explain-create-composite-index.txt

MariaDB [fun]> EXPLAIN SELECT * FROM users WHERE first_name = 'Martin' AND last_name = 'David';
+------+-------------+-------+------+----------------------+----------------------+---------+-------------+------+--------------------------+
| id   | select_type | table | type | possible_keys        | key                  | key_len | ref         | rows | Extra                    |
+------+-------------+-------+------+----------------------+----------------------+---------+-------------+------+--------------------------+
|    1 | SIMPLE      | users | ref  | first_and_last_names | first_and_last_names | 106     | const,const |    1 | Using where; Using index |
+------+-------------+-------+------+----------------------+----------------------+---------+-------------+------+--------------------------+
1 row in set (0.00 sec)