Hello,
I am using the following Sparql query against a TDB store:
SELECT *
WHERE {
?pat a nci:Patient .
?pat ec:Has_Id ?patId .
?findingProp rdfs:subPropertyOf ec:Has_Finding .
?pat ?findingProp ?finding .
?finding a ?findingType .
}
When I run this query WITHOUT the last triple (the bolded line), it returns the
correct result within seconds.
But when I run this query WITH the last triple, the query runs a very long
time. I do not know how long b/c I cancelled it after 1 hour.
This difference in behavior seems unexpected to me since I would assume that
the query processor already bound ?finding and getting the rdf:type of an
already known resource should not be a problem.
I assume that the problem actually stems from the 2 triples before, where I
dynamically define the property (?findingProp). I tried the same query with a
single property instead of ?findingProp and the query ran fine.
Is it combination of ?findingProp and the last triple that throws the query
processor of or am I asking for something in the query that I did not intend?
My TDB store contains the NCI thesaurus, my own extensions plus individuals for
my patient data. Everything is in the default graph.
Thanks for any help!
-Wolfgang
