/**
  * Enables calling the various parts of a query as functions for a fluent interface.
  * 
  * i.e. $query->select("id")->from("mytable")->orderby("name"); 
  * See DatabaseSelectQuery class for an example. 
  *
  */
 public function __call($method, $args)
 {
     if (!$this->has($method)) {
         return parent::__call($method, $args);
     }
     $curValue = $this->get($method);
     $value = $args[0];
     if (is_array($value)) {
         $curValue = array_merge($curValue, $value);
     } else {
         $curValue[] = trim($value, ", ");
     }
     $this->set($method, $curValue);
     return $this;
 }