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From: Vadim Tropashko <vadimtro_invalid@yahoo.com>
Newsgroups: comp.databases.theory
Subject: Re: set builder notation for relational division
Date: 14 May 2007 10:39:33 -0700
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On May 13, 9:18 am, Marshall <marshall.spi...@gmail.com> wrote:
> If we want to generalize that, we could say
>
> A(a,b)
> B(b,c)
>
> A / B = {(a, c) | exists (a, b) in A forall (b, c) in B}

In domain calculus that would be:

 A(x,y) / B(y,z) = {(x, z) | for all y : (y, z) in B -> (x, y) in A}