title: Can not bind parameter to CDbCommand
body: <p>say, i am going to follow the good practice of avoiding sql injection. so this is not good:</p>
  
  <pre><code>      $query="SELECT id,tag  FROM tbl_tags WHERE tag LIKE '%".$tag."%' ORDER BY creation_time DESC LIMIT 0,10 ";
  </code></pre>
  
  <p>in stead i have to use parameter binding:</p>
  
  <pre><code>     $query="SELECT id,tag  FROM tbl_tags WHERE tag LIKE :tag ORDER BY creation_time DESC LIMIT 0,10 ";
       $command =Yii::app()-&gt;db-&gt;createCommand($query);
   $command-&gt;bindParam(":tag", "%{$tag}%", PDO::PARAM_STR);
       $models = $command-&gt;queryAll();
  </code></pre>
  
  <p>But this generates: Fatal error:  Cannot pass parameter 2 by reference</p>
  
  <p>How can i bind this LIKE oriented parameter ?</p>