Files
openGauss-server/src/test/regress/sql/union.sql
2021-09-23 15:19:37 +08:00

306 lines
7.1 KiB
SQL

--
-- UNION (also INTERSECT, EXCEPT)
--
-- Simple UNION constructs
SELECT 1 AS two UNION SELECT 2 ORDER BY 1;
SELECT 1 AS one UNION SELECT 1 ORDER BY 1;
SELECT 1 AS two UNION ALL SELECT 2 ORDER BY 1;
SELECT 1 AS two UNION ALL SELECT 1 ORDER BY 1;
SELECT 1 AS three UNION SELECT 2 UNION SELECT 3 ORDER BY 1;
SELECT 1 AS two UNION SELECT 2 UNION SELECT 2 ORDER BY 1;
SELECT 1 AS three UNION SELECT 2 UNION ALL SELECT 2 ORDER BY 1;
SELECT 1.1 AS two UNION SELECT 2.2 ORDER BY 1;
-- Mixed types
SELECT 1.1 AS two UNION SELECT 2 ORDER BY 1;
SELECT 1 AS two UNION SELECT 2.2 ORDER BY 1;
SELECT 1 AS one UNION SELECT 1.0::float8 ORDER BY 1;
SELECT 1.1 AS two UNION ALL SELECT 2 ORDER BY 1;
SELECT 1.0::float8 AS two UNION ALL SELECT 1 ORDER BY 1;
SELECT 1.1 AS three UNION SELECT 2 UNION SELECT 3 ORDER BY 1;
SELECT 1.1::float8 AS two UNION SELECT 2 UNION SELECT 2.0::float8 ORDER BY 1;
SELECT 1.1 AS three UNION SELECT 2 UNION ALL SELECT 2 ORDER BY 1;
SELECT 1.1 AS two UNION (SELECT 2 UNION ALL SELECT 2) ORDER BY 1;
--
-- Try testing from tables...
--
SELECT f1 AS five FROM FLOAT8_TBL
UNION
SELECT f1 FROM FLOAT8_TBL
ORDER BY 1;
SELECT f1 AS ten FROM FLOAT8_TBL
UNION ALL
SELECT f1 FROM FLOAT8_TBL
ORDER BY 1;
SELECT f1 AS nine FROM FLOAT8_TBL
UNION
SELECT f1 FROM INT4_TBL
ORDER BY 1;
SELECT f1 AS ten FROM FLOAT8_TBL
UNION ALL
SELECT f1 FROM INT4_TBL
ORDER BY 1;
SELECT f1 AS five FROM FLOAT8_TBL
WHERE f1 BETWEEN -1e6 AND 1e6
UNION
SELECT f1 FROM INT4_TBL
WHERE f1 BETWEEN 0 AND 1000000
ORDER BY 1;
SELECT CAST(f1 AS char(4)) AS three FROM VARCHAR_TBL
UNION
SELECT f1 FROM CHAR_TBL
ORDER BY 1;
SELECT f1 AS three FROM VARCHAR_TBL
UNION
SELECT CAST(f1 AS varchar) FROM CHAR_TBL
ORDER BY 1;
SELECT f1 AS eight FROM VARCHAR_TBL
UNION ALL
SELECT f1 FROM CHAR_TBL
ORDER BY 1;
SELECT f1 AS five FROM TEXT_TBL
UNION
SELECT f1 FROM VARCHAR_TBL
UNION
SELECT TRIM(TRAILING FROM f1) FROM CHAR_TBL
ORDER BY 1;
--
-- INTERSECT and EXCEPT
--
SELECT q2 FROM int8_tbl INTERSECT SELECT q1 FROM int8_tbl ORDER BY 1;
SELECT q2 FROM int8_tbl INTERSECT ALL SELECT q1 FROM int8_tbl ORDER BY 1;
SELECT q2 FROM int8_tbl EXCEPT SELECT q1 FROM int8_tbl ORDER BY 1;
SELECT q2 FROM int8_tbl EXCEPT ALL SELECT q1 FROM int8_tbl ORDER BY 1;
SELECT q2 FROM int8_tbl EXCEPT ALL SELECT DISTINCT q1 FROM int8_tbl ORDER BY 1;
SELECT q1 FROM int8_tbl EXCEPT SELECT q2 FROM int8_tbl ORDER BY 1;
SELECT q1 FROM int8_tbl EXCEPT ALL SELECT q2 FROM int8_tbl ORDER BY 1;
SELECT q1 FROM int8_tbl EXCEPT ALL SELECT DISTINCT q2 FROM int8_tbl ORDER BY 1;
--
-- Mixed types
--
SELECT f1 FROM float8_tbl INTERSECT SELECT f1 FROM int4_tbl ORDER BY 1;
SELECT f1 FROM float8_tbl EXCEPT SELECT f1 FROM int4_tbl ORDER BY 1;
--
-- Operator precedence and (((((extra))))) parentheses
--
SELECT q1 FROM int8_tbl INTERSECT SELECT q2 FROM int8_tbl UNION ALL SELECT q2 FROM int8_tbl ORDER BY 1;
SELECT q1 FROM int8_tbl INTERSECT (((SELECT q2 FROM int8_tbl UNION ALL SELECT q2 FROM int8_tbl))) ORDER BY 1;
(((SELECT q1 FROM int8_tbl INTERSECT SELECT q2 FROM int8_tbl))) UNION ALL SELECT q2 FROM int8_tbl ORDER BY 1;
SELECT q1 FROM int8_tbl UNION ALL SELECT q2 FROM int8_tbl EXCEPT SELECT q1 FROM int8_tbl ORDER BY 1;
SELECT q1 FROM int8_tbl UNION ALL (((SELECT q2 FROM int8_tbl EXCEPT SELECT q1 FROM int8_tbl ORDER BY 1))) ORDER BY 1;
(((SELECT q1 FROM int8_tbl UNION ALL SELECT q2 FROM int8_tbl))) EXCEPT SELECT q1 FROM int8_tbl ORDER BY 1;
--
-- Subqueries with ORDER BY & LIMIT clauses
--
-- In this syntax, ORDER BY/LIMIT apply to the result of the EXCEPT
SELECT q1,q2 FROM int8_tbl EXCEPT SELECT q2,q1 FROM int8_tbl
ORDER BY q2,q1;
-- This should fail, because q2 isn't a name of an EXCEPT output column
SELECT q1 FROM int8_tbl EXCEPT SELECT q2 FROM int8_tbl ORDER BY q2 LIMIT 1;
-- But this should work:
SELECT q1 FROM int8_tbl EXCEPT (((SELECT q2 FROM int8_tbl ORDER BY q2 LIMIT 1))) ORDER BY q1;
--
-- New syntaxes (7.1) permit new tests
--
(((((select * from int8_tbl ORDER BY q1, q2)))));
--
-- Check handling of a case with unknown constants. We don't guarantee
-- an undecorated constant will work in all cases, but historically this
-- usage has worked, so test we don't break it.
--
SELECT a.f1 FROM (SELECT 'test' AS f1 FROM varchar_tbl) a
UNION
SELECT b.f1 FROM (SELECT f1 FROM varchar_tbl) b
ORDER BY 1;
-- This should fail, but it should produce an error cursor
SELECT '3.4'::numeric UNION SELECT 'foo';
--
-- Test that expression-index constraints can be pushed down through
-- UNION or UNION ALL
--
-- Enforce use of COMMIT instead of 2PC for temporary objects
-- CREATE TEMP TABLE union_t1 (a text, b text);
CREATE TABLE union_t1 (a text, b text);
CREATE INDEX t1_ab_idx on union_t1 ((a || b));
-- CREATE TEMP TABLE union_t2 (ab text primary key);
CREATE TABLE union_t2 (ab text primary key);
INSERT INTO union_t1 VALUES ('a', 'b'), ('x', 'y');
INSERT INTO union_t2 VALUES ('ab'), ('xy');
set enable_seqscan = off;
set enable_indexscan = on;
set enable_bitmapscan = off;
explain (num_costs off)
SELECT * FROM
(SELECT a || b AS ab FROM union_t1
UNION ALL
SELECT * FROM union_t2) t
WHERE ab = 'ab';
explain (num_costs off)
SELECT * FROM
(SELECT a || b AS ab FROM union_t1
UNION
SELECT * FROM union_t2) t
WHERE ab = 'ab';
reset enable_seqscan;
reset enable_indexscan;
reset enable_bitmapscan;
DROP TABLE union_t1 CASCADE;
DROP TABLE union_t2 CASCADE;
-- doesn't pull down for intersect all query
create table reg_t1(r1 int, r2 regproc, r3 regproc);
insert into reg_t1 values(1, 'sin', 'cos'), (2, 'cos', 'tan'), (3, 'tan', 'cot');
explain (costs off, verbose on)
SELECT * FROM
(SELECT r2 FROM reg_t1
INTERSECT ALL
SELECT r3 FROM reg_t1) t;
SELECT * FROM
(SELECT r2 FROM reg_t1
INTERSECT ALL
SELECT r3 FROM reg_t1) t order by 1;
drop table reg_t1;
-- Test constraint exclusion of UNION ALL subqueries
explain (num_costs off)
SELECT * FROM
(SELECT 1 AS t, * FROM tenk1 a
UNION ALL
SELECT 2 AS t, * FROM tenk1 b) c
WHERE t = 2;
-- Test that we push quals into UNION sub-selects only when it's safe
explain (costs off)
SELECT * FROM
(SELECT 1 AS t, 2 AS x
UNION
SELECT 2 AS t, 4 AS x) ss
WHERE x < 4;
SELECT * FROM
(SELECT 1 AS t, 2 AS x
UNION
SELECT 2 AS t, 4 AS x) ss
WHERE x < 4;
explain (costs off)
SELECT * FROM
(SELECT 1 AS t, generate_series(1,10) AS x
UNION
SELECT 2 AS t, 4 AS x) ss
WHERE x < 4
ORDER BY x;
SELECT * FROM
(SELECT 1 AS t, generate_series(1,10) AS x
UNION
SELECT 2 AS t, 4 AS x) ss
WHERE x < 4
ORDER BY x;
explain (costs off)
SELECT * FROM
(SELECT 1 AS t, (random()*3)::int AS x
UNION
SELECT 2 AS t, 4 AS x) ss
WHERE x > 3;
SELECT * FROM
(SELECT 1 AS t, (random()*3)::int AS x
UNION
SELECT 2 AS t, 4 AS x) ss
WHERE x > 3;
explain (costs off)
SELECT * FROM
(SELECT distinct on (t) 1 AS t, 2 AS x
UNION
SELECT 2 AS t, 4 AS x) ss
WHERE x < 4
ORDER BY x;
SELECT * FROM
(SELECT distinct on (t) 1 AS t, 2 AS x
UNION
SELECT 2 AS t, 4 AS x) ss
WHERE x < 4
ORDER BY x;
explain (costs off)
SELECT * FROM
(SELECT 1.3 AS t, 2.5 AS x
UNION
SELECT 2 AS t, 4 AS x) ss
WHERE x < 4
ORDER BY x;
SELECT * FROM
(SELECT 1.3 AS t, 2.5 AS x
UNION
SELECT 2 AS t, 4 AS x) ss
WHERE x < 4
ORDER BY x;