Re: In an RDBMS, what does "Data" mean?

In message <lgGxc.6818$eP2.1437_at_newssvr32.news.prodigy.com>, Eric Kaun <ekaun_at_yahoo.com> writes
>"Anthony W. Youngman" <wol_at_thewolery.demon.co.uk> wrote in message
>news:g2TfG9KDCPxAFwFH_at_thewolery.demon.co.uk...
>> In message <9X%vc.5730$tB.3511_at_newssvr32.news.prodigy.com>, Eric Kaun
>> <ekaun_at_yahoo.com> writes
>> >Perhaps, but I still don't think "data comes in tuples" is anything like
>an
>> >axiom. I could certainly be wrong.
>>
>> Read C&D's first rule! "Data comes in rows" - which is as far as I can
>> make out, a synonym for "data comes in tuples". I'm sure a relational
>> guru will disagree, but I can't see the difference ...
>
>And as stated elsewhere, those aren't axioms anyway... he used the word
>"representation", and the context fully suggests that he's not correlating
>it with the real world.
>
I know. After writing that I thought rather more about what C&D's twelve rules actually are. And that they don't seem to contain any axioms at all.

Which leads to the conclusion that relational theory is axiom-free. Which means that it cannot be a valid model. Which means that its application to the real world has no basis in anything whatsoever.

Okay, I'm sure that the mathematicians who've built on it have fleshed out the fundamentals somewhat, but it certainly means that if your sole criteria for defining a "relational database" is that "it complies with C&D's 12 rules", then such a database has no grounding in formal logic whatsoever.

Cheers,
Wol

-- 
Anthony W. Youngman - wol at thewolery dot demon dot co dot uk
HEX wondered how much he should tell the Wizards. He felt it would not be a
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