W3C home > Mailing lists > Public > public-sparql-dev@w3.org > July to September 2013

Re: Querying Named Graph using SPARQL

From: Rob Vesse <rav08r@ecs.soton.ac.uk>
Date: Tue, 13 Aug 2013 11:24:37 -0700
To: David Booth <david@dbooth.org>, Axel Polleres <axel@polleres.net>
CC: Quentin Reul <Quentin.H.Reul@gmail.com>, <semantic-web@w3.org>, <public-rdf-wg@w3.org>, <public-sparql-dev@w3.org>
Message-ID: <EMEW3|349a91e7d3dea618cfb598661c24df71p7CJP106rav08r|ecs.soton.ac.uk|CE2FC792.270B0%rav08r@ecs.soton.ac.uk>
The spec is correct.  The query Axel gave should produce a list of named
graphs in the dataset.

If an implementation does not interpret this query correctly this is an
implementation bug and people should file bug reports through the
appropriate channels for the implementation(s) in question.

Rob

On 8/13/13 11:21 AM, "David Booth" <david@dbooth.org> wrote:

>Hi Axel,
>
>That doesn't work in Sesame 2.7.1 at least, apparently because ?G is not
>bound, even though there is one solution.  The SPARQL 1.1 spec says:
>http://www.w3.org/TR/sparql11-query/#emptyGroupPattern
>[[
>The group pattern:
>   { }
>matches any graph (including the empty graph) with one solution that
>does not bind any variables.
>]]
>
>Is this a bug in the spec?
>
>David
>
>On 08/13/2013 11:48 AM, Axel Polleres wrote:
>> Hi Quentin,
>>
>> how about just
>>
>>   SELECT ?G WHERE { GRAPH ?G {} }
>>
>> (no need to dump all triples, if the only concern is which ?G exist)
>>
>> BTW, public-sparql-dev@w3.org may be the list you wanted to use.
>>
>> best,
>> Axel
>>
>
Received on Tuesday, 13 August 2013 18:25:30 UTC

This archive was generated by hypermail 2.3.1 : Tuesday, 6 January 2015 20:15:52 UTC