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    Details

    • Type: Bug
    • Status: Open
    • Priority: High
    • Resolution: Unresolved
    • Affects Version/s: None
    • Fix Version/s: None
    • Component/s: Bigdata RDF Database
    • Labels:
      None

      Description

      I have this model in the database (it's an example)

      [] a qb:Observation;
      vocab:predicate0 "foo" ;
      vocab:predicate1 "bar";
      .
      .
      vocab:predicate36 "another";

      We have 37 predicates and we are doing this query

      SELECT ?object0 ?object1 .... ?object36
      WHERE {
      hint:Query hint:maxParallel 30 .
      GRAPH <http://datos.mineduc.cl/MATRI-UNICA-2006>

      { ?obs a qb:Observation vocab:predicate0 ?object0; vocab:predicate1 ?object1; . . vocab:predicate36 ?object36 }

      }

      This query is taking 10 minutes to complete and the answer is around 4 millon rows.

      On the other side we are doing the count (aggregated) query and it's taking less than a minute

      SELECT COUNT(?obs) ?total
      WHERE {
      hint:Query hint:maxParallel 30 .
      GRAPH <http://datos.mineduc.cl/MATRI-UNICA-2006>

      { ?obs a qb:Observation vocab:predicate0 ?object0; vocab:predicate1 ?object1; . . vocab:predicate36 ?object36 }

      }

      We have this doubt.... It's normal such difference in time between the agreggate query and the disaggregated one?

      Or there is something we can do to have a better performance in the dessagregated query?

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            Assignee:
            beebs Brad Bebee
            Reporter:
            birdman Javier Pajaro
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              Created:
              Updated: