Home Forums SQL Server 2012 SQL 2012 - General Creating index on multiple columns separately or should be avoided to gain performance for add/update and select cases RE: Creating index on multiple columns separately or should be avoided to gain performance for add/update and select cases

  • July 28, 2015 at 10:43 am

    #1815495

    And remember, the order of the keys on the indexes matters quite a bit, especially for the first column since that determines what is in the histogram of the statistics. This means in a case where you have ID1 & ID2 in one index, ID2 & ID1 in a different index may work better for some queries, differently than the first index. As Gail says, testing is the only way to be sure.

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