Home Forums SQL Server 2008 SQL Server 2008 - General Commit, truncate of log file and checkpoint in SQL Server RE: Commit, truncate of log file and checkpoint in SQL Server

  • October 16, 2012 at 9:57 am

    #1549660

    Vegard Hagen (10/16/2012)

    For the record, I might add that a truncate log does not actually clear individual records or transactions from the log. It simply clears all VLFs (Virtual Log Files) that are currently marked as inactive.

    Truncating the log marks active VLFs that contain no log records needed by anything in the DB as inactive. There's no clearing that occurs, it's simply the marking of VLFs as inactive and hence reusable.

    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

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