Re: Database design
Date: 21 Feb 2006 19:01:29 -0800
Message-ID: <1140577289.242937.304950_at_g44g2000cwa.googlegroups.com>
Gene Wirchenko wrote:
> On Tue, 21 Feb 2006 18:14:12 -0800, Mark Johnson
> <102334.12_at_compuserve.com> wrote:
>
> >"JOG" <jog_at_cs.nott.ac.uk> wrote:
> >
> >>This whole 'flat' debate is nonsense too. Write a database down in its
> >>mathematical form, devoid of tables
> >
> >It is flat. A relation has no structure, unless there is some ordering
> >among the attributes. The attributes are supposed to be in no
> >particular order. The entries/instances/tuples are supposed to be in
> >no particular order. That's just definitional.
>
> It is n-dimensional, one dimension per attribute. The three
> dimensions of Euclidean space are not in any particular order either.
Wol & JOG had an exchange about "dimension" in the comments at the end
of
http://www.tincat-group.com/mewsings/2006/02/model-behind-interface.html
where I contributed the following:
"The word dimension is overloaded, so JOG is right that using the mathematical definition, an n-tuple is n-dimensional. Using a more typical physical definition or a programming language Array definition of dimension as Wol has done, it would make sense to call such tables 2D, given that each value can be accessed with its [i][j]. This misunderstanding crops up all the time, and I fault those with the mathematical definition...for this one because I think they really do understand the alternative use of the term, while the programmers don't always know the mathematical definition. There, have I settled that one for all time?"
I suspect the answer is "of course not." Cheers! --dawn Received on Wed Feb 22 2006 - 04:01:29 CET