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Re: meaning of GRAPH ?g {}

From: Rob Vesse <rav08r@ecs.soton.ac.uk>
Date: Tue, 30 Jul 2013 13:22:25 -0700
To: <public-sparql-dev@w3.org>
Message-ID: <EMEW3|0ea0d4391a4eeec170fd89a182a30632p6YLMc06rav08r|ecs.soton.ac.uk|CE1D6DF2.2617F%rav08r@ecs.soton.ac.uk>
Strictly speaking I believe that yes you should get back <aa> and <bb>

{} always matches - it returns a multiset with a single empty row thus
since GRAPH is defined as being the UNION over applying the graph pattern
over each named graph you should get a single row with ?g bound for each
named graph in the store.

This is likely a triple store defect

Rob

On 7/30/13 1:00 PM, "Jeremy J Carroll" <jjc@syapse.com> wrote:

>
>If I have a dataset
>
><aa> { <sa> <pa> <oa> }
>
><bb> { <sb> <pb> <ob> }
>
>And ask
>
>SELECT ?g
>{ GRAPH ?g {}
>}
>
>what should I get back.
>I thought it should be <aa> and <bb> but to get that I had to rewrite the
>query as
>
>SELECT DISTINCT ?g
>{ GRAPH ?g { ?s ?p ?o}
>}
>
>Should I report this as a triple store defect?
>
>
>
>Jeremy J Carroll
>Principal Architect
>Syapse, Inc.
>
>
>
>
Received on Tuesday, 30 July 2013 20:23:05 UTC

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