diff options
| -rw-r--r-- | src/backend/optimizer/plan/planner.c | 7 | ||||
| -rw-r--r-- | src/test/regress/expected/aggregates.out | 24 | ||||
| -rw-r--r-- | src/test/regress/sql/aggregates.sql | 10 |
3 files changed, 39 insertions, 2 deletions
diff --git a/src/backend/optimizer/plan/planner.c b/src/backend/optimizer/plan/planner.c index 078df86b5ea..cbf55c51a22 100644 --- a/src/backend/optimizer/plan/planner.c +++ b/src/backend/optimizer/plan/planner.c @@ -2643,6 +2643,13 @@ remove_useless_groupby_columns(PlannerInfo *root) if (rte->rtekind != RTE_RELATION) continue; + /* + * We must skip inheritance parent tables as some of the child rels + * may cause duplicate rows. + */ + if (rte->inh) + continue; + /* Nothing to do unless this rel has multiple Vars in GROUP BY */ relattnos = groupbyattnos[relid]; if (bms_membership(relattnos) != BMS_MULTIPLE) diff --git a/src/test/regress/expected/aggregates.out b/src/test/regress/expected/aggregates.out index a1663f08c22..ec13dc02d01 100644 --- a/src/test/regress/expected/aggregates.out +++ b/src/test/regress/expected/aggregates.out @@ -1014,7 +1014,29 @@ explain (costs off) select * from t3 group by a,b,c; -> Seq Scan on t3 (3 rows) -drop table t1; +create temp table t1c () inherits (t1); +-- Ensure we don't remove any columns when t1 has a child table +explain (costs off) select * from t1 group by a,b,c,d; + QUERY PLAN +------------------------------------- + HashAggregate + Group Key: t1.a, t1.b, t1.c, t1.d + -> Append + -> Seq Scan on t1 + -> Seq Scan on t1c +(5 rows) + +-- Okay to remove columns if we're only querying the parent. +explain (costs off) select * from only t1 group by a,b,c,d; + QUERY PLAN +---------------------- + HashAggregate + Group Key: a, b + -> Seq Scan on t1 +(3 rows) + +drop table t1 cascade; +NOTICE: drop cascades to table t1c drop table t2; drop table t3; -- diff --git a/src/test/regress/sql/aggregates.sql b/src/test/regress/sql/aggregates.sql index 7e129f74bc2..bcf719f28ff 100644 --- a/src/test/regress/sql/aggregates.sql +++ b/src/test/regress/sql/aggregates.sql @@ -362,7 +362,15 @@ group by t1.a,t1.b,t1.c,t1.d,t2.x,t2.z; -- Cannot optimize when PK is deferrable explain (costs off) select * from t3 group by a,b,c; -drop table t1; +create temp table t1c () inherits (t1); + +-- Ensure we don't remove any columns when t1 has a child table +explain (costs off) select * from t1 group by a,b,c,d; + +-- Okay to remove columns if we're only querying the parent. +explain (costs off) select * from only t1 group by a,b,c,d; + +drop table t1 cascade; drop table t2; drop table t3; |