ObjectLogic is the primary query language for OntoBroker. It allows all kinds of complex queries. The following query asks for all instances of the concept "Person":

?- ?X:Person.

It is also possible to start more complex queries which contain disjunctions, negations and built-ins:

?- (?X:Person OR ?X:Human) AND NOT ?X[livesIn->Karlsruhe] AND ?X[hasAge->?AGE] AND ?AGE < 40.

For more details on ObjectLogic, please consult the ObjectLogic reference guide in the OntoBroker installation folder.