#
# Bug #17059925 : UNIONS COMPUTES ROWS_EXAMINED INCORRECTLY
#
SET @old_slow_query_log= @@global.slow_query_log;
SET @old_log_output= @@global.log_output;
SET @old_long_query_time= @@long_query_time;
SET GLOBAL log_output= "TABLE";
SET GLOBAL slow_query_log= ON;
SET SESSION long_query_time= 0;
CREATE TABLE t17059925 (a INT, KEY a(a));
CREATE TABLE t2 (b INT);
CREATE TABLE t3 (c INT);
INSERT INTO t17059925 VALUES (1);
INSERT INTO t2 VALUES (4), (5), (6);
INSERT INTO t3 VALUES (7), (8), (9);
TRUNCATE table mysql.slow_log;
SELECT sleep(0.5) FROM t17059925 UNION SELECT * FROM t2 UNION SELECT * FROM t3;
sleep(0.5)
0
4
5
6
7
8
9
SELECT sleep(0.5) FROM t17059925 UNION ALL SELECT * FROM t2 UNION ALL SELECT * FROM t3;
sleep(0.5)
0
4
5
6
7
8
9
CREATE FUNCTION t17059925_func1 (a INT)
RETURNS INT DETERMINISTIC
RETURN a;
SELECT t17059925_func1(1), sleep(0.5);
t17059925_func1(1)	sleep(0.5)
1	0
SELECT sleep(0.5) from t17059925 UNION SELECT t17059925_func1(1);
sleep(0.5)
0
1
SELECT * FROM (SELECT t17059925_func1(1)) t WHERE 1= 0 UNION SELECT sleep(0.5);
t17059925_func1(1)
0
SELECT sleep(0.5) FROM t17059925 UNION SELECT * FROM (SELECT t17059925_func1(1)) t WHERE 1= 0 UNION SELECT t17059925_func1(1);
sleep(0.5)
0
1
SELECT 1 FROM dual WHERE 1= 0 UNION SELECT sleep(0.5);
1
0
SELECT sleep(0.5) FROM t17059925 UNION SELECT 1 FROM dual WHERE 1= 0 UNION SELECT * FROM t2;
sleep(0.5)
0
4
5
6
EXPLAIN SELECT t17059925_func1(1);
id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	ROWS	NULL	NULL	No tables used
Warnings:
Note	1003	/* select#1 */ select `t17059925_func1`(1) AS `t17059925_func1(1)`
EXPLAIN SELECT * FROM t17059925 UNION SELECT t17059925_func1(1);
id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
1	PRIMARY	t17059925	NULL	index	NULL	a	5	ROWS	#	#	Using index
2	UNION	NULL	NULL	NULL	NULL	NULL	NULL	ROWS	#	#	No tables used
NULL	UNION RESULT	<union1,2>	NULL	ALL	NULL	NULL	NULL	ROWS	#	#	Using temporary
Warnings:
Note	1003	/* select#1 */ select `test`.`t17059925`.`a` AS `a` from `test`.`t17059925` union /* select#2 */ select `t17059925_func1`(1) AS `t17059925_func1(1)`
SELECT * FROM t17059925 WHERE a= 10 AND a= 20 UNION SELECT sleep(0.5);
a
0
SELECT * FROM t17059925 WHERE a= 10 UNION SELECT sleep(0.5);
a
0
SELECT * FROM (SELECT * FROM t17059925 WHERE a= 10) t WHERE a = 10 UNION SELECT sleep(0.5);
a
0
SELECT sleep(0.5) FROM t17059925 UNION SELECT * FROM t17059925 WHERE a= 10 AND a= 20 UNION SELECT * FROM t2;
sleep(0.5)
0
4
5
6
SELECT sleep(0.5) FROM t17059925 UNION ALL SELECT * FROM t17059925 WHERE a= 10 AND a= 20 UNION ALL SELECT * FROM t2;
sleep(0.5)
0
4
5
6
SELECT sleep(0.5) FROM t17059925 UNION SELECT * FROM (SELECT * FROM t17059925 WHERE a= 10) t WHERE a = 10 UNION SELECT * from t2;
sleep(0.5)
0
4
5
6
EXPLAIN SELECT * FROM t17059925 WHERE a= 10 AND a= 20;
id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	ROWS	NULL	NULL	Impossible WHERE
Warnings:
Note	1003	/* select#1 */ select `test`.`t17059925`.`a` AS `a` from `test`.`t17059925` where false
EXPLAIN SELECT * FROM t17059925 UNION SELECT * FROM t17059925 WHERE a= 10 AND a= 20;
id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
1	PRIMARY	t17059925	NULL	index	NULL	a	5	ROWS	#	#	Using index
2	UNION	NULL	NULL	NULL	NULL	NULL	NULL	ROWS	#	#	Impossible WHERE
NULL	UNION RESULT	<union1,2>	NULL	ALL	NULL	NULL	NULL	ROWS	#	#	Using temporary
Warnings:
Note	1003	/* select#1 */ select `test`.`t17059925`.`a` AS `a` from `test`.`t17059925` union /* select#2 */ select `test`.`t17059925`.`a` AS `a` from `test`.`t17059925` where false
SELECT sql_text, rows_examined FROM mysql.slow_log WHERE (sql_text LIKE '%SELECT%t17059925%'
       AND sql_text NOT LIKE '%EXPLAIN%') OR sql_text LIKE '%dual%';
sql_text	rows_examined
SELECT * FROM (SELECT * FROM t17059925 WHERE a= 10) t WHERE a = 10 UNION SELECT sleep(0.5)	2
SELECT * FROM (SELECT t17059925_func1(1)) t WHERE 1= 0 UNION SELECT sleep(0.5)	3
SELECT * FROM t17059925 WHERE a= 10 AND a= 20 UNION SELECT sleep(0.5)	2
SELECT * FROM t17059925 WHERE a= 10 UNION SELECT sleep(0.5)	2
SELECT 1 FROM dual WHERE 1= 0 UNION SELECT sleep(0.5)	2
SELECT sleep(0.5) FROM t17059925 UNION ALL SELECT * FROM t17059925 WHERE a= 10 AND a= 20 UNION ALL SELECT * FROM t2	4
SELECT sleep(0.5) FROM t17059925 UNION ALL SELECT * FROM t2 UNION ALL SELECT * FROM t3	7
SELECT sleep(0.5) FROM t17059925 UNION SELECT * FROM (SELECT * FROM t17059925 WHERE a= 10) t WHERE a = 10 UNION SELECT * from t2	8
SELECT sleep(0.5) FROM t17059925 UNION SELECT * FROM (SELECT t17059925_func1(1)) t WHERE 1= 0 UNION SELECT t17059925_func1(1)	5
SELECT sleep(0.5) FROM t17059925 UNION SELECT * FROM t17059925 WHERE a= 10 AND a= 20 UNION SELECT * FROM t2	8
SELECT sleep(0.5) FROM t17059925 UNION SELECT * FROM t2 UNION SELECT * FROM t3	14
SELECT sleep(0.5) FROM t17059925 UNION SELECT 1 FROM dual WHERE 1= 0 UNION SELECT * FROM t2	8
SELECT sleep(0.5) from t17059925 UNION SELECT t17059925_func1(1)	4
SELECT t17059925_func1(1), sleep(0.5)	1
DROP FUNCTION t17059925_func1;
DROP TABLE t17059925, t2, t3;
SET @@long_query_time= @old_long_query_time;
SET @@global.log_output= @old_log_output;
SET @@global.slow_query_log= @old_slow_query_log;