[DL] Ontop 1.13: New Release
mrezk at inf.unibz.it
Thu Sep 25 16:31:49 CEST 2014
We are happy to announce the availability of
a Java framework to query ontologies with mappings to databases.
If you are interested in virtual RDF graphs, R2RML mappings and/or
RDFS/OWL2QL reasoning, then -ontop- is for you. The system implements
the cutting edge SPARQL-to-SQL and query optimisation techniques that
allow it to answer SPARQL queries using SQL databases while obtaining
With -ontop-, you don't need to move your data from your already
efficient database in order to enjoy the benefits of the RDF data
model, the SPARQL query language or RDF/OWL2QL inference.
And there is no need for expensive ETL or forward/backward chaining either.
You can use -ontop- as an API, a SPARQL end-point, or as a Protege plugin.
The highlights of this new release include:
-New mechanism to specify DB implicit constraints (such as implicit keys) that are not specified in the DB (this is used for optimisation).
-Command line feature to generate pretty R2RML.
-Stream output in the Protege Plugin.
-Support for Regex operators in the mapping language.
-Proper handling of datatypes in ontology and mappings, including type promotion and type checking.
-Support for HSQL database.
-Improved support for datatypes xsd:date, xsd:time and xsd:gYear
** Issue with nested equivalences in the unfolder.
** Problem with multiple join conditions in R2RML.
** Cancelling running queries in Protege.
** Blank lines in generated sql.
The system is available for FREE at
Please, try it out and help us improve it by sending us your feedback.
Tell us how YOU are using -ontop-!
To start using -ontop- try our new tutorials!
-Easy Tutorial: Using Ontop from Protege
-Easy Tutorial: Using Ontop API from Eclipse
The -ontop- development team
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