11. The apparatus of claim 10 , further comprising an ontology schema path generation unit which searches for ontology schema paths between classes with respect to all classes stored in the ontology schema database and builds the ontology schema path database.
11. The apparatus of claim 10 , further comprising an ontology schema path generation unit which searches for ontology schema paths between classes with respect to all classes stored in the ontology schema database and builds the ontology schema path database. 12. The apparatus of claim 11 , wherein if an update of the ontology schema database is detected, the ontology schema path generation unit searches for an ontology schema path of the updated class and updates the ontology schema path database.