Question

我需要帮助创建此触发器，任何帮助都会欣赏它，我无法保存此脚本，它说'无效列名OfferId'。但我检查了所有列的名称，它们是正确的

  CREATE TRIGGER dbo.OrderOffer_UpdatedUnits
  ON dbo.OrderOffer
  FOR  UPDATE
  AS

  BEGIN
  DECLARE @OfferId char(5)     SET  @OfferId = (Select OfferId From INSERTED i, OrderOffer a Where   i.OrderOfferid = a.OrderOfferid);
  DECLARE @UnitsAvailable int  SET  @UnitsAvailable = (Select SUM(UnitsAvailable) From dbo.Offer    Where OfferId=@OfferId);


  UPDATE dbo.OrderOffer SET dbo.UnitsAvailable = @UnitsAvailable
  FROM INSERTED i, OrderOffer a
  WHERE i.OrderOfferid = a.OrderOfferid 

 END

Answer 1

试试这个：

CREATE TRIGGER dbo.OrderOffer_UpdatedUnits
ON dbo.OrderOffer
FOR UPDATE
AS
BEGIN

    UPDATE a
    SET dbo.UnitsAvailable = 
        (
            Select SUM(b.UnitsAvailable) 
            From dbo.Offer b 
            Where b.OfferId = a.OfferId
        )
    FROM OrderOffer a
    INNER JOIN INSERTED i
    ON i.OrderOfferid = a.OrderOfferid

END

注意：我删除了变量，因为这会假设您一次只更新了一行。即使更新运行多行，上述内容仍然可以正常工作。

SQL触发器使用变量

1 个答案: