Home Forums SQL Server 2008 SQL Server Newbies Check Data exists or not RE: Check Data exists or not

  • November 30, 2013 at 11:13 pm

    #1669938

    kapil_kk (11/30/2013)

    can you please tell me how merge doesn't process row by row...

    Actually, everything in SQL Server processes "row by row". If you let SQL Server do it, it's fast. If you try to tell SQL Server how to do it, it's slow. If you look at SELECT, INSERT, UPDATE, DELETE, or MERGE, do you see anything in there that would allow you to control the looping in the background?

    MERGE is no different than the 4 other basic statements when it comes to processing.

    --Jeff Moden

    RBAR is pronounced "ree-bar" and is a "Modenism" for Row-By-Agonizing-Row.
    First step towards the paradigm shift of writing Set Based code:
    ________Stop thinking about what you want to do to a ROW... think, instead, of what you want to do to a COLUMN.

    Change is inevitable... Change for the better is not.

    Helpful Links:
    How to post code problems
    How to Post Performance Problems
    Create a Tally Function (fnTally)