Thanks Andy, Can you point me to the documentation/examples regarding the bulk-loading with RDFS forward-chaining that you advise below. The only relevant doc I could find is: "http://incubator.apache.org/jena/documentation/tdb/commands.html#tdbloader ", which is not very informative.
Regards Taha On 25/02/2012 18:15, "Andy Seaborne" <[email protected]> wrote: >On 25/02/12 14:03, Damian Steer wrote: >> >> On 25 Feb 2012, at 04:11, Osman, Taha wrote: >> >>> Hi, >> >> Hi Taha, >> >> Apologies for the brief reply. >> >>> we were >>> surprised that Jena TDB's (0.8.10) response time was extremely slow in >>> general and did not return any results (Java runs out of heap space) >>>for >>> all the UOBM queries even while using the least expressive RDFS >>>reasoning. >>> Can you shed light on the matter? >> >> >>> and here is how we fire the queries: >>> >>> Model jenaModel = TDBFactory.createModel(rootDirPath + repoName); >>> InfModel jenaInfModel = ModelFactory.createRDFSModel(jenaModel); >> >> Here's the problem. You're not really testing TDB here, but TDB with >>an in-memory reasoner on top. This will also prevent TDB optimising >>queries, and use heap space that TDB wouldn't. >> >> IIRC the TDB loader has an option to perform RDFS reasoning as you >>load. That should work much better. > >The command is riot.infer > >> >> Damian > >and then using the bulkloader is faster that reading in through the API. > > Andy > DISCLAIMER: This email is intended solely for the addressee. It may contain private and confidential information. If you are not the intended addressee, please take no action based on it nor show a copy to anyone. In this case, please reply to this email to highlight the error. Opinions and information in this email that do not relate to the official business of Nottingham Trent University shall be understood as neither given nor endorsed by the University. Nottingham Trent University has taken steps to ensure that this email and any attachments are virus-free, but we do advise that the recipient should check that the email and its attachments are actually virus free. This is in keeping with good computing practice.
