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Re: ISSUE-20: SPARQL Update: Empty vs non-existent graphs

From: Andy Seaborne <andy.seaborne@talis.com>
Date: Fri, 08 Jan 2010 09:58:20 +0000
Message-ID: <4B4701BC.5090900@talis.com>
To: Paul Gearon <gearon@ieee.org>
CC: SPARQL Working Group <public-rdf-dawg@w3.org>


On 07/01/2010 9:06 PM, Paul Gearon wrote:
> On Wed, Dec 23, 2009 at 6:33 AM, Andy Seaborne<andy.seaborne@talis.com>  wrote:
>> ISSUE-20
    ...
>> It can show up in query in
>>    SELECT * { GRAPH ?g {...} }
>
> Just to be clear, we expect:
>
>    SELECT ?g { GRAPH ?g { ?s ?p ?o } }
>
> to only return graphs with something in them, right? I suppose this
> means there's no standard way to query for the existence of an empty
> graph.

The simplest would be:

SELECT ?g { GRAPH ?g { } }

	Andy
Received on Friday, 8 January 2010 09:58:43 GMT

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