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#
# Bug#27182010 SUBQUERY INCORRECTLY SHOWS DUPLICATE VALUES ON SUBQUERIES
#
CREATE TABLE p (Id INT,PRIMARY KEY (Id));
INSERT INTO p VALUES (1);
# Test UNIQUE KEY with NULL values
CREATE TABLE s (Id INT, u INT, UNIQUE KEY o(Id, u) );
INSERT INTO s VALUES (1, NULL),(1, NULL);
EXPLAIN SELECT p.Id FROM (p) WHERE p.Id IN (
SELECT s.Id FROM s WHERE Id=1 AND u IS NULL)ORDER BY Id DESC;
id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
1	SIMPLE	p	NULL	const	PRIMARY	PRIMARY	4	const	1	100.00	Using index
1	SIMPLE	s	NULL	ref	o	o	10	const,const	2	100.00	Using where; Using index; FirstMatch(p)
Warnings:
Note	1003	/* select#1 */ select '1' AS `Id` from `test`.`p` semi join (`test`.`s`) where ((`test`.`s`.`Id` = 1) and isnull(`test`.`s`.`u`)) order by '1' desc
EXPLAIN SELECT p.Id FROM (p) WHERE p.Id IN (
SELECT s.Id FROM s WHERE Id=1 AND u IS NOT NULL) ORDER BY Id DESC;
id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
1	SIMPLE	p	NULL	const	PRIMARY	PRIMARY	4	const	1	100.00	Using index
1	SIMPLE	s	NULL	range	o	o	10	NULL	1	100.00	Using where; Using index; FirstMatch(p)
Warnings:
Note	1003	/* select#1 */ select '1' AS `Id` from `test`.`p` semi join (`test`.`s`) where ((`test`.`s`.`Id` = 1) and (`test`.`s`.`u` is not null)) order by '1' desc
SELECT p.Id FROM (p) WHERE p.Id IN (
SELECT s.Id FROM s WHERE Id=1 AND u IS NULL)ORDER BY Id DESC;
Id
1
SELECT p.Id FROM (p) WHERE p.Id IN (
SELECT s.Id FROM s WHERE Id=1 AND u IS NOT NULL) ORDER BY Id DESC;
Id
# UNIQUE KEY without NULL values
CREATE TABLE s1 (Id INT, u INT, UNIQUE KEY o(Id, u) );
INSERT INTO s1 VALUES (1, 2),(1, 3);
EXPLAIN SELECT p.Id FROM (p) WHERE p.Id IN (
SELECT s1.Id FROM s1 WHERE Id=1 AND u IS NOT NULL) ORDER BY Id DESC;
id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
1	SIMPLE	p	NULL	const	PRIMARY	PRIMARY	4	const	1	100.00	Using index
1	SIMPLE	s1	NULL	ref	o	o	5	const	2	50.00	Using where; Using index; FirstMatch(p)
Warnings:
Note	1003	/* select#1 */ select '1' AS `Id` from `test`.`p` semi join (`test`.`s1`) where ((`test`.`s1`.`Id` = 1) and (`test`.`s1`.`u` is not null)) order by '1' desc
EXPLAIN SELECT p.Id FROM (p) WHERE p.Id IN (
SELECT s1.Id FROM s1 WHERE Id=1 AND u != 1) ORDER BY Id DESC;
id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
1	SIMPLE	p	NULL	const	PRIMARY	PRIMARY	4	const	1	100.00	Using index
1	SIMPLE	s1	NULL	ref	o	o	5	const	3	50.00	Using where; Using index; FirstMatch(p)
Warnings:
Note	1003	/* select#1 */ select '1' AS `Id` from `test`.`p` semi join (`test`.`s1`) where ((`test`.`s1`.`Id` = 1) and (`test`.`s1`.`u` <> 1)) order by '1' desc
SELECT p.Id FROM (p) WHERE p.Id IN (
SELECT s1.Id FROM s1 WHERE Id=1 AND u IS NOT NULL) ORDER BY Id DESC;
Id
1
SELECT p.Id FROM (p) WHERE p.Id IN (
SELECT s1.Id FROM s1 WHERE Id=1 AND u != 1) ORDER BY Id DESC;
Id
1
# NON UNIQUE KEY Scenario
CREATE TABLE s2 (Id INT, u INT, KEY o(Id, u) );
INSERT INTO s2 VALUES (1, NULL),(1, NULL);
#UNIQUE KEY with NON NULL FIELDS
CREATE TABLE s3 (Id INT NOT NULL, u INT NOT NULL, UNIQUE KEY o(Id, u));
INSERT INTO s3 VALUES (1, 2),(1, 3);
EXPLAIN SELECT p.Id FROM (p) WHERE p.Id IN (
SELECT s.Id FROM s2 s WHERE Id=1 AND u IS NULL) ORDER BY Id DESC;
id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
1	SIMPLE	p	NULL	const	PRIMARY	PRIMARY	4	const	1	100.00	Using index
1	SIMPLE	s	NULL	ref	o	o	10	const,const	2	100.00	Using where; Using index; FirstMatch(p)
Warnings:
Note	1003	/* select#1 */ select '1' AS `Id` from `test`.`p` semi join (`test`.`s2` `s`) where ((`test`.`s`.`Id` = 1) and isnull(`test`.`s`.`u`)) order by '1' desc
EXPLAIN SELECT p.Id FROM (p) WHERE p.Id IN (
SELECT s.Id FROM s3 s WHERE Id=1 AND u IS NOT NULL)
ORDER BY Id DESC;
id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
1	SIMPLE	p	NULL	const	PRIMARY	PRIMARY	4	const	1	100.00	Using index
1	SIMPLE	s	NULL	ref	o	o	4	const	2	50.00	Using where; Using index; FirstMatch(p)
Warnings:
Note	1003	/* select#1 */ select '1' AS `Id` from `test`.`p` semi join (`test`.`s3` `s`) where ((`test`.`s`.`Id` = 1) and (`test`.`s`.`u` is not null)) order by '1' desc
SELECT p.Id FROM (p) WHERE p.Id IN (
SELECT s.Id FROM s2 s WHERE Id=1 AND u IS NULL) ORDER BY Id DESC;
Id
1
SELECT p.Id FROM (p) WHERE p.Id IN (
SELECT s.Id FROM s3 s WHERE Id=1 AND u IS NOT NULL)
ORDER BY Id DESC;
Id
1
DROP TABLE p, s, s1, s2, s3;