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  1. Blazegraph (by SYSTAP)
  2. BLZG-963

BIND is leaving a variable unbound

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    Details

    • Type: Bug
    • Status: Closed - Won't Fix
    • Resolution: Cannot Reproduce
    • Affects Version/s: BIGDATA_RELEASE_1_2_4
    • Fix Version/s: None
    • Component/s: B+Tree
    • Labels:

      Description

      I am running into a bug when trying to BIND a variable:

      SELECT *
      WHERE {

      GRAPH ?g {

      BIND( "hello " as ?hello ) .
      BIND( CONCAT(?hello, "world") as ?helloWorld ) .
      ?member a ?class .
      }
      }
      LIMIT 1

      The first BIND works fine, but the second gives an unbound variable for ?helloWorld. See attached screenshot or xml. The query explanation and analysis is also attached.

      Oddly, if I put "hello " directly in the second BIND, instead of using the first BIND, then it works fine. It also works if I don't nest everything inside the GRAPH statement. And it works if I get rid of the "?member a ?class ." statement. But somehow the combination is triggering it.

      We're using BIGDATA_RELEASE_1_2_4.

      -----------------------------------------------

      Here is another example that illustrates the bug. Using this data:

      PREFIX tmp: <http://example/tmp/>
      INSERT DATA {

      GRAPH tmp: {

      tmp:s tmp tmp:v .
      }
      }

      The query:

      PREFIX tmp: <http://example/tmp/>
      SELECT *
      WHERE {

      GRAPH tmp: {

      #{ SELECT * {
      BIND( "hello " as ?hello ) .
      BIND( CONCAT(?hello, "world") as ?helloWorld ) .
      #}}
      ?s ?p ?v .
      }
      }

      leaves ?helloWorld unbound. But if I use a nested SELECT, by uncommenting the lines shown, it works properly. I'll also attach the query analysis with and without the nested SELECT.

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            Assignee:
            thompsonbry thompsonbry
            Reporter:
            davidbooth davidbooth
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              Created:
              Updated:
              Resolved: