• Paul Randal (6/8/2010)


    Hugo Kornelis (6/8/2010)


    Good question, Paul!

    In your explanation, you write that log backups are about the same size as when full recovery had been uses. This matches my expectation, but in Books Online, it says:

    "The tradeoffs are bigger log backups and (...)"

    ms-help://MS.SQLCC.v9/MS.SQLSVR.v9.en/udb9/html/8cfea566-8f89-4581-b30d-c53f1f2c79eb.htm

    Is this a documentation bug?

    Hey Hugo - in the majority of cases I've seen, the log backups are a little smaller. I can easily think of cases where they'd be a bit larger (e.g. with a 5000-byte row, meaning 3000 bytes of wasted space per page being propagated into the backup - which wouldn't happen with regular logging. I would say that's a doc bug, yes.

    Thanks, Paul.

    I think the documentation writer meant to say that the log backups are bigger than the (active part of the) log file, but omitted to state that explicitly.

    I have submitted this as feedback to this BOL page.


    Hugo Kornelis, SQL Server/Data Platform MVP (2006-2016)
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