From Semantic Web Standards


Name of the tool: Ontop
Home page: Ontop VKG
Date of latest release:
Programming language(s) that can be used with the tool: Java
Relevant semantic web technologies: RDF, RDFS, OWL, SPARQL, R2RML
Categories: SPARQL Endpoint, Converter, OWL Reasoner, RDB2RDF, RDF Generator, RDFS Reasoner, Reasoner
See also:
Public mailing list: http://groups.google.com/d/forum/ontop4obda
Preferred project URI: http://ontop-vkg.org
DOAP reference:
Company or institution:

(Tool description last modified on 2022-06-23.)


-ontop- is a platform to query databases as Virtual RDF Graphs using SPARQL. It's extremely fast and is packed with features.

Packed with useful features and components that will help you deploy it in almost any use case. Highlights include:

  • SPARQL 1.1 Support
  • Intuitive/powerful mapping language
  • Support for free and commercial DBMS
  • Compatible with DBMS federation tools
  • Providers for Sesame and OWLAPI
  • Integrated with Protege 5.x
  • SPARQL end-point

The SPARQL engine supports the following entailment regimes out of the box: OWL 2 QL, RDFS, and experimentally SWRL. With inference you will be able to apply virtual RDF and RDB2RDF /OBDA technology in use cases reserved for traditional OWL reasoners (slow with lots of data) or RDF triples stores based on forward or backward chaining (inefficient reasoning). Interesting use cases for inference in RDB2RDF/OBDA include:

  • On-the-fly Ontology-based Data Access
  • SPARQL over RDFS/OWL mappings
  • Data Integration with DB federation

Extremely high performance, even in the presence of very large data sets, complex queries and large ontologies. ontop implements the latest generation query rewriting techniques that translate your SPARQL into SQL in the best possible way. The SQL queries are so efficient that they often allow provide 10x times better performance than other SPARQL engines (open source or even commercial), and in complicated queries/data sets, up to 500x times.

Visit our website: https://ontop-vkg.org/

Clone ontop from github https://github.com/ontop/ontop

Check the documentation, tutorials, and examples: https://github.com/ontop/ontop/wiki

Or send us an email to our mailing list: ontop4obda (((AT))) googlegroups.com