jena-arq/testing/ARQ/Optional/opt-04.rq - jena - Git at Google

 PREFIX  foaf:   <http://xmlns.com/foaf/0.1/>

 SELECT *
    {
      OPTIONAL { ?x foaf:nick  ?nick }
    }
	PREFIX foaf: <http://xmlns.com/foaf/0.1/>

	SELECT *
	{
	OPTIONAL { ?x foaf:nick ?nick }
	}