5. The method set forth in claim 1 wherein: in the step of obtaining results, the RDF triples belonging to the set are represented by an RDF triples table in the relational database management system.
6. The method set forth in claim 5 wherein: the relational database system includes one or more optimization objects for optimizing queries on the RDF triples table; and in the step of obtaining results, the relational database management system uses the optimization objects to optimize the query on the RDF triples table.