Add one day to the date literal '2004-13-12'; next show the error messages.
mysql> mysql> mysql> SELECT '2004-13-12' + INTERVAL 1 DAY; +-------------------------------+ | '2004-13-12' + INTERVAL 1 DAY | +-------------------------------+ | NULL | +-------------------------------+ 1 row in set, 1 warning (0.00 sec) mysql> mysql>