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--
-- JOIN
-- Test JOIN clauses
--
CREATE TABLE J1_TBL (
i integer,
j integer,
t text
);
CREATE TABLE J2_TBL (
i integer,
k integer
);
INSERT INTO J1_TBL VALUES (1, 4, 'one');
INSERT INTO J1_TBL VALUES (2, 3, 'two');
INSERT INTO J1_TBL VALUES (3, 2, 'three');
INSERT INTO J1_TBL VALUES (4, 1, 'four');
INSERT INTO J1_TBL VALUES (5, 0, 'five');
INSERT INTO J1_TBL VALUES (6, 6, 'six');
INSERT INTO J1_TBL VALUES (7, 7, 'seven');
INSERT INTO J1_TBL VALUES (8, 8, 'eight');
INSERT INTO J1_TBL VALUES (0, NULL, 'zero');
INSERT INTO J1_TBL VALUES (NULL, NULL, 'null');
INSERT INTO J1_TBL VALUES (NULL, 0, 'zero');
INSERT INTO J2_TBL VALUES (1, -1);
INSERT INTO J2_TBL VALUES (2, 2);
INSERT INTO J2_TBL VALUES (3, -3);
INSERT INTO J2_TBL VALUES (2, 4);
INSERT INTO J2_TBL VALUES (5, -5);
INSERT INTO J2_TBL VALUES (5, -5);
INSERT INTO J2_TBL VALUES (0, NULL);
INSERT INTO J2_TBL VALUES (NULL, NULL);
INSERT INTO J2_TBL VALUES (NULL, 0);
--
-- CORRELATION NAMES
-- Make sure that table/column aliases are supported
-- before diving into more complex join syntax.
--
SELECT '' AS "xxx", *
FROM J1_TBL AS tx;
SELECT '' AS "xxx", *
FROM J1_TBL tx;
SELECT '' AS "xxx", *
FROM J1_TBL AS t1 (a, b, c);
SELECT '' AS "xxx", *
FROM J1_TBL t1 (a, b, c);
SELECT '' AS "xxx", *
FROM J1_TBL t1 (a, b, c), J2_TBL t2 (d, e);
SELECT '' AS "xxx", t1.a, t2.e
FROM J1_TBL t1 (a, b, c), J2_TBL t2 (d, e)
WHERE t1.a = t2.d;
--
-- CROSS JOIN
-- Qualifications are not allowed on cross joins,
-- which degenerate into a standard unqualified inner join.
--
SELECT '' AS "xxx", *
FROM J1_TBL CROSS JOIN J2_TBL;
-- ambiguous column
SELECT '' AS "xxx", i, k, t
FROM J1_TBL CROSS JOIN J2_TBL;
-- resolve previous ambiguity by specifying the table name
SELECT '' AS "xxx", t1.i, k, t
FROM J1_TBL t1 CROSS JOIN J2_TBL t2;
SELECT '' AS "xxx", ii, tt, kk
FROM (J1_TBL CROSS JOIN J2_TBL)
AS tx (ii, jj, tt, ii2, kk);
SELECT '' AS "xxx", tx.ii, tx.jj, tx.kk
FROM (J1_TBL t1 (a, b, c) CROSS JOIN J2_TBL t2 (d, e))
AS tx (ii, jj, tt, ii2, kk);
SELECT '' AS "xxx", *
FROM J1_TBL CROSS JOIN J2_TBL a CROSS JOIN J2_TBL b;
--
--
-- Inner joins (equi-joins)
--
--
--
-- Inner joins (equi-joins) with USING clause
-- The USING syntax changes the shape of the resulting table
-- by including a column in the USING clause only once in the result.
--
-- Inner equi-join on specified column
SELECT '' AS "xxx", *
FROM J1_TBL INNER JOIN J2_TBL USING (i);
-- Same as above, slightly different syntax
SELECT '' AS "xxx", *
FROM J1_TBL JOIN J2_TBL USING (i);
SELECT '' AS "xxx", *
FROM J1_TBL t1 (a, b, c) JOIN J2_TBL t2 (a, d) USING (a)
ORDER BY a, d;
SELECT '' AS "xxx", *
FROM J1_TBL t1 (a, b, c) JOIN J2_TBL t2 (a, b) USING (b)
ORDER BY b, t1.a;
--
-- NATURAL JOIN
-- Inner equi-join on all columns with the same name
--
SELECT '' AS "xxx", *
FROM J1_TBL NATURAL JOIN J2_TBL;
SELECT '' AS "xxx", *
FROM J1_TBL t1 (a, b, c) NATURAL JOIN J2_TBL t2 (a, d);
SELECT '' AS "xxx", *
FROM J1_TBL t1 (a, b, c) NATURAL JOIN J2_TBL t2 (d, a);
-- mismatch number of columns
-- currently, Postgres will fill in with underlying names
SELECT '' AS "xxx", *
FROM J1_TBL t1 (a, b) NATURAL JOIN J2_TBL t2 (a);
--
-- Inner joins (equi-joins)
--
SELECT '' AS "xxx", *
FROM J1_TBL JOIN J2_TBL ON (J1_TBL.i = J2_TBL.i);
SELECT '' AS "xxx", *
FROM J1_TBL JOIN J2_TBL ON (J1_TBL.i = J2_TBL.k);
--
-- Non-equi-joins
--
SELECT '' AS "xxx", *
FROM J1_TBL JOIN J2_TBL ON (J1_TBL.i <= J2_TBL.k);
--
-- Outer joins
-- Note that OUTER is a noise word
--
SELECT '' AS "xxx", *
FROM J1_TBL LEFT OUTER JOIN J2_TBL USING (i)
ORDER BY i, k, t;
SELECT '' AS "xxx", *
FROM J1_TBL LEFT JOIN J2_TBL USING (i)
ORDER BY i, k, t;
SELECT '' AS "xxx", *
FROM J1_TBL RIGHT OUTER JOIN J2_TBL USING (i);
SELECT '' AS "xxx", *
FROM J1_TBL RIGHT JOIN J2_TBL USING (i);
SELECT '' AS "xxx", *
FROM J1_TBL FULL OUTER JOIN J2_TBL USING (i)
ORDER BY i, k, t;
SELECT '' AS "xxx", *
FROM J1_TBL FULL JOIN J2_TBL USING (i)
ORDER BY i, k, t;
SELECT '' AS "xxx", *
FROM J1_TBL LEFT JOIN J2_TBL USING (i) WHERE (k = 1);
SELECT '' AS "xxx", *
FROM J1_TBL LEFT JOIN J2_TBL USING (i) WHERE (i = 1);
--
-- More complicated constructs
--
--
-- Multiway full join
--
CREATE TABLE t1 (name TEXT, n INTEGER);
CREATE TABLE t2 (name TEXT, n INTEGER);
CREATE TABLE t3 (name TEXT, n INTEGER);
INSERT INTO t1 VALUES ( 'aa', 11 );
INSERT INTO t2 VALUES ( 'aa', 12 );
INSERT INTO t2 VALUES ( 'bb', 22 );
INSERT INTO t2 VALUES ( 'dd', 42 );
INSERT INTO t3 VALUES ( 'aa', 13 );
INSERT INTO t3 VALUES ( 'bb', 23 );
INSERT INTO t3 VALUES ( 'cc', 33 );
SELECT * FROM t1 FULL JOIN t2 USING (name) FULL JOIN t3 USING (name);
--
-- Test interactions of join syntax and subqueries
--
-- Basic cases (we expect planner to pull up the subquery here)
SELECT * FROM
(SELECT * FROM t2) as s2
INNER JOIN
(SELECT * FROM t3) s3
USING (name);
SELECT * FROM
(SELECT * FROM t2) as s2
LEFT JOIN
(SELECT * FROM t3) s3
USING (name);
SELECT * FROM
(SELECT * FROM t2) as s2
FULL JOIN
(SELECT * FROM t3) s3
USING (name);
-- Cases with non-nullable expressions in subquery results;
-- make sure these go to null as expected
SELECT * FROM
(SELECT name, n as s2_n, 2 as s2_2 FROM t2) as s2
NATURAL INNER JOIN
(SELECT name, n as s3_n, 3 as s3_2 FROM t3) s3;
SELECT * FROM
(SELECT name, n as s2_n, 2 as s2_2 FROM t2) as s2
NATURAL LEFT JOIN
(SELECT name, n as s3_n, 3 as s3_2 FROM t3) s3;
SELECT * FROM
(SELECT name, n as s2_n, 2 as s2_2 FROM t2) as s2
NATURAL FULL JOIN
(SELECT name, n as s3_n, 3 as s3_2 FROM t3) s3;
SELECT * FROM
(SELECT name, n as s1_n, 1 as s1_1 FROM t1) as s1
NATURAL INNER JOIN
(SELECT name, n as s2_n, 2 as s2_2 FROM t2) as s2
NATURAL INNER JOIN
(SELECT name, n as s3_n, 3 as s3_2 FROM t3) s3;
SELECT * FROM
(SELECT name, n as s1_n, 1 as s1_1 FROM t1) as s1
NATURAL FULL JOIN
(SELECT name, n as s2_n, 2 as s2_2 FROM t2) as s2
NATURAL FULL JOIN
(SELECT name, n as s3_n, 3 as s3_2 FROM t3) s3;
SELECT * FROM
(SELECT name, n as s1_n FROM t1) as s1
NATURAL FULL JOIN
(SELECT * FROM
(SELECT name, n as s2_n FROM t2) as s2
NATURAL FULL JOIN
(SELECT name, n as s3_n FROM t3) as s3
) ss2;
SELECT * FROM
(SELECT name, n as s1_n FROM t1) as s1
NATURAL FULL JOIN
(SELECT * FROM
(SELECT name, n as s2_n, 2 as s2_2 FROM t2) as s2
NATURAL FULL JOIN
(SELECT name, n as s3_n FROM t3) as s3
) ss2;
-- Test for propagation of nullability constraints into sub-joins
create temp table x (x1 int, x2 int);
insert into x values (1,11);
insert into x values (2,22);
insert into x values (3,null);
insert into x values (4,44);
insert into x values (5,null);
create temp table y (y1 int, y2 int);
insert into y values (1,111);
insert into y values (2,222);
insert into y values (3,333);
insert into y values (4,null);
select * from x;
select * from y;
select * from x left join y on (x1 = y1 and x2 is not null);
select * from x left join y on (x1 = y1 and y2 is not null);
select * from (x left join y on (x1 = y1)) left join x xx(xx1,xx2)
on (x1 = xx1);
select * from (x left join y on (x1 = y1)) left join x xx(xx1,xx2)
on (x1 = xx1 and x2 is not null);
select * from (x left join y on (x1 = y1)) left join x xx(xx1,xx2)
on (x1 = xx1 and y2 is not null);
select * from (x left join y on (x1 = y1)) left join x xx(xx1,xx2)
on (x1 = xx1 and xx2 is not null);
-- these should NOT give the same answers as above
select * from (x left join y on (x1 = y1)) left join x xx(xx1,xx2)
on (x1 = xx1) where (x2 is not null);
select * from (x left join y on (x1 = y1)) left join x xx(xx1,xx2)
on (x1 = xx1) where (y2 is not null);
select * from (x left join y on (x1 = y1)) left join x xx(xx1,xx2)
on (x1 = xx1) where (xx2 is not null);
--
-- regression test: check for bug with propagation of implied equality
-- to outside an IN
--
select count(*) from tenk1 a where unique1 in
(select unique1 from tenk1 b join tenk1 c using (unique1)
where b.unique2 = 42);
--
-- Clean up
--
DROP TABLE t1;
DROP TABLE t2;
DROP TABLE t3;
DROP TABLE J1_TBL;
DROP TABLE J2_TBL;
-- Both DELETE and UPDATE allow the specification of additional tables
-- to "join" against to determine which rows should be modified.
CREATE TEMP TABLE t1 (a int, b int);
CREATE TEMP TABLE t2 (a int, b int);
CREATE TEMP TABLE t3 (x int, y int);
INSERT INTO t1 VALUES (5, 10);
INSERT INTO t1 VALUES (15, 20);
INSERT INTO t1 VALUES (100, 100);
INSERT INTO t1 VALUES (200, 1000);
INSERT INTO t2 VALUES (200, 2000);
INSERT INTO t3 VALUES (5, 20);
INSERT INTO t3 VALUES (6, 7);
INSERT INTO t3 VALUES (7, 8);
INSERT INTO t3 VALUES (500, 100);
DELETE FROM t3 USING t1 table1 WHERE t3.x = table1.a;
SELECT * FROM t3;
DELETE FROM t3 USING t1 JOIN t2 USING (a) WHERE t3.x > t1.a;
SELECT * FROM t3;
DELETE FROM t3 USING t3 t3_other WHERE t3.x = t3_other.x AND t3.y = t3_other.y;
SELECT * FROM t3;
--
-- regression test for 8.1 merge right join bug
--
CREATE TEMP TABLE tt1 ( tt1_id int4, joincol int4 );
INSERT INTO tt1 VALUES (1, 11);
INSERT INTO tt1 VALUES (2, NULL);
CREATE TEMP TABLE tt2 ( tt2_id int4, joincol int4 );
INSERT INTO tt2 VALUES (21, 11);
INSERT INTO tt2 VALUES (22, 11);
set enable_hashjoin to off;
set enable_nestloop to off;
-- these should give the same results
select tt1.*, tt2.* from tt1 left join tt2 on tt1.joincol = tt2.joincol;
select tt1.*, tt2.* from tt2 right join tt1 on tt1.joincol = tt2.joincol;
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