Re: How to find Brothers and Sisters?
Date: 4 Dec 2006 07:55:11 -0800
Message-ID: <1165247711.670573.220910_at_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...