Hi Emillio, Two small follow-up questions:
1) Having two different APIs for query and update SPARQL means that in a SPARQL endpoint we should first try the query and if it throws exception then we try update API? Or there is something else to deal with the separation between the two APIs in processing a general SPARQL request? 2) Speaking about synchronization, does it mean that query model is thread safe and we do not have to concern concurrent query requests? We only need to do that for update? Thanks, Milorad >________________________________ > From: Emilio Migueláñez Martín <[email protected]> >To: [email protected]; Milorad Tosic <[email protected]> >Sent: Tuesday, February 7, 2012 12:08 PM >Subject: Re: is SPARQL UPDATE supported in TDB > >Hi Milorad, > >The SPARQL UPDATE doesn't use the same API calls as other SPARQL queries. > >Try the following > >model.enterCriticalSection(Lock.WRITE); > > ry { > UpdateRequest updateRequest = UpdateFactory.create(querystr); > UpdateAction.execute(updateRequest, m_triplestore); > > } finally { > m_triplestore.commit(); > TDB.sync(m_triplestore); > model.leaveCriticalSection(); > } > >Some examples of ARQ's SPARQL Update support are to be found in the download >in src-examples/arq/examples/update. > >Regards, >Emilio > >On 7 Feb 2012, at 10:58, Milorad Tosic wrote: > >> Hi, >> >> Does TDB support SPARQL UPDATE? >> >> >> I have a simple Java code that instantiates TDB like: >> ... >> Query query = QueryFactory.create(querystr); >> QueryExecution qe = QueryExecutionFactory.create(query, >>m_triplestore); >> >> ResultSet results = qe.execSelect(); >> ResultSetFormatter.out(out, results, query); >> >> ... >> >> Initially, TDB is empty. >> >> >> For querystr = >> >> SELECT * WHERE { ?x ?p ?o }, >> >> I got expected result i.e. an empty set of triplets. >> >> However, for querystr = >> PREFIX eg: <http://example.org/ontology#> >> INSERT DATA >> { >> eg:dummySubject1 eg:dummyPredicate2 eg:dummyObject2. >> } >> TDB didn't recognize the "INSERT DATA" keyword, and reported: >> com.hp.hpl.jena.query.QueryParseException: Encountered " <INSERT_DATA> >> "INSERT DATA "" at line 2, column 1. >> Was expecting one of: >> "prefix" ... >> "select" ... >> "describe" ... >> "construct" ... >> "ask" ... >> >> >> My configuration is like follows: >> >> arq-2.8.7.jar >> jena-2.6.4.jar >> tdb.0.8.10.jar >> >> Thanks, >> Milorad > >--- >Emilio Migueláñez Martín >[email protected] > > > > >
