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  1. Apache Jena
  2. JENA-1522

Unable to consistently retrieve data from large dataset

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    Details

    • Type: Bug
    • Status: Closed
    • Priority: Critical
    • Resolution: Duplicate
    • Affects Version/s: Jena 3.6.0
    • Fix Version/s: None
    • Component/s: Fuseki, Jena
    • Labels:
      None
    • Environment:

      System 1:  Centos 7, Jena 3.6, Unknown Fuseki version.

      System 2:  Ubuntu 16.04 running Docker.  Running stain/jena-fuseki from the official Docker Hub.

       

      Description

      In my 500M+ triple dataset, queries seem to be failing for no clear reason. Here's an example.

      prefix Products: <http://www.example.com/test/Products#> 
      select ?p ?o 
      where { 
          Products:ABC ?p ?o . 
      }
      

      ...results in a list like:

      Products:HasComponent Products:DEF 
      Products:HasComponent Products:GHI 

      Now running this query:

      prefix Products: <http://www.example.com/test/Products#> 
      select ?p 
      where { 
          Products:ABC ?p Products:DEF . 
      } 

      ...has no results. How is this possible?

       

      Here's another example.

      prefix Products: <http://www.example.com/test/Products#> 
      ask where { 
          Products:ABC Products:PartNumber ?p . 
          filter ( ?p = "ABC" ) 
      } 

      This returns "True"

       

      prefix Products: <http://www.example.com/test/Products#> 
      ask where { 
          ?s Products:PartNumber ?p . 
          filter ( ?p = "ABC" ) 
      } 

      This returns "False"

       

      What other info can I provide?

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              • Assignee:
                Unassigned
                Reporter:
                bmullen Brian Mullen
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                • Created:
                  Updated:
                  Resolved: