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how to optimize this query

  • December 22, 2004 at 2:18 pm

    #109351

    INSERT INTO SELECT * FROM data (NOLOCK) WHERE DATEDIFF(hh,()) > 64

    Thanks for your help

  • December 22, 2004 at 6:03 pm

    #534841

    You should get a performance improvement if you take the dynamic getdate() out of the queries ...

    declare @now datetime

    set @now = getdate()

    INSERT INTO monitordata

    SELECT * FROM data (NOLOCK) WHERE DATEDIFF(hh,time_stamp,@now) > 6

    DELETE data WHERE DATEDIFF(hh,time_stamp, @now) > 6

    This will also ensure that exactly the same resultsets are returned for both the INSERT and the DELETE queries.

    The absence of evidence is not evidence of absence.
    Martin Rees

    You can lead a horse to water, but a pencil must be lead.
    Stan Laurel

  • December 22, 2004 at 9:43 pm

    #534847

    thanks for your input

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