2011/3/17 Enrico Daga <[email protected]>: >> >> It seems to me by reading the source code of >> TcManager#executeSparqlQuery and JenaSparqlEngine#execute and >> TcDataset#getNamedGraph that the clerezza sparql execution should be >> able to perform queries accross several graphs. The second argument of >> TcManager#executeSparqlQuery is just the default named graph used when >> the sparql query does not have FROM clause. >> >> Please try to build a SPARQL query with an explicit FROM clause >> pointing to a graph id used by kres to check this assertion. If it >> works, try another query that mixes triples from both graphs >> (reengineer and enhancer) using the GRAPH keyword in the body of the >> SPARQL query as in >> http://www.w3.org/TR/rdf-sparql-query/#restrictByLabel for instance. >> >> If it does not work, i think we should ask the question on the >> clerezza mailing list directly instead. > Thank you Olivier. Yes, it looks like it should support this. > So I can assume that the answer to my question is YES, Stanbol has a > Sparql endpoint which should cover all graphs in the store. So we > don't need additional components for that, just use the /sparql path > and maybe improve it, if needed. > I'll do more test about it.
If your tests don't work as expected, or the performance is too poor, this might be the consequence of some design limitations of the current TdbTcProvider / JenaSparqlEngine implementation that is overly generic. I have discussed this issue with the clerezza developers on the best way to improve upon this and the results is available in these two issues: https://issues.apache.org/jira/browse/CLEREZZA-466 https://issues.apache.org/jira/browse/CLEREZZA-467 I am sure they would appreciate to review patches should you want to implement those improvements. -- Olivier http://twitter.com/ogrisel - http://github.com/ogrisel
