Home Forums SQL Server 2012 SQL Server 2012 - T-SQL How to quickly update/insert 3M records in a large table? RE: How to quickly update/insert 3M records in a large table?

  • March 30, 2015 at 10:28 am

    #1787417

    Jason-299789 (3/30/2015)

    I would also suggest that the key on both the destination table is clustered it should make the process significantly faster. so something like.

    "It Depends". Unless the key is ever increasing, Inserts could suffer dramatically due to page splits no matter how they are accomplished.

    And I'm not so sure that MERGE will provide anything substantial in the area of performance. To be honest, I'm also not sure that it won't, so it's worth a try even if my hypothesis is that it won't. I don't use MERGE in SQL Server because there have been way too many reported problems with it and I can tolerate doing "l' fashioned", yet effective "upserts" until that the reported problems seriously decline.

    --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)