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Elapsed time for data comparison?

I know that the hardware that Data Compare runs on would be a determining factor, but assuming a standard modern corporate laptop/desktop -- roughly how long would a comparison of two 12-14 terabyte databases take?

I suspect this is more in the timeframe of "days" rather than "hours", but is it closer to "days" or to "weeks"?

Has anyone tried something similar?


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    Eddie DEddie D Posts: 1,793 Rose Gold 5
    Hi OrangeData

    Thank you for your forum post.

    To be honest, I have no performance figures to advise upon. It will certainly take some time to complete. I suspect you experience Out of Memory errors or connection timeouts long before the data comparison completes.

    The comparison process will create temporary files on disk. The temporary files by default are created in the Windows temp directory. You can configure the RGTEMP system environment variable to work around this providing it is located on a different disk from the Windows OS and has sufficient free disk space for the creation of the temporary files for two 12-14 terabyte databases plus space for the deployment process.

    I recommend that you reduce the amount of data to be compared for each session, by reducing the number of tables to be compared by editing the project configuration -> Selecting the tables & views tab -> By default all tables that have an automatic comparison key are selected to be compared -> deselect table to remove from the comparison. Also make use of the WHERE clause filter, to filter the number of rows to be compare on each table selected for the comparison.

    This will mean making multiple comparisons and deployments, however it maybe more successful approach than performing one big huge comparison and deployment.

    Many Thanks
    Eddie Davis
    Senior Product Support Engineer
    Redgate Software Ltd
    Email: support@red-gate.com
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