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Message Posted: Mon, 02 Aug 2004 @ 20:30:33 GMT

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Hi Clay,

The physical design of the DBQL tables was aimed at efficiency of inserts, not ease of joining. "The odd choice of NUPIs" was intentionally selected so that entire blocks of data, all going to the same AMP, all with the same NUPI value (ProcID, CollectTimeStamp), could be quickly pushed into the database as a block, or several blocks. This is a contributing factor to there being virtually no overhead from DBQL logging for any all-AMP operation query.

The trade-off is, as has been pointed out, that's it more complicated to join across DBQL tables.

One alternative is to move the DBQL table data into your own database tables every 24 hours, doing whatever transformation or physical design changes you wish along the way.

Thanks, --Carrie

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