purchasedetail_delete.sql

用vb.net写的基于c/s结构的进销存程序设计源代码

CREATE TRIGGER PurchaseDetail_Delete
ON PurchaseDetail
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 
@PurchaseID : 进货单号
@PurchaseProperty : 进货单属性
@ProductID : 商品编号
@Quantity : 数量
*/
DECLARE @PurchaseID Char(10), @PurchaseProperty Char(1), @ProductID Char(10)
DECLARE @Quantity Decimal(12, 0)
/* 找进删除的进货单号给PurchaseID, 商品编号给ProductID, 数量给Quantity */
SELECT @PurchaseID = PurchaseID, @ProductID = ProductID, 
@Quantity = PurchaseQuantity
FROM deleted
/*找进这张进货单的进货属性*/
SELECT @PurchaseProperty = PurchaseProperty
FROM PurchaseMaster 
WHERE PurchaseID = @PurchaseID
/*计算库存量*/
IF @PurchaseProperty = '1' 
  /*进货:库存量减掉*/
  BEGIN
    UPDATE Product SET Quantity = Quantity - @Quantity 	                       
    WHERE ProductID = @ProductID
  END
ELSE	
  /*进货退出:库存量加回*/
  BEGIN
    UPDATE Product SET Quantity = Quantity + @Quantity
    WHERE ProductID = @ProductID
  END