Apache Jena contains the TDB2 engine which functions as a local datastore for RDF triples.
Here we document how it can be used to create a local triple store of IPTC Sport Schema data which can then be queried to test our sample queries.
tdb2.tdbloader --loc sportdb samples/ttl/*.ttl
(note: should we use –graph to load data into a named graph??)
Once the data is loaded into the TDB2 file, it can be queried using the
tdb2.tdbquery --loc sportdb --query queries/season-team-players.rq
If you install Apache Jena’s Fuseki package (a separate download from the Jena downloads page, then it’s easy to turn the TDB2 file into the data store for a SPARQL server:
fuseki-server --tdb2 --loc sportdb /sport
Fuseki has a Web UI, go to
http://localhost:3030/ to explore it.
Through the Web UI, you can enter SPARQL queries and load more data into the system.
IPTC are hosting a test instance of Fuseki at http://query.sportschema.org/. This contains the ontology files, our test data, and some “canned queries” illustrating how to test the endpoint with SPARQL queries relating to our use cases.
When fuseki is running, you can also query the SPARQL endpoint via HTTP requests
curl http://localhost:3030/sport/query -X POST --data 'query=%0A%0ASELECT+%3Fsubject+%3Fpredicate+%3Fobject%0AWHERE+%7B%0A++%3Fsubject+%3Fpredicate+%3Fobject%0A%7D%0ALIMIT+25' -H 'Accept: application/sparql-results+json,*/*;q=0.9'
Still to come.