Re: A Normalization Question

"Dan" <guntermannxxx_at_verizon.com> wrote in message news:YDmHc.40521$qw1.28576_at_nwrddc01.gnilink.net...
>
> "Alan" <alan_at_erols.com> wrote in message
> news:2l2btjF813i3U1_at_uni-berlin.de...
> >
> > "Neo" <neo55592_at_hotmail.com> wrote in message
> > news:4b45d3ad.0407061849.580874d6_at_posting.google.com...
> > > > Yes, [RM] has limitations, but normalizing data is not one of them.
> > > > The RM defines normalization.
> > >
> > > RM defines a limited form of normalization. The general form of
> > > normalization which is the central theme to all xNFs (where x may be
> > > infinite), allows one to identify 'brown', 'brown', 'brown' as being
> > > redundant which XDb1/TDM normalizes.
> > >
> > > > You just refuse to accept normalization ...
> > >
> > > I accept the general form of normalization that can be applied to all
> > > data models and allows one to recognize that 'brown', 'brown', 'brown'
> > > is redundant. I refuse to accept RM's limited form of normalization as
> > > the general form of normalization which doesn't allow one to recognize
> > > that 'brown', 'brown', 'brown' is redundant.\
> >
> > It's not, it's not, it's not. You can preach this nonsense till the cows
> > come home, but it will never be true. Several examples have been
provided
> to
> > you.
> >
> > >
> > > > > A better reference is C.J. Date's "An Intro to Database
Systems"...
> > > >
> > > > How does that make it better?
> > > > Anyways how would you know it is better since you never read
Navathe?
> > >
> > > While I have not read all 873 pages of Elmasri/Navathe's "Fund of Db
> > > Sys" 2nd Ed that sits several books under my C.J. Date's "Intro to Db
> > > Sys" 6th Ed, I have read enough of it to know that compared to that of
> > > Date's p288-9, their fundamental explanation of normalization on p407
> > > is limited: "Normalization of data can be looked on as a process
> > > during which unsatisfactory relation shemas are decomposed by breaking
> > > up their attributes into smaller relations schemas that possess
> > > desirable properties". C.J. Date's is better because his fundamental
> > > explanation comes closer to the general form of normalization that can
> > > be applied to data in any model, even those that don't have any
> > > relations.
> >
> > That's on old version, maybe 12 years old. They are up to 4th Ed. now.
> >
> > Anyway, As I stated elswhere, I give up.
> >
> >
> Don't give up!
>
> I see this discussion as very beneficial to the entire group, or at least
> for me. It forces everyone to revisit the fundementals and re-examine our
> own understanding of them.
>
> Actually, if Neo's ideas were practical at the physical level and he never
> introduced his form of "normalization" to the logical user level as a form
> of data model, I wouldn't have an issue with his "implementation" at all
as
> long as it behaved functionally as a user would expect -- operations and
> inference rules over semantics units.
>
> - Dan
>
>

Unfortunately, I don't agree that his implemenation is practical. You wind up storing nothing but pointers to data. This would be a nightmare when it comes time to extract the data. Imagine trying to debug a report. Then there is the question of data entry. How would the system know what data was already entered? Ex: A user goes to enter the string "Brown" as a car color. The system would need to check to see if that string was already enetered. The overhead would be enormous. Received on Fri Jul 09 2004 - 14:07:16 CEST