隐式转换问题

CREATE TABLE `v` (
  `itov` varchar(32) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8

mysql> insert into v values('20180119000133312');
Query OK, 1 row affected (0.06 sec)

mysql> insert into v values('20180119000133313');
Query OK, 1 row affected (0.00 sec)

mysql> insert into v values('20180119000133314');
Query OK, 1 row affected (0.01 sec)


sql_mode      | STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION |

mysql>  select * from v where itov=20180119000133310;
+-------------------+
| itov              |
+-------------------+
| 20180119000133312 |
| 20180119000133313 |
| 20180119000133314 |
+-------------------+
3 rows in set (0.00 sec)

mysql> select * from v where itov='20180119000133310';
Empty set (0.00 sec)