MariaDB [test]> create table t1 (i int);

Query OK, 0 rows affected (0.89 sec)

MariaDB [test]> analyze delete from t1 where 0;

Query OK, 0 rows affected (0.00 sec)

MariaDB [test]> analyze update t1 set i=1 where 0;

Query OK, 0 rows affected (0.00 sec)

MariaDB [test]> analyze select * from t1 where 0;

+------+-------------+-------+------+---------------+------+---------+------+------+--------+----------+------------+------------------+

| id   | select_type | table | type | possible_keys | key  | key_len | ref  | rows | r_rows | filtered | r_filtered | Extra            |

+------+-------------+-------+------+---------------+------+---------+------+------+--------+----------+------------+------------------+

|    1 | SIMPLE      | NULL  | NULL | NULL          | NULL | NULL    | NULL | NULL |   NULL |     NULL |       NULL | Impossible WHERE |

+------+-------------+-------+------+---------------+------+---------+------+------+--------+----------+------------+------------------+

1 row in set (0.00 sec)

MariaDB [test]> explain delete from t1 where 0;

+------+-------------+-------+------+---------------+------+---------+------+------+------------------+

| id   | select_type | table | type | possible_keys | key  | key_len | ref  | rows | Extra            |

+------+-------------+-------+------+---------------+------+---------+------+------+------------------+

|    1 | SIMPLE      | NULL  | NULL | NULL          | NULL | NULL    | NULL | NULL | Impossible WHERE |

+------+-------------+-------+------+---------------+------+---------+------+------+------------------+

1 row in set (0.01 sec)

MariaDB [test]> explain update t1 set i=1 where 0;

+------+-------------+-------+------+---------------+------+---------+------+------+------------------+

| id   | select_type | table | type | possible_keys | key  | key_len | ref  | rows | Extra            |

+------+-------------+-------+------+---------------+------+---------+------+------+------------------+

|    1 | SIMPLE      | NULL  | NULL | NULL          | NULL | NULL    | NULL | NULL | Impossible WHERE |

+------+-------------+-------+------+---------------+------+---------+------+------+------------------+

1 row in set (0.01 sec)

commit b95ec135533b13e921aa8de1b9c769d47b2efe60

Author: Alexey Botchkov <holyfoot@montyprogram.com>

Date:   Thu Jun 26 11:37:24 2014 +0500

Branch: 10.1