+----+--------------+--------------+--------+------------------+---------+---------+----------+------+-------------+ | id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra | +----+--------------+--------------+--------+------------------+---------+---------+----------+------+-------------+ | 1 | PRIMARY | | ALL | NULL | NULL | NULL | NULL | 167 | | | 1 | PRIMARY | s | eq_ref | PRIMARY,licensed | PRIMARY | 4 | r.series | 1 | Using where | | 2 | DERIVED | releases | ref | subber | subber | 4 | | 115 | Using where | | 3 | UNION | releases | ref | subber2 | subber2 | 5 | | 46 | Using where | | 4 | UNION | releases | ref | subber3 | subber3 | 5 | | 1 | Using where | |NULL | UNION RESULT | | ALL | NULL | NULL | NULL | NULL | NULL | | +----+--------------+--------------+--------+------------------+---------+---------+----------+------+-------------+ 6 rows in set (0.01 sec) +----+-------------+-------+------+-------------------------------+--------+---------+-----------------------+------+-------------+ | id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra | +----+-------------+-------+------+-------------------------------+--------+---------+-----------------------+------+-------------+ | 1 | SIMPLE | s | ALL | PRIMARY,licensed | NULL | NULL | NULL | 4284 | Using where | | 1 | SIMPLE | r | ref | series,subber,subber2,subber3 | series | 4 | zephor_manganews.s.id | 7 | Using where | +----+-------------+-------+------+-------------------------------+--------+---------+-----------------------+------+-------------+ 2 rows in set (0.00 sec)