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Use "Not in" or "Not exists"?

  • July 28, 2010 at 1:02 pm

    #221818

    I need to compare two tables. Data in the table of OrderHist always more than data in the table OrderCurrent.

    I used code below to compare:

    select ID from OrderHist h where not exists (select ID from OrderCurrent c where c.ID=h.ID)

    Can this code be improved?

  • July 28, 2010 at 1:09 pm

    #1199468

    Nope. That's about as good as it'll get. any tuning will depend on indexes.

    http://sqlinthewild.co.za/index.php/2010/02/18/not-exists-vs-not-in/

    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

    We walk in the dark places no others will enter
    We stand on the bridge and no one may pass

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