Thanks for the reply Chris. Can somebody please describe what is the expected behaviour of listInstances as explained in my previous email?
Thank you. Regards Panagiotis On Thu, Jan 24, 2013 at 3:46 PM, Chris Dollin <chris.dol...@epimorphics.com>wrote: > On Thursday, January 24, 2013 03:08:35 PM Panagiotis Papadakos wrote: > > > Finally, regarding performance,I would like to know if jena internally > > uses indices that can provide me fast access from classes to instances > and > > from instances to classes. Else I probably will have to implement them. > > (a) Don't assume in advance that there will be a performance problem > that's the one you expect. > > (b) listStatements(null, RDF.type, MyClass) will deliver you an iterator > over all the statements which say that the subject is an instance > of MyClass. > > Implementations of Model, or rather, the underlying Graph, will > (typically) have indexes that make this reasonably fast. The built-in > memory graph has S, P, and O indexes; TDB has SP, PO and SO > (I think) indexes as well. > > And you can run listStatements the other way to find classes > given their instances. > > Chris > > -- > "I know it was late, but Mountjoy never bothers, /Archer's > Goon/ > so long as it's the full two thousand words." > > Epimorphics Ltd, http://www.epimorphics.com > Registered address: Court Lodge, 105 High Street, Portishead, Bristol BS20 > 6PT > Epimorphics Ltd. is a limited company registered in England (number > 7016688) > > -- http://www.flickr.com/photos/papadako
