Question

我有一个表tblDHColl，其中包含ProjectID，HoleID，X，Y，Z和Locked（位数据类型）字段。我想创建一个触发器来阻止任何更新或删除Locked = 1或＆＃39; True＆＃39;的洞。如果Locked字段为0或“false”，则我希望允许对数据进行任何其他更新或删除操作。任何洞。由于我是触发器的新手，请告诉我如何在tblDHColl上创建触发器。

CREATE TRIGGER [dbo].[TR_utblDHCollRollBack] ON [dbo].[tblDHColl] 
FOR UPDATE, DELETE 
AS 
    IF EXISTS
    (
        SELECT * 
        FROM deleted d 
        INNER JOIN tbldhcoll c ON d.DataSet = c.DataSet AND d.Hole_ID = c.Hole_ID 
        where locked=1
    ) AND EXISTS
    (
        SELECT * 
        FROM inserted i 
        INNER JOIN tbldhcoll c ON i.DataSet = c.DataSet AND i.Hole_ID = c.Hole_ID 
        where locked=1
    ) 
    BEGIN 
        RAISERROR('ERROR: Validated data cannot be modified',16,-1) 
        ROLLBACK TRANSACTION 
        RETURN 
    END 
GO 

ALTER TABLE [dbo].[tblDHColl] ENABLE TRIGGER [TR_utblDHCollRollBack] GO

亲切的问候，迪内希

Answer 1

如果要更改删除或更新记录的逻辑，则应使用“代替”触发器。它会是这样的：

CREATE TRIGGER [dbo].[TR_utblDHCollRollBack] ON [dbo].[tblDHColl] 
INSTEAD OF UPDATE, DELETE 
AS 
    IF TRIGGER_NESTLEVEL() > 1 RETURN

    DECLARE @Count  INT
    SELECT @Count = COUNT(*) FROM inserted

    IF @Count > 0 -- This is UPDATE

    BEGIN   

        UPDATE c
        SET
        Field1 = i.Field1,
        Field2 = i.Field2,
        /*
        .
        .
        .
        */
        FieldN = i.FieldN
        FROM deleted d 
        INNER JOIN inserted i ON i.Hole_ID = d.Hole_ID
        INNER JOIN tbldhcoll c ON d.DataSet = c.DataSet AND d.Hole_ID = c.Hole_ID 
        where ISNULL(d.locked, 0) != 1
    END

    ELSE 

    BEGIN   

        DELETE c        
        FROM deleted d 
        INNER JOIN tbldhcoll c ON d.DataSet = c.DataSet AND d.Hole_ID = c.Hole_ID 
        where ISNULL(d.locked, 0) != 1

    END
GO

触发不更新和删除数据

1 个答案: