title: How to make this query in Zend DB?
body: <p>I'm trying to have Zend DB generate the following query:</p>
  
  <pre><code>SELECT DISTINCT
      US.nombre AS Cliente,
      VE.id_venta,
      VE.fecha,
      VE.total,
      ve.observacion
  FROM
      usuarios AS US,
      ventas AS VE
  </code></pre>
  
  <p>I have tried the code below, but it does not work:</p>
  
  <pre><code>$select = $this-&gt;select();
  $select-&gt;from(array('VE' =&gt; 'ventas'), array('id_venta', 'fecha', 'total', 'observacion'))
         -&gt;from(array('US' =&gt; 'usuarios'),'ve.id_usuario');
  </code></pre>