如何在事务中获取Identity列值(尚未提交)

Question

在TSQL事务中,我有一个操作,即将记录插入到a MyTable1和更新a的操作中,该操作MyTable2使用记录的Identity列值进行更新MyTable1,该操作仅在提交事务后插入.
那么,如何在实际插入表之前获取这个自动生成的值？

代码只是为了说明问题:

CREATE TABLE MyTable1(
MyTable1Id int identity(1,1) primary key,
Field1 varchar(50)
) 

CREATE TABLE MyTable2(
MyTable2Id int identity(1,1) primary key,
MyTable1Id int
)


CREATE PROCEDURE MyProc(
   @MyVal1  [varchar](50)
)
AS
BEGIN TRAN
-- try to insert
INSERT INTO MyTable1(
   Field1
)
SELECT @MyVal1

IF @@ERROR <> 0
BEGIN
  ROLLBACK TRAN
END

-- update MyTable2
DECLARE @TheUnknownIdValue int
UPDATE MyTable2
SET    MyTable1Id = @TheUnknownIdValue -- how to get the value needed here?
WHERE ...

IF @@ERROR <> 0
BEGIN
  ROLLBACK TRAN
END

COMMIT TRAN 

Answer 1

在使用SCOPE_IDENTITY() 之后使用INSERT

--
DECLARE @newId INT 
INSERT INTO MyTable1(
   Field1
)
SELECT @MyVal1
--End of Insert here
SELECT @newId = SCOPE_IDENTITY()
--Rest of the procedure