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Re: c.d.theory glossary - RELATION

From: Dan <guntermannxxx_at_verizon.com>
Date: Tue, 27 Apr 2004 03:34:10 GMT
Message-ID: <Swkjc.40985$Aq.18000@nwrddc03.gnilink.net>

"Laconic2" <laconic2_at_comcast.net> wrote in message news:ROGdnQMV7tlYiRDdRVn_iw_at_comcast.com...
> Sound like the right definition to me.
>
> Everyone should note, in passing, that there is nothing in the above
> definition to forbid one of the constituent sets, Sx from
> itself being a relation. But maybe I shouldn't open that can of worms
> again.
>

Perhaps something else worth explicitly mentioning is that a set, Sx, is not restricted from participating as a member of a relation more than once. Distinction between identical sets in math is possible through ordinal numbering such that given sets Sx and Sy, x <> y AND Sx is a subset of Sy and Sy is a subset of Sx; in relational theory, in contrast, it is by attribute name.

Regards,

Received on Mon Apr 26 2004 - 22:34:10 CDT

Original text of this message

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