- From: Manuel Salvadores <ms8@ecs.soton.ac.uk>
- Date: Tue, 28 Sep 2010 09:32:33 +0100
- To: Riccardo Tasso <tasso@elet.polimi.it>
- Cc: semantic-web@w3.org
- Message-ID: <EMEW3|9def808085b355876b479fe555f61d3dm8R9Xw03ms8|ecs.soton.ac.uk|3331FBC4-5A85>
Riccardo, 4sr [1] is an extension of 4store [2] that allows you to SPARQL with RDFS entailments. 4sr has a parameter to disable the RDFS reasoning. When running 4s-query by adding "-n" option. When running the SPARQL endpoint by adding "no-reasoner=true" in the HTTP request. There is a short demo at [3]. If your reasoning is at the RDFS level then 4sr might be a good option for you. Best, Manuel [1] http://4sreasoner.ecs.soton.ac.uk/ [2] http://4store.org/ [3] http://4sreasoner.ecs.soton.ac.uk/demo.html On Sep 27, 2010, at 3:19 PM, Andrea Splendiani wrote: > Yes, you can do that. > For updates, it may be more tricky. > > In brief: > > In Jena/Joseki you build up a model via a spec file. > > Imagine your data files (the triplestore, not the rdf) are at > /exampled/dir/data, > > you can build both a plain model which holds /example/dir/data or an an > infmodel, which has the same data and your choice of reasoners. > > You can plug any of the two into Joseki (mutiple instances on different > ports) > > Now: > > if you use TDB as a Jena backend, I'm not sure it is safe versus concurrent > accesses (the two joseki accessing the same files). Not for sure in writing, > perhaps ok in reading. > > You can use SDB (which is a relational backed triplestore): less performant, > but should support concurrent R/W access. > > You can find more info on the Jena mailing list. If you check the archieves, > I recall some message about TDB/SDB and concurrency. > > How big is your data ? > > SDB il less performant than TDB, for big data (well... relatively) this can > make a difference. > > ciao, > Andrea > > Il giorno 27/set/2010, alle ore 16.09, Riccardo Tasso ha scritto: > >> Grazie Andrea, >> but what if I need to access data from a SPARQL endpoint? Could I >> use Joseki to query two different models (one inferred, and one >> "simple") such that they are based on the same data? Please note that >> I'd like to have the possibility to execute updates too. >> >> Cheers, >> Riccardo >> >> On 27/09/2010 15:19, Andrea Splendiani wrote: >>> Hi, >>> >>> you can also use Jena for this. >>> You have a choice of reasoners which you can attach to the RDF model, in >>> your case you can use either a minimal "transitive reasoner" and (bits > of) a >>> rule based reasoner. You can select which rules you want to apply, or > choose >>> among default configurations. >>> If you define your own rules, use backward rules. >>> >>> at the SPARQL level, this is completely transparent. But you can change >>> reasoners dynamically programmatically if you need. >>> >>> ciao, >>> Andrea >>> >>> Il giorno 22/set/2010, alle ore 12.06, Riccardo Tasso ha scritto: >>> >>> >>>> I'm interested in executing SPARQL queries over an endpoint, sometimes >>>> with reasoning, sometimes without (dynamically). The reasoning task I >>>> need are RDFS plus owl:sameAs. It is also an interesting question to me, >>>> wheter a SPARQL query could specify if the results should contain >>>> inferred triples or not. >>>> >>>> Do you know a triple store, possibly supporting named graphs, suitable >>>> to my needs? >>>> >>>> Thanks, >>>> Riccardo >>>> >>>> >>>> >>> Andrea Splendiani >>> Senior Bioinformatics Scientist >>> Centre for Mathematical and Computational Biology >>> +44(0)1582 763133 ext 2004 >>> andrea.splendiani@bbsrc.ac.uk >>> >>> >>> >>> >> > > Andrea Splendiani > Senior Bioinformatics Scientist > Centre for Mathematical and Computational Biology > +44(0)1582 763133 ext 2004 > andrea.splendiani@bbsrc.ac.uk > > > >
Received on Tuesday, 28 September 2010 08:35:01 UTC