Home Forums SQL Server 2008 SQL Server 2008 - General “SELECT 1″ rather than a “SELECT *” when using an EXISTS or a NOT EXISTS clause”. RE: “SELECT 1? rather than a “SELECT *” when using an EXISTS or a NOT EXISTS clause”.

  • February 12, 2011 at 1:17 am

    #1285996

    luckysql.kinda (2/11/2011)

    Cost Analysis Among EXISTS (SELECT 1), EXISTS (SELECT COUNT(1)), EXISTS (SELECT *) AND EXISTS (SELECT TOP 1) should help

    Not really. Firstly there's no cost analysis there, no testing, no numbers, nothing other than the blogger's untested opinion, and one of the queries he lists is logically different from the others.

    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