Re: Multiple-Attribute Keys and 1NF

From: David Cressey <>
Date: Wed, 29 Aug 2007 05:23:57 GMT
Message-ID: <Np7Bi.1172$2p5.90_at_trndny05>

"JOG" <> wrote in message

> or perhaps I am doing the opposite and keeping 1NF and relaxing the
> use of finite partial functions to represent tuples. I find the
> definition of 1NF to be a pretty nebulous beast. The "NFNF" mob for
> example seem to produce relations with set-values which seem entirely
> in 1NF to me.

If you model your data using relations, and if you accept the proposition that all relations are inherently in 1NF, then the definition of 1NF becomes moot, for your purposes. Maybe that's why it's so nebulous.

I still work with the older definition of 1NF, and I model my data into SQL tables rather than relations. Given this starting place, the question "is the table under discussion in 1NF or not" is still a relevant one, and it has a clear answer. Nothing nebulous about it.

(At the conceptual level, I don't model my data into anything but attributes, with associated entities and relationships. That's a different discussion, and 1NF need not enter that discussion). Received on Wed Aug 29 2007 - 07:23:57 CEST

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