changedetail_delete.sql

来自「用vb.net写的基于c/s结构的进销存程序设计源代码」· SQL 代码 · 共 19 行

CREATE TRIGGER ChangeDetail_Delete
ON ChangeDetail
FOR DELETE
AS
/* 如果删除记录数是0就结束触发程序 */ 
IF @@ROWCOUNT = 0 RETURN
/* 定义变量 
@ProductID : 商品编号
@Quantity : 数量
*/
DECLARE @ProductID Char(10)
DECLARE @Quantity Decimal(12, 0)
/* 找出删除的出货单号给ChangeID, 商品编号给ProductID, 数量给Quantity */
SELECT @ProductID = ProductID, @Quantity = ChangeQuantity
FROM deleted
/*计算库存量*/
UPDATE Product SET Quantity = Quantity - @Quantity
WHERE ProductID = @ProductID