第二个删除型触发器.sql

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/*定义第二个删除型触发器*/
CREATE trigger t_products
ON products
FOR DELETE
AS

/*显示信息代表触发器执行*/
PRINT 'DELETE trigger on the products table is executing '

/*声明一个临时变量用来存储将要删除表的顺序*/
DECLARE @product_id char (4),
@mesg varchar (40)
SELECT @product_id=productid
FROM deleted
GROUP BY productid
IF @@rowcount = 0
BEGIN
PRINT 'no rows affected on the products table'
RETURN
END

/*删除产品记录*/
SELECT @mesg='deleting discounts for products' + @mesg
PRINT @mesg
DELETE discounts
WHERE productid=@product_id