OBDA with the Ontop Framework

Diego Calvanese, Benjamin Cogrel, Elem Güzel Kalayci, Sarah Komla Ebri, Roman Kontchakov, Davide Lanti, Martin Rezk, Mariano Rodriguez-Muro, and Guohui Xiao

Proc. of the 23rd Italian Symp. on Advanced Database Systems (SEBD 2015). 2015.

Ontology-based data access (OBDA) has become a popular paradigm for accessing data stored in legacy sources using Semantic Web technologies. In the OBDA setting, users access the data through a conceptual layer, which provides a convenient query vocabulary abstracting from specific aspects related to the data sources. This conceptual layer is typically expressed as an RDF(S) or OWL ontology, and it is connected to the underlying relational databases using R2RML mappings. When the ontology is queried in SPARQL, the OBDA system exploits the mappings to retrieve elements from the data sources and construct the answers expected by the user. Different approaches for query processing in OBDA have been proposed. We focus here on the virtual approach, which avoids materializing triples retrieved through mappings and answers the SPARQL queries by translating them into SQL queries over the data sources. In this paper we present our mature open-source OBDA framework Ontop, which supports all W3C standards related to OBDA, and which produces efficiently executable SQL queries.

   title = "OBDA with the Ontop Framework",
   year = "2015",
   author = "Diego Calvanese and Benjamin Cogrel and Güzel Kalayci,
Elem and Komla Ebri, Sarah and Roman Kontchakov and Davide Lanti and
Martin Rezk and Mariano Rodriguez-Muro and Guohui Xiao",
   booktitle = "Proc. of the 23rd Italian Symp. on Advanced Database Systems
(SEBD 2015)",
   pages = "296--303",