Home Forums SQL Server 2005 Administering IS (with nolock) is useful in (multiple join update) Query!! RE: IS (with nolock) is useful in (multiple join update) Query!!

  • Ivan Mohapatra (10/18/2012)


    if it is not useful then why ?

    1) Because it is ignored for the target of update statements (changes always have to take exclusive locks)

    2) Because it allows unpredictable, inconsistent results (missed rows, duplicated rows)

    3) Because using one of the snapshot isolation levels is almost always a better idea

    Gail Shaw
    Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
    SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability

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