OWLQ: A language and ontology for stating
conjunctive queries against OWL data
OWLQ provides an ontology of queries.
A query consists of class definitions (in OWL), definition of variables ranging
over these, definition of variables depending on them, and constraints between
these variables. Individual classes and predicates can optionally be considered under
closed-world-semantics. Thus, an OWL query is a graph that describes a conjunctive
OWLQ queries can be evaluated -obviously-, but also analyzed based on the
above notions for satisfiability and containment. The prototype implementation
consists of a Jena-based core with a plugged-in DL Reasoner (Pellet).
OWLQ is used for Queries, tests, and event matching in MARS:
(click on "Register XML Rule" and have a look)
An online interface to the prototype can be found at
Note that it may sometimes be down.
The work is described in the MSc Thesis by Jochen Kemnade:
- An OWL-based Query Language for OWL Data.