Re: Sixth normal form

From: David Cressey <>
Date: Tue, 21 Aug 2007 17:58:24 GMT
Message-ID: <4JFyi.3591$wr3.2580_at_trndny04>

"Brian Selzer" <> wrote in message news:9NDyi.28722$
> begin with. I never really came up with a clear definition of what it
> for a schema to have /at least as much/ information, nor did I provide any
> proof that if a relation is in 5NF, then the relationships between the
> dependent attributes are due to the fact that the relation is in 5NF, or
> that the presence of a pathological relationship between the dependent
> attributes indicates that the relation isn't in 5NF.

Part of the problem may be that the phrase "at least as much information" suggests some sort of measure of information, but not the information itself. For example, if you have "at least as much money in the bank as I have", it doesn't mean that you have the same money as I do in the bank.

I think what you may have meant might be better conveyed by a phrase like "at least all the same information as". But I'm not sure what you did mean, so this is just a guess. Received on Tue Aug 21 2007 - 19:58:24 CEST

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