Inferencing with OWL rulebase

Question

Hi
I'm using a 11gR2 DB and I would like to remove uncertainties about the version of OWL that is supported.
I use Protégé version 4.0.1 and 3.4.3; I would prefer to use 4.0.1 because it supports OWL2. In both cases, I can load the ontologies without problems. I have the feeling (yet to be demonstrated) that triples created with references to OWL are stored but not processed.
The Oracle doc says that the OWLPrime RB is empty (note 1); does it mean that any owl predicated will not be inferred?
Should I stick with pure rdf ontologies (SEM_RULEBASES('RDFS','pizza_rb'),?
Will OWLPrime be available anytime soon?
Best regards
note 1: Oracle Spatial Resouce Description Framework, page 1-10.

Answer 1

Hi,
OWLPrime is a system defined rulebase. Meaning that its inference logic (many owl related rules that Oracle uses) is implemented in the code. It is "empty" because we do not expose those rules explicitly. So you don't see them. However, the OWL semantics are certainly recognized.
A few examples of using OWLPrime rulebase is as follows.
-- This one performs inference on lubm benchmark and university ontology.
exec sem_apis.create_entailment('lubm50_idx',sem_models('lubm50','univ'),sem_rulebases('owlprime'));
-- This one performs inference on lubm benchmark and university ontology. In addition, some of the new inference
-- components (introduced in 11.2) are added.
exec sem_apis.create_entailment('lubm50_idx',sem_models('lubm50','univ'),sem_rulebases('owlprime'),SEM_APIS.REACH_CLOSURE, 'INTERSECT,SVFH, INTERSECTSCOH, THINGH, THINGSAM');
We have similar APIs on Java side (provided by Jena Adaptor) too.
Cheers,
Zhe Wu