Home Forums SQL Server 2008 T-SQL (SS2K8) How do i update an identity column with identity value? RE: How do i update an identity column with identity value?

  • CREATE TABLE #Table

    (

    ID INT IDENTITY

    ,x INT

    );

    SET IDENTITY_INSERT #Table ON;

    INSERT INTO #Table (ID, x)

    SELECT 0, 0 UNION ALL SELECT 0, 0;

    SELECT *

    FROM #Table;

    -- You can't do this

    WITH a AS

    (

    SELECT ID, n=ROW_NUMBER() OVER (ORDER BY (SELECT NULL))

    FROM #Table

    WHERE ID = 0

    )

    UPDATE a

    SET ID = n;

    GO

    -- But you can try this

    DBCC CHECKIDENT (#Table, RESEED, 0);

    SET IDENTITY_INSERT #Table OFF;

    INSERT INTO #Table (x)

    SELECT x

    FROM #Table;

    DELETE FROM #Table

    WHERE ID = 0;

    SELECT *

    FROM #Table;

    SET IDENTITY_INSERT #Table OFF;

    GO

    DROP TABLE #Table;


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    [url url=http://www.sqlservercentral.com/articles/St