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Re: Normalisation

From: Paul <paul_at_test.com>
Date: Mon, 04 Jul 2005 23:19:32 +0100
Message-ID: <42c9b5f4$0$41899$ed2619ec@ptn-nntp-reader03.plus.net>


paul c wrote:
> the protocol would be needed most obviously so that the RM would know in
> what form, for example what bit configuration, to store values or
> present them to the party that does understand those values in a way
> that doesn't undercut consistent behaviour in the future. i'd say this
> means that the RM cannot itself even decide equality. it should
> theoretically always have to inquire of some outside party whether two
> values are 'equal'. (if there is any respected definition of the RM
> that does claim to define equality, i'd like to see it.)

I guess the problem is that a single value in a domain may have multiple representations. For example in a domain of rational numbers: 1/2 = 2/4 = 3/6 = 4/8 = ...

And the relational model couldn't possibly know these are equal, because arithmetic is outside its area of knowledge.

Unless domains had to store equivalent values in some canonical form I suppose? So there was always a 1-1 mapping between values and representations.

Paul. Received on Mon Jul 04 2005 - 17:19:32 CDT

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