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Re: Finding a SPARQL endpoint by an LOD URI?

From: Keith Alexander <keithalexander@keithalexander.co.uk>
Date: Wed, 4 Jul 2012 08:13:39 +0100
Message-ID: <CAJrtwV6TZEsDNUZE-=WC9utq43GoRL5G0td59+6ZX0D8UHNtRA@mail.gmail.com>
To: Heiko Paulheim <paulheim@ke.tu-darmstadt.de>
Cc: public-lod@w3.org, semantic-web@w3.org
On Wed, Jul 4, 2012 at 7:45 AM, Heiko Paulheim
<paulheim@ke.tu-darmstadt.de> wrote:
> Hi all,
>
> I am wondering whether there is a way of finding a SPARQL endpoint for an
> LOD URI, i.e., a function f that behaves like
> f(<http://dbpedia.org/resource/Darmstadt>) = <http://dbpedia.org/sparql>
>
> TimBL's design issues document [1] says:
> "To make the data be effectively linked, someone who only has the URI of
> something must be able to find their way the SPARQL endpoint.  [...]
> Vocabularies for doing this have not yet been standardized."
>
> Is that still the state of affairs? Are there any practical workarounds?
>

Hi,

http://www.w3.org/TR/void/#discovery describes methods for publishers
to let their dataset descriptions be discovered  via a Linked Data
URI.

The publisher can provide a 'back link' in the RDF they return from
the RDF document, to the dataset URI (which then provides a link to
the SPARQL endpoint)
eg:

<thing> foaf:isPrimaryTopicOf <document> .
<document> void:inDataset <dataset> .

Or the publisher can make their dataset description available at
{their domain}/.well-known/void

Sadly I am not sure how wide-spread either of those are amongst
dataset publishers.


As a consumer, you could try going to:

http://dsi.lod-cloud.net/sparql
 and querying for

PREFIX void: <http://rdfs.org/ns/void#>
select distinct ?dataset ?sparql where {
 ?dataset void:uriSpace ?urispace ; void:sparqlEndpoint ?sparql .
 filter(regex('{your URI}', ?urispace))
}


HTH

Keith

> Best,
> Heiko
>
> [1] http://www.w3.org/DesignIssues/LinkedData.html
>
> --
> Dr. Heiko Paulheim
> Knowledge Engineering Group
> Technische Universitšt Darmstadt
> Phone: +49 6151 16 6634
> Fax:   +49 6151 16 5482
> http://www.ke.tu-darmstadt.de/staff/heiko-paulheim
>
>
Received on Wednesday, 4 July 2012 07:14:11 UTC

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