Re: MV Keys

From: Jon Heggland <>
Date: Thu, 2 Mar 2006 14:10:53 +0100
Message-ID: <>

In article <>, says...
> To my current way of thinking, there are only the two compound types:
> list and set. There are certainly other ways of thinking, involving
> perhaps bags or whatever (or even objects :-). And note that those
> two are not minimal, insofar as lists can be implemented quite
> soundly (but not conveniently) with sets, and sets can be
> implemented quite conveniently (but not soundly) with lists.

So it is essentially an arbitrary decision? Why make it, then?

> This is why I predict that, if we were given NFNF as an
> option, we'd find that the sweet spot would be close to,
> but not right at, fully 1NF. (Assuming availability of
> join. If you don't have join, you can't easily recompose
> decomposed relations.)

This is exactly what Date has said for a long time, in his work on RVAs.

Received on Thu Mar 02 2006 - 14:10:53 CET

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