Re: Announcing the release of the Wikidata Query Service

On 08.09.2015 17:52, Miguel wrote:
> Great news!
>
> I see that the UI uses a public (and CORS-enabled)SPARQL endpoint
> available at
> https://query.wikidata.org/bigdata/namespace/wdq/sparql
>
> I don't see this SPARQL endpoint documented as such, but I hope it will
> be kept publicly available.

Indeed, I should have given some more documentation -- details in this 
email. The endpoint you found is documented here:

https://www.mediawiki.org/wiki/Wikidata_query_service/User_Manual

If it should ever change, I am sure WMF can set up a redirect to keep 
links working.

I also should have pointed explicitly to the list of current example 
queries. You can do some very interesting things with this data (and 
with SPARQL, of course ;-), but some may not be obvious if you are not 
familiar with our data:

https://www.mediawiki.org/wiki/Wikibase/Indexing/SPARQL_Query_Examples

Short guideline for getting started with simple queries:

* Use wd:Q1234 (<http://www.wikidata.org/entity/Q1234>) to refer to an 
item ("data page") on Wikidata. You can find an item id, e.g., by 
browsing Wikipedia and clicking the link "Wikidata item" on the left.

* Use wdt:P1234 (<http://www.wikidata.org/prop/direct/P1234>) to refer 
to *simplified* direct versions of Wikidata properties. Property ids can 
be searched for on Wikidata, or browsed for by clicking property names 
on any item page.

"Simplified" means that there is a direct connection from subject to 
property value -- no references (provenance), no qualifiers (statement 
annotations); that the value is simplified (e.g. no precision 
information for numbers); and that only data for the statements of the 
highest rank will be included (e.g., only current population numbers, no 
historic ones).

* For how to access the full data with all details, see the example 
query for "largest cities with a female mayor" and read the documentation:

https://www.mediawiki.org/wiki/Wikibase/Indexing/RDF_Dump_Format

It also helps to look at some Wikidata pages to get an idea of what is 
there. The showcase items give a good overview:

https://www.wikidata.org/wiki/Wikidata:Showcase_items

Cheers,

Markus


>
>
> Il giorno mar 8 set 2015 alle ore 05:28 Olivier Rossel
> <olivier.rossel@gmail.com <mailto:olivier.rossel@gmail.com>> ha scritto:
>
>     Brillant!!!
>
>     Envoyé de mon iPhone
>
>     Le 8 sept. 2015 à 10:03, Markus Kroetzsch
>     <markus.kroetzsch@tu-dresden.de
>     <mailto:markus.kroetzsch@tu-dresden.de>> a écrit :
>
>      > Dear SPARQLers,
>      >
>      > The Wikimedia Foundation has just announced its first official
>     live query service for Wikidata, based on SPARQL.
>      >
>      > Cheers,
>      >
>      > Markus
>      >
>      >
>      > -------- Forwarded Message --------
>      > Subject:    [Wikidata] Announcing the release of the Wikidata
>     Query Service
>      > Date:    Mon, 7 Sep 2015 15:29:02 -0700
>      > From:    Dan Garry <dgarry@wikimedia.org
>     <mailto:dgarry@wikimedia.org>>
>      > Reply-To:    Discussion list for the Wikidata project.
>      > <wikidata@lists.wikimedia.org <mailto:wikidata@lists.wikimedia.org>>
>      > To: wikidata-l@lists.wikimedia.org
>     <mailto:wikidata-l@lists.wikimedia.org>
>      >
>      >
>      >
>      > The Discovery Department at the Wikimedia Foundation is pleased to
>      > announce the release of the Wikidata Query Service
>      > <https://www.mediawiki.org/wiki/Wikidata_query_service>! You can find
>      > the interface for the service at https://query.wikidata.org.
>      >
>      > The Wikidata Query Service is designed to let users run queries
>     on the
>      > data contained in Wikidata. The service uses SPARQL
>      > <https://en.wikipedia.org/wiki/SPARQL> as the query language. You can
>      > see some example queries in the user manual
>      > <https://www.mediawiki.org/wiki/Wikidata_query_service/User_Manual>.
>      >
>      > Right now, the service is still in beta. This means that our goal
>      >
>     <https://www.mediawiki.org/wiki/Wikimedia_Engineering/2015-16_Q2_Goals#Wikidata_Query_Service>
>     is
>      > to monitor of the service usage and collect feedback about what
>     people
>      > think should be next. To do that, we've created the Wikidata Query
>      > Service dashboard <https://searchdata.wmflabs.org/wdqs/> to track
>     usage
>      > of the service, and we're in the process
>      > <https://phabricator.wikimedia.org/T111403> of setting up a feedback
>      > mechanism for users of the service. Once we've got monitored the
>     usage
>      > of the service for a while and got user feedback, we'll decide on
>     what's
>      > next for development of the service.
>      >
>      > If you have any feedback, suggestions, or comments, please do send an
>      > email to the Discovery Department's public mailing list,
>      > wikimedia-search@lists.wikimedia.org
>     <mailto:wikimedia-search@lists.wikimedia.org>
>      > <mailto:wikimedia-search@lists.wikimedia.org
>     <mailto:wikimedia-search@lists.wikimedia.org>>.
>      >
>      > Thanks,
>      > Dan
>      >
>      > --
>      > Dan Garry
>      > Lead Product Manager, Discovery
>      > Wikimedia Foundation
>      >
>      >
>      > <Attached Message Part>
>

-- 
Markus Kroetzsch
Faculty of Computer Science
Technische Universität Dresden
+49 351 463 38486
http://korrekt.org/

Received on Tuesday, 8 September 2015 16:10:23 UTC