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Property path query performance problems: help desperately needed.

07291868-dafd-4ac1-a608-b4a39a6efb1fFeb 11 2016 — edited Feb 15 2016

I am new to OracleRDF but not new to triple stores or SPARQL

I have some existing queries that run on various other triple stores (Virtuoso, Allegrograph, Sesame, Jena memory model etc). The graph I am testing against only contains 1600 triples (yes sixteen hundred)

However even simplified queries with property paths either never return or throw a java heap problem (I have 4Gbyte allocated to the Tomcat that is running Joseki)

PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>

PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>

PREFIX owl: <http://www.w3.org/2002/07/owl#>

PREFIX xsd: <http://www.w3.org/2001/XMLSchema#>

SELECT  distinct *

               WHERE {

                {

                                ?property rdfs:subPropertyOf* ?sproperty .

                               ?sproperty rdfs:domain ?sdomain .

                                ?sproperty rdf:type ?propertyType .

                                ?property rdfs:range ?r .

               }

}

i have tried every combination of hints to get this query to work. For example:


PREFIX ORACLE_SEM_FS_NS: <http://oracle.com/semtech#TIMEOUT=100,ASSERTED_ONLY,JENA_EXECUTOR>


The problem is this is not even close to the complexity of the queries i really need to run (and already run on 4 different triple stores without any issue).


I have looked at all of the hints available and tried most permutations.


What do I do other than switch to a different triple store?


Help!!!

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Added on Feb 11 2016
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