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  1. Blazegraph (by SYSTAP)
  2. BLZG-837

artificial test case fails

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    Details

    • Type: Bug
    • Status: In Progress
    • Resolution: Unresolved
    • Affects Version/s: BIGDATA_RELEASE_1_2_2
    • Fix Version/s: None
    • Component/s: Bigdata SAIL
    • Labels:
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      Description

      This test case does not give the right results, when there is at least one triple

      SELECT * { 
      
         { SELECT ("3" + 4 as ?X ) 
           {}
         }
         FILTER EXISTS { ?X ?Y ?Z }
      }
      

      It returns the empty result set, the correct answer is a single result with X unbound.
      There are comments in StaticAnalysis.java that suggest that it was written with the belief that the error in the projection causes the projection to be empty rather than ?X to be unbound in the projection.

      Chapter and verse concerning this case are:

      http://www.w3.org/TR/2013/REC-sparql11-query-20130321/#sparqlSelectExpressions

       X := Extend(X, var, expr)
      

      and
      http://www.w3.org/TR/2013/REC-sparql11-query-20130321/#defn_extend

      Extend(?, var, expr) = ? if var not in dom(?) and expr(?) is an error
      

      Judging by the comments in the code, this was implemented at a time when it was believed that the error would result in no solutions, rather than an unbound var.

      I raise this case since I am working on related items 725, 739 and 747

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            Assignee:
            mikepersonick mikepersonick
            Reporter:
            jeremycarroll jeremycarroll
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              Created:
              Updated: