ktk

SPARQL CONSTRUCT comparison

I had some days left on a physical machine we used for an EU FP7 research project so I took the chance to compare 3 triplestores (update: added some more based on comments here) I or my colleagues worked with in the past months. I do not want to imply anything with this test, it's just me playing around and having fun with RDF. If you have any comments, add it here.

Hardware

The test platform comprises a dedicated server, not a virtual machine, with the following specification:

• 2 x Intel Xeon E5 2620V2, 2 x (6 x 2.10 GHz) (appears as 24 cores in htop)
• 128 GB buffered ECC RAM

ColinMaudry

SPARQL Queries (with cURL command) on Wikidata

This gist resulted to be just the spark for a proper article, and won't be maintained here anymore.

The SPARQL endpoint is http://wdqs-beta.wmflabs.org/bigdata/namespace/wdq/sparql and it has a Web form to fire queries. However http://www.wikidata.org/prop/direct/P31 ("instance of") tells you what the entity is.

The repository doesn't have named graphs, or at least the SPARQL endpoint rejects graph queries. The classes of entities (rdf:type) are not described in the repository.

To find the HTML page of an entity (such as https://www.wikidata.org/entity/Q866405), simply replace /entity/ with /wiki/.