Home Forums SQL Server 2016 SQL Server 2016 - Development and T-SQL Performance improvement following a disable indexes, shrink, enable indexes - but why? RE: Performance improvement following a disable indexes, shrink, enable indexes - but why?

  • February 12, 2018 at 5:54 pm

    #1979550

    pcd_au - Monday, February 12, 2018 3:02 PM

    GilaMonster - Monday, February 12, 2018 2:13 AM

    Dropping and creating an index results in updated statistics (with FULLSCAN). that's the most common reason why index rebuilds improve performance.

    We tests Ola Hallengren's code against the database - nothing was found, everything check out OK.
    I'll give the update statistics with full scan a go.

    pcd

    That's not quite what she's saying.  She's was explaining that you disabling the indexes and then re-enabling them caused an index rebuild, which also causes a stats update with a full scan as a result.  It IS a good thing to use OLA's stuff to do your STATS updates on a regular basis whether or not an index needs defragmenting or not.

    --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.

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