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  1. Blazegraph (by SYSTAP)
  2. BLZG-2079

Wrong results for fully constrained "+" property path

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      Description

      Consider data

      <http://C1> rdfs:subClassOf <http://C2> .
      

      and query

      SELECT * WHERE {
        <http://C1> rdfs:subClassOf+  <http://C3> . 
        BIND(5 AS ?y)
      } 
      

      The query returns a result (i.e., ?y -> 5), although there's obviously no transitive subClassOf connection between C1 and C3 in the data. Accordingly, an ASK query

      ASK {
        <http://C1> rdfs:subClassOf+  <http://C3> . 
      } 
      

      returns true (instead of the expected result false), the reason being that the property path expression returns a single (empty) result item rather than no result. Note that the equivalent query

      SELECT * WHERE {
       <http://C1> rdfs:subClassOf+  ?x. 
        BIND(5 AS ?y)
       FILTER(?x = <http://C3>).
      } 
      

      gives no result as expected.

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            Assignee:
            michaelschmidt michaelschmidt
            Reporter:
            michaelschmidt michaelschmidt
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              Updated:
              Resolved: