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Re: Order of evaluation for aggregates

From: Andy Seaborne <andy.seaborne@epimorphics.com>
Date: Mon, 21 Nov 2011 14:36:06 +0000
Message-ID: <4ECA61D6.6030408@epimorphics.com>
To: public-rdf-dawg@w3.org


On 15/11/11 19:22, Birte Glimm wrote:
...

> But while we are at it, there is a lowercase extend in the Definition of Extend:
> Extend(Ω , var, term) = { extend(μ, var, term) | μ in Ω }

Corrected.

>
> It is also lowercase in the evaluation semantics:
> Definition: Evaluation of Extend
> eval(D(G), extend(var, expr, P)) = extend(var, expr , eval(D(G), P))

Corrected.

> Furthermore, here we swap the order. It should be
> eval(D(G), Extend(P, var, expr)) = Extend(eval(D(G), P), var, expr)
> or the algorithm for translating queries into the algrebra is wrong
> and has to be changed.

Corrected.

Thanks

	Andy

>
> Birte
>>         Andy
>>
>
>
>
Received on Monday, 21 November 2011 14:36:39 GMT

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