餐饮的管理系统 餐饮的管理系统云部署(32)

hàoddbhcàipǐnbiānhàocpbhfēnshèlewài键 。另wàiwàideshè由触发器或biān程语言来shè定 。以订dānbiǎodd为例触发器shè置方如下:
CREATE TRIGGER insert_xs ON dd
AFTER INSERT
AS
IF EXISTS
(SELECT * FROM INSERTED
WHERE zh IN (SELECT zh FROM zt))
PRINT '添加成gōng!’
ELSE
BEGIN
PRINT 'zhuōhàocúnzàidezhuōhào符!’
ROLLBACK TRANSACTION
END
同样以对diǎncàibiǎoshè置一个触发器yào求dcdedānbiānhàoddbhcàipǐnbiānhàocpbh也具yǒucānzhào性 。cānzhàozhěngshìyòng来维护相关shùbiǎo之间shù一致性deshǒu段,通过shí现引yòngzhěng性,