Re: Complete axiomatization of relational algebra

Relational algebra as I understand it is equivalent to first-order logic (i.e. there is a transformation - in both directions - which preserves validity).
Since the set of valid first-order sentences is recursively enumerable, the same applies to relational algebra.

But I presume your question is:
Is there a finite axiom system for relational algebra?

I do not know an answer to this,
but I remember the corresponding question was open for the algebra of BINARY relations.
And it was answered negatively,
i.e. they is no finite equational axiom system.

Jan Hidders schrieb:
>
> Does anybody know if there is a complete algebraic axiomatization of the
> relational algebra (as used in relational database theory) or a proof
> that such a thing is not possible?
>
> --
> Jan Hidders
 

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Prof. Dr. Wolfgang Schoenfeld, GMD-IPSI, +49-6151-869-865