mysql> explain select First_Name from Customers where Last_Name like '%fred%';
+-----------+------+---------------+------+---------+------+------+-------------+
| table     | type | possible_keys | key  | key_len | ref  | rows | Extra       |
+-----------+------+---------------+------+---------+------+------+-------------+
| Customers | ALL  | NULL          | NULL |    NULL | NULL | 6275 | Using where |
+-----------+------+---------------+------+---------+------+------+-------------+
1 row in set (0.00 sec)