On 06/06/14 16:40, Miguel Bento Alves wrote:
A doubt about processing of jena rules:new triples generated by rules are saved in the model? or processed in runtime, when the rule is invoked? for instance, I have the following triples: eg:A eg:p eg:B . eg:B eg:p eg:C . eg:C eg:p eg:D . and the rule: [rule1: (?a <eg:p> ?b) (?b <eg:p> ?c) -> (?a <eg:p> ?c)] The following triples are saved in the model or are generated every time the rule is invoked?
For the forward engine (which that rule will use unless you override it) then the triples are generated in the separate deductionsModel and not regenerated at each query. In addition the partial matches for each pattern will be stored in the RETE network.
For the backward engine then it depends on tabling. With the backward engine you can set predicates to be tabled (essentially any goal with that predicate in will be cached). So if <eg:p> is tabled then results aren't added to the model but repeats of the same or related queries will reuse information from the tables. If it is not tabled then the information is recreated each time.
Dave
