Ontop: Answering SPARQL Queries over Relational Databases

Semantic Web J.. 8(3):471--487 2017. Semantic Web Journal outstanding paper award for 2016.

We present Ontop, an open-source Ontology-Based Data Access (OBDA) system that allows for querying relational data sources through a conceptual representation of the domain of interest, provided in terms of an ontology, to which the data sources are mapped. Key features of Ontop are its solid theoretical foundations, a virtual approach to OBDA, which avoids materializing triples and is implemented through the query rewriting technique, extensive optimizations exploiting all elements of the OBDA architecture, its compliance to all relevant W3C recommendations (including SPARQL queries, R2RML mappings, and OWL 2 QL and RDFS ontologies), and its support for all major relational databases.

@article{SWJ-2017,
   title = "Ontop:  Answering SPARQL Queries over Relational Databases",
   year = "2017",
   author = "Diego Calvanese and Benjamin Cogrel and Sarah Komla-Ebri and
Roman Kontchakov and Davide Lanti and Martin Rezk and Mariano
Rodriguez-Muro and Guohui Xiao",
   journal = "Semantic Web J.",
   pages = "471--487",
   number = "3",
   volume = "8",
   doi = "10.3233/SW-160217",
   note = "Semantic  Web  Journal  outstanding paper award for 2016",
}