Re: SQL For Smarties 3rd Edition - ATTN Joe Celko

From: Lemming <thiswillbounce_at_bumblbee.demon.co.uk>
Date: Tue, 12 Dec 2006 02:06:28 +0000
Message-ID: <qe3sn2l2pv8rkge67bocs2g0o3i6ioemjf_at_4ax.com>


On 15 Nov 2006 19:38:36 -0800, michael_at_preece.net wrote:

>
>Pickie wrote:
>> Jan Hidders wrote:
>> > David Cressey wrote:
>> > >
>> > > Here's the link to the top level page....
>> > >
>> > > http://www.utexas.edu/its/windows/database/datamodeling/rm/overview.html
>> > >
>> > > This leads down to E-R modeling, and introduces tables, etc. and also
>> > > normalization.
>> >
>> > Indeed a very nice reference. But ... I'm not very happy with their
>> > definitions of the normal forms.
>> <rest snipped>
>>
>> I'm surprised there wasn't a howl of outrage at this!
>>
>> "The relational model represents data in the form of two-dimension
>> tables. Each table represents some real-world person, place, thing, or
>> event about which information is collected. A relational database is a
>> collection of two-dimensional tables."
>
>I think the author must be confused and thinking of "columns" as one
>dimension and "rows" as the other. I used to make that mistake myself
>too. It's easily done. The mistake I, and perhaps the author, made was
>that we saw a "row" representing what I might call a record, but failed
>to immediately see that it also represents an n-dimensional tuple.
>Guffaw!

D'Oh! What an ass. Of course, he failed to see that the rows are the one dimension, and columns are the other. Tsk!

/me scratches head.

Hint: in the real world, we make a living by understanding that it doesn't matter all that much how you conceptualise data; it's just data. In 99.9% of cases, as long as you can process it, the client is happy.

Lemming

-- 
Curiosity *may* have killed Schrodinger's cat.
Received on Tue Dec 12 2006 - 03:06:28 CET

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