Dear Jena Developers, I am newbie to Jena and SDB. I meet some problems while executing SPARQL queries on the RDF data with the SDB. I use SDB store to store the pure RDF data. It is successful. I check the database and the RDF data is there. When I use the following codes to query the RDF data on the model. It is fine, and I get the correct result. Model data_model = SDBFactory.connectDefaultModel(store); OntModel ontmodel = ModelFactory.createOntologyModel(OntModelSpec.OWL_DL_MEM, null); ontmodel.add(data_model); QueryExecution qe = QueryExecutionFactory.create(query, ontmodel);
However, when I use SDB dataset to query the same SDB store with the same query, I cannot get any result. Actually these codes are exactly the same with the example. Dataset ds = DatasetStore.create(store); QueryExecution qe= QueryExecutionFactory.create(queryString, ds); PS, the following code also cannot work. Model data_model = SDBFactory.connectDefaultModel(store); OntModel ontmodel = ModelFactory.createOntologyModel(OntModelSpec.OWL_DL_MEM, data_model); QueryExecution qe = QueryExecutionFactory.create(query, ontmodel); Could you kindly tell me what is the problem? Thank you very much! Shiyan
