Re: History of 1NF

On Mar 12, 5:19 pm, Marshall <marshall.spi...@xxxxxxxxx> wrote:
Back in the day, Codd originally defined First Normal Form
(or maybe he was just calling it Normal Form back then)
and proved something about it. Something about an
isomorphism between nested relations and unnested
relations? Could someone state specifically what he
proved, please? And if anyone has a reference, that'd
be good too.

Thanks,

Marshall

I'm afraid I don't have links for you, but I doubt that anything was
strictly proven - Codd's initial publications were example driven (and
rightly so, given he was attempting to lead people out of a status quo
at the time). But also, has it not been shown that some boundary cases
do require nested relations to model? (but I'd need to hit the acm
portal to check that).

My intuition is (as in its a complete guess) that Codd, as a
mathematician, started with the notion of using relational theory, and
aware of the previous work on "conjunctive" and "disjunctive normal
forms", harnessed their conceptual basis and terminology to apply to
propositions. The clever sausage. Regards, J.

.

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