WHERE x.a='2001-01-01' AND z.a='2001-01-01 00:00:00';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE x system NULL NULL NULL NULL 1
1 SIMPLE y system NULL NULL NULL NULL 1
1 SIMPLE z system NULL NULL NULL NULL 1
Warnings:
Note 1003 select '2001-01-01 00:00:00' AS `a`,'2001-01-01 00:00:00' AS `a`,'2001-01-01 00:00:00' AS `a` from `test`.`t1` `x` join `test`.`t1` `y` join `test`.`t1` `z` where 1