd partition of part_1_10 for values in ('cd'); create table part_10_20 partition of range_list_parted for values from (10) to (20) partition by list (b);