where id in (select id from t1 as x1 where (t1.cur_date is null));
where id in (select id from t1 as x1 where (t1.cur_date is null));
id select_type table type possible_keys key key_len ref rows filtered Extra
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL 2 100.00 Using where; Start temporary
1 PRIMARY t1 ALL NULL NULL NULL NULL 2 100.00 Using where
1 PRIMARY x1 ALL NULL NULL NULL NULL 2 100.00 Using where; End temporary
1 PRIMARY x1 ALL NULL NULL NULL NULL 2 100.00 Using where; Start temporary; End temporary
Warnings:
Warnings:
Note 1276 Field or reference 'test.t1.cur_date' of SELECT #2 was resolved in SELECT #1
Note 1276 Field or reference 'test.t1.cur_date' of SELECT #2 was resolved in SELECT #1
Note 1003 select `test`.`t1`.`id` AS `id`,`test`.`t1`.`cur_date` AS `cur_date` from `test`.`t1` semi join (`test`.`t1` `x1`) where ((`test`.`x1`.`id` = `test`.`t1`.`id`) and (`test`.`t1`.`cur_date` = 0))
Note 1003 select `test`.`t1`.`id` AS `id`,`test`.`t1`.`cur_date` AS `cur_date` from `test`.`t1` semi join (`test`.`t1` `x1`) where ((`test`.`x1`.`id` = `test`.`t1`.`id`) and (`test`.`t1`.`cur_date` = 0))
...
@@ -550,8 +550,8 @@ explain extended
...
@@ -550,8 +550,8 @@ explain extended
select * from t2
select * from t2
where id in (select id from t2 as x1 where (t2.cur_date is null));
where id in (select id from t2 as x1 where (t2.cur_date is null));
id select_type table type possible_keys key key_len ref rows filtered Extra
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t2 ALL NULL NULL NULL NULL 2 100.00 Using where; Start temporary
1 PRIMARY t2 ALL NULL NULL NULL NULL 2 100.00 Using where
1 PRIMARY x1 ALL NULL NULL NULL NULL 2 100.00 Using where; End temporary
1 PRIMARY x1 ALL NULL NULL NULL NULL 2 100.00 Using where; Start temporary; End temporary
Warnings:
Warnings:
Note 1276 Field or reference 'test.t2.cur_date' of SELECT #2 was resolved in SELECT #1
Note 1276 Field or reference 'test.t2.cur_date' of SELECT #2 was resolved in SELECT #1
Note 1003 select `test`.`t2`.`id` AS `id`,`test`.`t2`.`cur_date` AS `cur_date` from `test`.`t2` semi join (`test`.`t2` `x1`) where ((`test`.`x1`.`id` = `test`.`t2`.`id`) and (`test`.`t2`.`cur_date` = 0))
Note 1003 select `test`.`t2`.`id` AS `id`,`test`.`t2`.`cur_date` AS `cur_date` from `test`.`t2` semi join (`test`.`t2` `x1`) where ((`test`.`x1`.`id` = `test`.`t2`.`id`) and (`test`.`t2`.`cur_date` = 0))