diff options
Diffstat (limited to 'src/test')
| -rw-r--r-- | src/test/regress/expected/union.out | 86 | ||||
| -rw-r--r-- | src/test/regress/sql/union.sql | 38 |
2 files changed, 122 insertions, 2 deletions
diff --git a/src/test/regress/expected/union.out b/src/test/regress/expected/union.out index 15931beea3a..fb77d108337 100644 --- a/src/test/regress/expected/union.out +++ b/src/test/regress/expected/union.out @@ -1217,7 +1217,7 @@ select event_id drop table events_child, events, other_events; reset enable_indexonlyscan; -- --- Test handling of UNION with provably empty inputs +-- Test handling of UNION / EXCEPT / INTERSECT with provably empty inputs -- -- Ensure the empty UNION input is pruned and de-duplication is done for the -- remaining relation. @@ -1271,6 +1271,90 @@ ORDER BY 1; One-Time Filter: false (7 rows) +-- Ensure the planner provides a const-false Result node +EXPLAIN (COSTS OFF, VERBOSE) +SELECT two FROM tenk1 WHERE 1=2 +INTERSECT +SELECT four FROM tenk1 +ORDER BY 1; + QUERY PLAN +--------------------------------------------------------------------- + Sort + Output: unnamed_subquery.two + Sort Key: unnamed_subquery.two + -> Result + Output: unnamed_subquery.two + Replaces: Aggregate on unnamed_subquery, unnamed_subquery_1 + One-Time Filter: false +(7 rows) + +-- As above, with the inputs swapped +EXPLAIN (COSTS OFF, VERBOSE) +SELECT four FROM tenk1 +INTERSECT +SELECT two FROM tenk1 WHERE 1=2 +ORDER BY 1; + QUERY PLAN +--------------------------------------------------------------------- + Sort + Output: unnamed_subquery.four + Sort Key: unnamed_subquery.four + -> Result + Output: unnamed_subquery.four + Replaces: Aggregate on unnamed_subquery, unnamed_subquery_1 + One-Time Filter: false +(7 rows) + +-- Try with both inputs dummy +EXPLAIN (COSTS OFF, VERBOSE) +SELECT four FROM tenk1 WHERE 1=2 +INTERSECT +SELECT two FROM tenk1 WHERE 1=2 +ORDER BY 1; + QUERY PLAN +--------------------------------------------------------------------- + Sort + Output: unnamed_subquery.four + Sort Key: unnamed_subquery.four + -> Result + Output: unnamed_subquery.four + Replaces: Aggregate on unnamed_subquery, unnamed_subquery_1 + One-Time Filter: false +(7 rows) + +-- Ensure the planner provides a const-false Result node when the left input +-- is empty +EXPLAIN (COSTS OFF, VERBOSE) +SELECT two FROM tenk1 WHERE 1=2 +EXCEPT +SELECT four FROM tenk1 +ORDER BY 1; + QUERY PLAN +--------------------------------------------------------------------- + Sort + Output: unnamed_subquery.two + Sort Key: unnamed_subquery.two + -> Result + Output: unnamed_subquery.two + Replaces: Aggregate on unnamed_subquery, unnamed_subquery_1 + One-Time Filter: false +(7 rows) + +-- Ensure the planner only scans the left input when right input is empty +EXPLAIN (COSTS OFF, VERBOSE) +SELECT two FROM tenk1 +EXCEPT ALL +SELECT four FROM tenk1 WHERE 1=2 +ORDER BY 1; + QUERY PLAN +-------------------------------- + Sort + Output: tenk1.two + Sort Key: tenk1.two + -> Seq Scan on public.tenk1 + Output: tenk1.two +(5 rows) + -- Test constraint exclusion of UNION ALL subqueries explain (costs off) SELECT * FROM diff --git a/src/test/regress/sql/union.sql b/src/test/regress/sql/union.sql index e252316f69b..782cca23701 100644 --- a/src/test/regress/sql/union.sql +++ b/src/test/regress/sql/union.sql @@ -460,7 +460,7 @@ drop table events_child, events, other_events; reset enable_indexonlyscan; -- --- Test handling of UNION with provably empty inputs +-- Test handling of UNION / EXCEPT / INTERSECT with provably empty inputs -- -- Ensure the empty UNION input is pruned and de-duplication is done for the @@ -487,6 +487,42 @@ UNION SELECT ten FROM tenk1 WHERE 1=2 ORDER BY 1; +-- Ensure the planner provides a const-false Result node +EXPLAIN (COSTS OFF, VERBOSE) +SELECT two FROM tenk1 WHERE 1=2 +INTERSECT +SELECT four FROM tenk1 +ORDER BY 1; + +-- As above, with the inputs swapped +EXPLAIN (COSTS OFF, VERBOSE) +SELECT four FROM tenk1 +INTERSECT +SELECT two FROM tenk1 WHERE 1=2 +ORDER BY 1; + +-- Try with both inputs dummy +EXPLAIN (COSTS OFF, VERBOSE) +SELECT four FROM tenk1 WHERE 1=2 +INTERSECT +SELECT two FROM tenk1 WHERE 1=2 +ORDER BY 1; + +-- Ensure the planner provides a const-false Result node when the left input +-- is empty +EXPLAIN (COSTS OFF, VERBOSE) +SELECT two FROM tenk1 WHERE 1=2 +EXCEPT +SELECT four FROM tenk1 +ORDER BY 1; + +-- Ensure the planner only scans the left input when right input is empty +EXPLAIN (COSTS OFF, VERBOSE) +SELECT two FROM tenk1 +EXCEPT ALL +SELECT four FROM tenk1 WHERE 1=2 +ORDER BY 1; + -- Test constraint exclusion of UNION ALL subqueries explain (costs off) SELECT * FROM |