Re: Grammatical Inconsistencies

From: Dawn M. Wolthuis <dwolt_at_tincat-group.com>
Date: Thu, 22 Apr 2004 14:50:46 -0500
Message-ID: <c697n2$fis$1_at_news.netins.net>


OK -- I thought all of these operations were on relations and returning relations.

Thanks for enlightening me EVEN THOUGH you said you would filter me out. Are you willing to bother showing me an example of the use of a join within the relational theory framework where it is not the same as the cross-product -- or pointing me to some such example? I suppose I'm pushing my luck, eh?
--dawn

Timothy J. Bruce" <uniblab_at_hotmail.com> wrote in message news:b4Vhc.1344$17.159553_at_news1.epix.net...
> [I'm going to hate myself in the morning for this...]
>
> The cartesian product of any number of sets defines a RELATION.
> The intersection, union, and symetric difference of any number of sets
> defines a SET.
>
> Patrick Suppes: ``Introduction to Logic'', Van Norstrand Company, Inc
> (August 1968)
> Ralph P. Grimaldi: ``Discrete and Combinatorial Mathematics'',
> Reading-Mass.: Addison-Wesley (1985)
> Larry J. Goldstein, David I. Schneider, Martha J. Siegel: ``Finite
> Mathematics And Its Applications'', Prentice-Hall, Inc (1995)
> Kolman, Bubsy, Ross: ``Discrete Mathematical Structures'', Prentice-Hall
> (2000)
> Donald E. Knuth: ``The Art of Computer Programming: Volume 1: Fundamental
> Algorithms (third edition)'', Addison-Wesley (1997)
> Donald E. Knuth: ``The Art of Computer Programming: Volume 3: Sorting and
> Searching (second edition)'', Addison-Wesley (1998)
>
> But what would Knuth know since he isn't a ``relational guy'',
> Timothy J. Bruce
> uniblab_at_hotmail.com
> </RANT>
>
>
Received on Thu Apr 22 2004 - 21:50:46 CEST

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