當(dāng)?shù)诙€(gè)參數(shù)INTERVAL形式調(diào)用,ADDDATE() 是DATE_ADD()的同義詞。 相關(guān)函數(shù)SUBDATE()是DATE_SUB()同義詞。 有關(guān)INTERVAL 參數(shù)信息,請(qǐng)參閱DATE_ADD()的討論。
mysql> SELECT DATE_ADD('1998-01-02', INTERVAL 31 DAY); +---------------------------------------------------------+ | DATE_ADD('1998-01-02', INTERVAL 31 DAY) | +---------------------------------------------------------+ | 1998-02-02 | +---------------------------------------------------------+ 1 row in set (0.00 sec) mysql> SELECT ADDDATE('1998-01-02', INTERVAL 31 DAY); +---------------------------------------------------------+ | ADDDATE('1998-01-02', INTERVAL 31 DAY) | +---------------------------------------------------------+ | 1998-02-02 | +---------------------------------------------------------+ 1 row in set (0.00 sec)
當(dāng)?shù)诙€(gè)參數(shù)days 的形式調(diào)用時(shí),MySQL將其視為整數(shù)天數(shù)添加到expr。
mysql> SELECT ADDDATE('1998-01-02', 31); +---------------------------------------------------------+ | DATE_ADD('1998-01-02', INTERVAL 31 DAY) | +---------------------------------------------------------+ | 1998-02-02 | +---------------------------------------------------------+ 1 row in set (0.00 sec)