graffiti

https://github.com/angdraug/graffiti

Graffiti is an RDF store based on dynamic translation of RDF queries into SQL. Graffiti allows one to map any relational database schema into RDF semantics and vice versa, to store any RDF data in a relational database. Graffiti uses Sequel to connect to database backend and provides a DBI-like interface to run RDF queries in Squish query language from Ruby applications.