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Re: How to find Brothers and Sisters?

From: Cimode <cimode_at_hotmail.com>
Date: 4 Dec 2006 07:55:11 -0800
Message-ID: <1165247711.670573.220910@16g2000cwy.googlegroups.com>

David Cressey a écrit :

> "Cimode" <cimode_at_hotmail.com> wrote in message
> news:1165242357.899497.161570_at_j44g2000cwa.googlegroups.com...
>
> >> I would think this is more a design flaw than the table not formally
> >> being in 1NF. No repeating groups. check. Data in the form of a
> >> relation. check. Some root entry in 'persons' who has himself or one of
> >> his successors as a father... erm.....hold on...
> >>
> >> (I think that Marshall once pointed out that the technical term for
> >> this is Furturama-NF, where Fry is his own grandfather)
> > Repeating groups is not the only prerequisite to state a table is in or
> > is not in 1NF.
>
> > There is no way you can be in 1NF if NULL values are permitted OR if
> > you have 2 different predicates in the same RTable...Only one predicate
> > per RTable.. That's by definition. Period.
>
>
> Where did you get that definition?

Check...
06/03 #2: WHAT FIRST NORMAL FORM MEANS NOT by F. Pascal (Updated 03/04) 06/03 #1: WHAT FIRST NORMAL FORM REALLY MEANS by C. J. Date Received on Mon Dec 04 2006 - 09:55:11 CST

Original text of this message

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