1 2 3 4 5 6 7 8 9 10
|
mysql> explain select actor_id, (select @foo := coalesce(@foo, 0) + 1 from sakila.actor) as foo from sakila.actor;
+----+----------------------+-------+-------+---------------+---------+---------+------+------+-------------+
| id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra |
+----+----------------------+-------+-------+---------------+---------+---------+------+------+-------------+
| 1 | PRIMARY | actor | index | NULL | PRIMARY | 2 | NULL | 200 | Using index |
| 2 | UNCACHEABLE SUBQUERY | actor | index | NULL | PRIMARY | 2 | NULL | 200 | Using index |
+----+----------------------+-------+-------+---------------+---------+---------+------+------+-------------+
2 rows in set (0.00 sec)
mysql> notee
|