title: How to select the one equals to each others in Sparql
body: <p>For example,there is one simple select sparql query:  </p>
  
  <pre><code>SELECT *  Where  
  {
    CT:A skos:broader ?A.  
    CT:B skos:broader ?B.  
    FILTER(?A=?B)  
  } 
  </code></pre>
  
  <p>With the <code>FILTER</code>,it is easy to select the objects that equal to each others.
  But when there are even more triples to match ,for example,from <code>CT:A skos:broader ?A</code> to <code>CT:Z skos:broader ?Z</code>,how can I filter those meet <code>?A=?B=?C=....?Z?</code><br>
  Wish to make it clear.</p>