Question

我从SqlServer 2000中的以下触发器开始

 ALTER TRIGGER DeleteTrigger
 ON [dbo].[WarrantyClaimsLineItems]
 FOR DELETE
 AS 
 begin

    declare @wa int
    SET @wa = (SELECT warrantyAuthNo from DELETED)
    update dbo.warrantyclaimsauth
    set isused = 0
    WHERE warrantyClaimsAuth.warrantyauthno = @wa


end

基本上，只要从表中删除订单项，我就需要将分配给该订单项的warrantyauth.isUsed更新回false。

删除一个订单项时有效，但删除多个订单项时出现以下错误。

Subquery returned more than 1 value. This is not permitted when the subquery follows =, !=, <, <= , >, >= or when the subquery is used as an expression.

我明白为什么，触发器只能删除一条记录。所以我需要修改它来处理多行删除。

我做了一些研究并修改了我的触发器

....
 AFTER DELETE
 AS 
 begin

    update dbo.warrantyclaimsauth set isUsed = 0
    from dbo.warrantyclaimsauth a
    inner join deleted d on a.warrantyAuthNo = a.warrantyAuthNo


 end

然而，这是在isUsed字段中将powersyclaimsauth中的每一行更新为0。任何人都可以帮我解决我做错的事吗？谢谢！

Answer 1

第二个连接条件错误。试试这个：

 AFTER DELETE
 AS 
 begin

    update a set isUsed = 0
    from dbo.warrantyclaimsauth a
    inner join deleted d on a.warrantyAuthNo = d.warrantyAuthNo


 end

您加入的deleted warrantyauthno等于自己，而不是deleted表中的值。您基本上只是cross join deleted而不是过滤任何行。

Answer 2

inner join deleted d on a.warrantyAuthNo = a.warrantyAuthNo

应该是

inner join deleted d on a.warrantyAuthNo = d.warrantyAuthNo

您目前有一个简单的连接条件，它提供的交叉连接不会过滤到deleted

Answer 3

....
 AFTER DELETE
 AS 
 begin

    update dbo.warrantyclaimsauth set isUsed = 0
    from dbo.warrantyclaimsauth a
    inner join deleted d on a.warrantyAuthNo = d.warrantyAuthNo


 end

删除多个行的删除触发器中的表更新

3 个答案: