Question

我有桌子A

FacilityID     CreatedDate       Active
---------------------------------------
   A001        2018-03-21          N
   A001        2018-03-22          Y
   A002        2018-03-21          Y

如果插入了A001或A002的新FacilityID，则旧记录应变为“N”。

我们可以通过After Insert触发器来实现这一目标吗？

格式化：

Create Trigger [dbo].[TableA_tr]
On [dbo].[Table A]
For INSERT
As
Begin
    Update [dbo].[Table A]
    Join 
    set [Active]='N'
    where [CreatedDate]<

Answer 1

USE AFTER INSERT触发器，因为您要插入新记录：

 Create trigger [dbo].[TableA_tr]
    on [dbo].[Table A]
    AFTER INSERT
    AS

    --Update all records with the same facility id that do not match the datetime of the new item
    UPDATE [dbo].[TableA]
    SET Active = 'N'
    FROM    inserted INS
    JOIN    dbo.TableA AS T
            ON  T.row_id = INS.row_id;
    WHERE T.[FacilityId] = INS.FacilityId AND T.[CreatedDate] <> INS.CreatedDate

    GO

Answer 2

这是另一种方法。这是基于设置的，如果您插入1或任意数量的行，它仍然可以正常工作。请记住，在每次操作时，sql server触发器触发一次，而不是像其他一些DBMS系统那样每行触发一次。

Create trigger [dbo].[TableA_tr]
    on [dbo].[Table A]
    AFTER INSERT
    AS

    --Update all records with the same facility id that do not match the datetime of the new item
    UPDATE a
    SET Active = 'N'
    from dbo.TableA a
    join inserted i on i.FacilityId = a.FacilityId
                and i.CreatedDate <> a.CreatedDate

将新记录插入表A时，将“活动”列更新为“N”

2 个答案: