query: #title: Qualifier for property constraint (P2302)
  # Complex constraint from [[Property talk:P9729]]
  # This qualifier is generally used only on [[Property:P2302|property constraint&#32;<small dir="ltr">(P2302)</small>]] and [[Property:P2271|Wikidata property example for properties&#32;<small dir="ltr">(P2271)</small>]]. TODO: double-check
  SELECT ?item ?property
  {
      ?prop pq:P9729 ?qualifierP9729value .
      hint:Query hint:optimizer "None" .
      ?item ?p ?prop .
      ?property wikibase:claim ?p .
      ?property wikibase:statementProperty ?ps .
      ?prop ?ps ?value .
      FILTER( ?property != wd:P2302 ) 
      FILTER( ?property != wd:P2271 ) 
  }