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

In message <2bGxc.6816$n03.2311_at_newssvr32.news.prodigy.com>, Eric Kaun <ekaun_at_yahoo.com> writes
>"Tony" <andrewst_at_onetel.net.uk> wrote in message
>news:c0e3f26e.0406080151.2f2f3221_at_posting.google.com...
>> Where did you get that axiom from that "data comes in tuples"? Codd's
>> rule #1 says that all data in the database is to be REPRESENTED in
>> only one way: as values in attributes of tuples. It is a prescribed
>> RULE for building relational databases, it is not a claim that
>> anything in the real world "comes in tuples". We have a similar rule
>> in English that all objects are represented by words made up from the
>> 26 letters of the alphabet; it is not an "axiom" that says that
>> objects "come in" combinations of the letters A-Z.
>
>Ah, an excellent analogy. I'm sure it's flawed, but it gets the point across
>in a new way... thanks.

But in the reality we live in, all objects DO come in combinations of A-Z. So it has to be a theorem or an axiom. And if it's a theorem, from what axioms is it derived?
>
>> Your problem is that you consistently confuse data and reality.

I may well be confused. But that's because I'm actually trying to understand the link between the two. After all, isn't that the subject of this thread? And if there IS no link, what the hell's the point of studying data, since it is no use to us here in reality, anyway :-)
>>
>> Of course, this all doesn't mean that tuples are the BEST way to
>> represent data, or even that ALL data can be represented by tuples.
>
>Keep in mind that even if you say this, the orthogonal dimension is Type
>(Domain), which introduces wrinkles of its own.
>
>> But you could easily disprove a theorem that said that "all data can
>> be represented by tuples" by finding a counter-example. Bet you can't
>> though!
>
>Yes, good point - find us that black swan.
>
I'd suggest going to visit the Serpentine in Hyde Park :-) You'll find plenty there.

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
good idea to burden them with too much input. Hex always thought of his reports
as Lies-to-People.
The Science of Discworld : (c) Terry Pratchett 1999