Re: infinite result sets?

graeme_at_inorbit.com (Graeme Newlands) wrote in message news:<aecd37bf.0402140841.49e8a115_at_posting.google.com>...
> Just a random thought over the weekend ...
>
> Is there any join operation that could possibly return an infinite
> result set in set theory?
>
> Is this operation definable in SQL?
>
> Graeme Newlands.

Hello Graeme,

Still thinking nice abstruse thoughts then :)

In set theory, yes, why not ? The set of all real numbers is a set, so...

In relational theory though, I'm not sure whether these kind of relations are expressible. Relational calculus could probably describe an infinite relation, but I'm not sure about the algebra. Maybe some of the papers on the Unversal Relation might have some pointers.

SQL is a no-no for this kind of "interesting" question; it has it's own set of "interesting" questions instead...

• Tony