Re: Can we solve this -- NFNF and non-1NF at Loggerheads

From: David Cressey <david.cressey_at_earthlink.net>
Date: Mon, 07 Feb 2005 13:19:54 GMT
Message-ID: <_VJNd.3912$wK.2334@newsread3.news.atl.earthlink.net>

"Tom Ivar Helbekkmo" <tih+nr_at_eunetnorge.no> wrote in message news:86ekfskhw2.fsf_at_athene.hamartun.priv.no...
> "Alan" <not.me_at_rcn.com> writes:

> Of course, I fully agree with you that the moment we expand our
> relational model with operators that peek into attribute values,
> treating them as composite objects equivalent to rows, or even tables,
> we can no longer claim that tables containing such attributes satisfy
> the classic definition of 1NF. At this point, new definitions of the
> normal forms are needed, that take the new features into
> consideration.
>
> It seems intuitively obvious to me, though, that this can be done
> without breaking the underlying relational theory.

In the original Russel's paradox, the barber shaves every man in town, except those who shave themselves.

I understand you to be saying that an atomic value can be a relvar, provided that the relational engine is unaware that this is the case. Or am I misconstruing your remarks? Received on Mon Feb 07 2005 - 07:19:54 CST