morph-RDB [1] (formerly called ODEMapster) is an RDB2RDF engine developed by the Ontology Engineering Group, which follows the R2RML specification (http://www.w3.org/TR/r2rml/). morph-RDB supports two operational modes:

• Data upgrade, which consists in generating RDF data from a relational database according to the R2RML mapping descriptions.
• Query translation, which allows evaluating SPARQL queries over a virtual RDF dataset, by rewriting those queries into SQL according to the R2RML mapping descriptions.

morph-RDB outperforms similar state-of-the-art tools (D2R) and query translation algorithms (e.g., the one proposed by Chebotko and colleagues in 2009) by employing various types of optimisations during the query rewriting process, so as to generate more efficient SQL queries. Some of these optimisations are self-join elimination, subquery elimination, and left-outer join elimination. morph-RDB has been tested with the BSBM synthetic benchmark and has been successfully deployed in various Spanish/EU projects (Integrate, Répener, and BizkaiSense) .

At the moment, morph-RDB works with relational database management systems like MySQL, PostgreSQL and MonetDB. In addition, morph-RDB has also been extended to support Google Fusion Tables in a project called morph-GFT [2] [5], and we are currenly integrating it with our Linked Data Platform implementation (LDP) [3] [4].

The morph-RDB project repository can be found at https://github.com/oeg-upm/morph-rdb and the instructions of how to use it can be found at https://github.com/oeg-upm/morph-rdb/wiki.

[1] Freddy Priyatna, Oscar Corcho, Juan Sequeda. Formalisation and Experiences of R2RML-based SPARQL to SQL query translation using Morph. World Wide Web Conference (WWW 2014). (To Appear)
[2] Freddy Priyatna, Carlos Buil Aranda, Oscar Corcho. Applying SPARQL-DQP for Federated SPARQL Querying over Google Fusion Tables. Extended Semantic Web Conference (ESWC 2013) demo track. link
[3] Mihindukulasooriya, N., García-Castro, R., Esteban-Gutiérrez, M.: Linked Data Platform as a novel approach for Enterprise Application Integration. (Oct 2013)
[4] Mihindukulasooriya, N., Priyatna F., Corcho, O., García-Castro, R. and Esteban-Gutiérrez, M. morph-LDP: An R2RML-based Linked Data Platform implementation. The 11th Extended Semantic Web Conference 2014 Demo Session, Crete, Greece.
[5] https://github.com/oeg-upm/morph-gft