MariaDB [t_girl]> select count(email) from email_list where email_suffix = '56.com'; +--------------+ | count(email) | +--------------+ | 1960 | +--------------+ 1 row in set (0.02 sec)
MariaDB实现函数索引(二)
| 103 | const | 1959 | Using index condition | +------+-------------+------------+------+------------------+------------------+---------+-------+------+-----------------------+ 1 row in set (0.02 sec)