D2R Server provides SPARQL access to relational databases. It combines the D2RQ API and Joseki SPARQL Server to map a database's contents into a virtual RDF graph that can be accessed over the SPARQL protocol. It is bundled with a Jetty webserver and aims at being easy to set up and use.
D2R Server is currently in an alpha state. It works for us, but has a minimal feature set and needs much more testing.
Requirements
You need:
- Java 1.4 or newer on the path (check with java -version if you're not sure),
- a D2RQ mapping file that describes how the tables and columns of your database should be mapped into RDF and how to connect to the database; the D2RQ Manual describes how to create one.
Installing and running D2R Server
Extract the archive into a suitable location. Optionally, add the extracted directory (where the d2r-server and d2r-server.bat files reside) to the path.
Change into the directory and run:
./d2r-server path/to/mappingfile.ttl (for Unix)
d2r-server c:\path\to\mappingfile.ttl (for Windows)(mappingfile.ttl is a D2RQ mapping file that describes how your database tables and columns are mapped to RDF and how to connect to the database – the D2RQ Manual describes how to create one)
Open http://localhost:2020/ in a web browser. The SPARQL endpoint is at http://localhost:2020/sparql.
Source code and development
The latest source code is available from the project's CVS repository and can be browsed online.
(Note: SourceForge's CVS service is currently unreliable.)
Support and feedback
You can contact us on the D2RQ mailing list at d2rq-map-devel@lists.sourceforge.net.