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Re: Lots of Idiotic Silly Braces?

From: paul c <toledobythesea_at_oohay.ac>
Date: Fri, 20 Jul 2007 22:23:20 GMT
Message-ID: <sBaoi.133437$NV3.45875@pd7urf2no>


Brian Selzer wrote:
> ... Lending support to this is the fact that the duality of GROUP and
> UNGROUP does not hold for R. r UNGROUP S yields the relation value (call it
> r'), ...

Just an aside, regarding "duality", I sometimes think that it could be possible, if values were always sets of values, to avoid UNGROUP entirely and its distortion of certain single attribute relations. Projection might even be a special case of a GROUP that operated on sets. But this is just my peculiar view that conventional experts are likely to call twisted if not wacky.

p Received on Fri Jul 20 2007 - 17:23:20 CDT

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