This paper presents an extension of the ontology-based data access platform
Ontop that supports answering SPARQL queries under the OWL 2 QL direct
semantics entailment regime for data instances stored in relational databases.
On the theoretical side, the authors show how any input SPARQL query, OWL 2 QL ontology and R2RML mappings can be rewritten to an equivalent SQL query
solely over the data. On the practical side, they present initial experimental results demonstrating that by applying the Ontop technologies.
URL: http://www.ghxiao.org/publications/2014-iswc-sparql-ql-full.pdf
Keywords: R2RML, Web Ontology Language (OWL), Entailment regimes, Ontology-Based Data Access (ODBA), Structured Query Language (SQL)
Author: Zakharyaschev, Michael
Language: http://id.loc.gov/vocabulary/iso639-2/eng
Time required: P45M
Educational use: instruction
Educational audience: student
Interactivity type: expositive
- Knows methods such as Direct Mapping of Relational Data to RDF (2012) for transforming data from the relational model (keys, values, rows, columns, tables) into RDF graphs.
- Understands the difference between SQL query language (which operates on database tables) and SPARQL (which operates on RDF graphs).
- Uses common entailment regimes and understands their uses.