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  • 1.  Activating CDC and use of logical logs

    Posted Fri August 11, 2023 05:35 PM

    Hello everybody,

    ¿Do you now if activating a table for CDC using the function cdc_set_fullrowlogging, use much more logical log ?  I have not found any reference in the documentation about it. 

    Please provide any clues according your experience.

    Regards,

    Roger



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    Roger Vilca
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  • 2.  RE: Activating CDC and use of logical logs

    Posted Sun August 13, 2023 07:54 AM

    Setting full row logging will increase logical log usage for updates and deletes primarily. Inserts will only be affected if you tend to insert partial rows.



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    Art S. Kagel, President and Principal Consultant
    ASK Database Management Corp.
    www.askdbmgt.com
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  • 3.  RE: Activating CDC and use of logical logs

    Posted Mon August 14, 2023 12:41 PM

    Only UPDATEs would be affected, and only if the table hadn't been using full row logging anyway, since e.g. containing varchars.

    The difference will be: instead of a single log record per UPDATE, logging only the differing bytes, two full images, before and after image of the row, would be logged - so the wider your table, the bigger typically the difference.

    No difference at all for INSERTs and DELETEs.



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    Andreas Legner
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