而不是SQL Server中的触发器会丢失SCOPE_IDENTITY? [英] Instead of trigger in SQL Server loses SCOPE_IDENTITY?

问题描述

我有一个表，在其中创建了INSTEAD OF触发器以执行一些业务规则.

I have a table where I created an INSTEAD OF trigger to enforce some business rules.

问题在于，当我向该表中插入数据时，SCOPE_IDENTITY()返回一个NULL值，而不是实际插入的身份.

The issue is that when I insert data into this table, SCOPE_IDENTITY() returns a NULL value, rather than the actual inserted identity.

INSERT INTO [dbo].[Payment]([DateFrom], [DateTo], [CustomerId], [AdminId])
VALUES ('2009-01-20', '2009-01-31', 6, 1)

SELECT SCOPE_IDENTITY()

触发:

CREATE TRIGGER [dbo].[TR_Payments_Insert]
   ON  [dbo].[Payment]
   INSTEAD OF INSERT
AS 
BEGIN
-- SET NOCOUNT ON added to prevent extra result sets from
    -- interfering with SELECT statements.
    SET NOCOUNT ON;

    IF NOT EXISTS(SELECT 1 FROM dbo.Payment p
              INNER JOIN Inserted i ON p.CustomerId = i.CustomerId
              WHERE (i.DateFrom >= p.DateFrom AND i.DateFrom <= p.DateTo) OR (i.DateTo >= p.DateFrom AND i.DateTo <= p.DateTo)
              ) AND NOT EXISTS (SELECT 1 FROM Inserted p
              INNER JOIN Inserted i ON p.CustomerId = i.CustomerId
              WHERE  (i.DateFrom <> p.DateFrom AND i.DateTo <> p.DateTo) AND 
              ((i.DateFrom >= p.DateFrom AND i.DateFrom <= p.DateTo) OR (i.DateTo >= p.DateFrom AND i.DateTo <= p.DateTo))
              )

    BEGIN
        INSERT INTO dbo.Payment (DateFrom, DateTo, CustomerId, AdminId)
        SELECT DateFrom, DateTo, CustomerId, AdminId
        FROM Inserted
    END
    ELSE
    BEGIN
            ROLLBACK TRANSACTION
    END


END

该代码在创建此触发器之前已经起作用.我在C#中使用LINQ to SQL.我看不到将SCOPE_IDENTITY更改为@@IDENTITY的方法.我该如何进行这项工作?

The code worked before the creation of this trigger. I am using LINQ to SQL in C#. I don't see a way of changing SCOPE_IDENTITY to @@IDENTITY. How do I make this work?

推荐答案

使用@@identity代替scope_identity().

scope_identity()返回当前作用域中最后一个创建的ID，而@@identity返回当前会话中最后一个创建的ID.

While scope_identity() returns the last created id in the current scope, @@identity returns the last created id in the current session.

通常建议在@@identity字段上使用scope_identity()函数，因为您通常不希望触发器干扰id，但是在这种情况下，您可以这样做.

The scope_identity() function is normally recommended over the @@identity field, as you usually don't want triggers to interfer with the id, but in this case you do.

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