Sebastian, you can use Neo4j with RDF, we are running the Tinkerpop RDF components. I am working on a RDF plugin, see https://github.com/peterneubauer/sparql-plugin that runs inside the Neo4j Server and talks REST.
Java wise you can do like https://github.com/peterneubauer/sparql-plugin/blob/master/src/main/java/org/neo4j/server/plugin/sparql/SPARQLPlugin.java#L62 and then execute queries like the Berlin dataset with something like https://github.com/peterneubauer/sparql-plugin/blob/master/src/test/java/org/neo4j/server/plugin/sparql/BerlinDatasetTest.java Does that help? Cheers, /peter neubauer GTalk: neubauer.peter Skype peter.neubauer Phone +46 704 106975 LinkedIn http://www.linkedin.com/in/neubauer Twitter http://twitter.com/peterneubauer http://www.neo4j.org - NOSQL for the Enterprise. http://startupbootcamp.org/ - Öresund - Innovation happens HERE. 2011/11/13 Sébastien HARISPE <harispe.sebast...@gmail.com>: > Hi all, > > First of all, Thx a lot for your amazing work, simply astonishing... > Below three questions related to my interest in using Neo4J as a Graph DB > on top of which I want to test algorithms dedicated to large semantic > graphs (OWL/RDF based). > It would be nice if you could help me answer them. > > > A -Using Neo4J with semantic web technologies like RDF/OWL/SPARQL: > > How does Neo4J interact with these technologies? > > I found/read: > > - an old post explaining how to load OWL into Neo4J using Jena API > [1]<http://sujitpal.blogspot.com/2009/05/using-neo4j-to-load-and-query-owl.html> > . > - interesting classes in the org.neo4j.meta.model package > [2<http://components.neo4j.org/neo4j-meta-model/snapshot/> > > ,3<http://components.neo4j.org/neo4j-meta-model-import/snapshot/apidocs/org/neo4j/meta/input/owl/Owl2GraphDb.html>] > but I can't locate the package in the 1.5 apidocs > [4]<http://components.neo4j.org/neo4j/1.5/apidocs/> > . > - that the org.neo4j.rdf and org.neo4j.meta do not follow the core > components release, are they currently supported? > - a ticket related to the addition of SPARQL plugin to the Neo4J server, > which means that semantic processes are part of your preoccupations ;). > > Can you detail the position of Neo4J considering OWL/RDF/SPARQL > technologies? > I can't easily find documentation about Neo4J and OWL > [5<http://wiki.neo4j.org/content/OWL,_SPARQL,_SAIL,_and_RDF>], > the use of RDF and SPARQL is well detailed however > [6]<http://wiki.neo4j.org/content/RDF_/_SPARQL_Quickstart_Guide> > . > I also read about Sail on top of Neo4j > [7]<https://github.com/datablend/neo4j-sail-test>, > and to be honest, I'm quite lost... > > Do you think Neo4J is an interesting solution to interact with these > technologies, that is to say, loading OWL specification as graph > (simplification of the spec e.g classes, instances relationships between > them), adding RDF triplet and using SPARQL? > > > > B - Algorithm implementations: > > As you know many graph algorithms need to store temporary results e.g. > Dijkstra stores shortest path cost for all nodes during execution. > Due to the size of the graphs, storing this information in memory is not > possible most of the time, so how do you manage this information? Temporary > node properties? Is there guidance to implement algorithms using Neo4J? > > > > C - In-memory usage of Neo4J: > > In-memory graphs are very pleasant in order to perform certain CPU > consuming algorithmic treatments on a reduced part of the graph. > Considering an old post > [8]<http://lists.neo4j.org/pipermail/user/2010-February/002719.html>, > a proposed alternative was to rollback the transaction after the treatment, > i.e load the graph without flushing it. This make sense if you want to load > a new graph but is it possible to load a specific part of an existing graph > database in memory? Moreover, in the previously cited post you said that > you planned to add an in-memory implementation but I can't find more > information in the 1.5 doc, did I missed something? > > Thx, > > SH > > [1] > http://sujitpal.blogspot.com/2009/05/using-neo4j-to-load-and-query-owl.html > [2] http://components.neo4j.org/neo4j-meta-model/snapshot/ > [3] > http://components.neo4j.org/neo4j-meta-model-import/snapshot/apidocs/org/neo4j/meta/input/owl/Owl2GraphDb.html > [4] http://components.neo4j.org/neo4j/1.5/apidocs/ > [5] http://wiki.neo4j.org/content/OWL,_SPARQL,_SAIL,_and_RDF > [6] http://wiki.neo4j.org/content/RDF_/_SPARQL_Quickstart_Guide > [7] https://github.com/datablend/neo4j-sail-test > [8] http://lists.neo4j.org/pipermail/user/2010-February/002719.html > _______________________________________________ > Neo4j mailing list > User@lists.neo4j.org > https://lists.neo4j.org/mailman/listinfo/user > _______________________________________________ Neo4j mailing list User@lists.neo4j.org https://lists.neo4j.org/mailman/listinfo/user