[JENA-2280] Invalid results of SPARQL query with a federated subquery

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: Jena 4.3.1, Jena 4.3.2, Jena 4.4.0
• Fix Version/s: Jena 4.5.0
• Component/s: Fuseki
• Assignee: Andy Seaborne
• Reporter: Michal Pietrusinski
• Created: 10/Feb/22 14:40
• Updated: 04/May/22 21:21
• Resolved: 12/Feb/22 12:39

Description

In Fuseki I created on dataset named "test".

The following query gives 1 result with an empty string, whereas the expected value is "test"

SELECT ?temp
WHERE {
  {
    SELECT (?value as ?temp) {
      { SERVICE <http://localhost:3030/test/query> {          
          VALUES ?value { "test" }  
        }
      }
    }    
  }  
}

However the following query returns the correct result "test".

SELECT *
WHERE {
  {
    SELECT (?value as ?temp) {
      { SERVICE <http://localhost:3030/test/query> {          
          VALUES ?value { "test" }  
        }
      }
    }    
  }  
}

Both of these queries work fine on an older Fuseki release 4.1.0

Issue Links

• links to: GitHub Pull Request #1195
• links to: GitHub Pull Request #1197