title: Why does my SPARQL query duplicate results?
body: <p>I am doing some searching, and learning more about SPARQL, but it is not easy like SQL. I just want to know why my query duplicates result and how to fix it.  This is my SPARQL Query: </p>
  
  <pre class="lang-none prettyprint-override"><code>PREFIX OQ:&lt;http://www.owl-ontologies.com/Ontology1364995044.owl#&gt;
  
  SELECT ?x ?ys ?z ?Souhaite
  WHERE {
    ?y OQ:hasnameactivite ?x.
    ?y OQ:AttenduActivite ?Souhaite.
    ?y OQ:SavoirDeActivite ?z.
    ?y OQ:hasnamephase ?ys.
    ?y OQ:Activitepour ?v.
    ?ro OQ:hasnamerole ?nr.
    ?y OQ:avoirrole ?ro.
    FILTER regex (?nr ,"Concepteur").
    FILTER regex (?v,"Voiture").
  }
  </code></pre>
  
  <p>This gives me these results:</p>
  
  <p><img src="https://i.stack.imgur.com/O6xkv.png" alt="enter image description here"></p>
  
  <p>Expected result is:</p>
  
  <p><img src="https://i.stack.imgur.com/bqvsD.png" alt="enter image description here"></p>