public function build()
 {
     $build = parent::build();
     if ($this->count !== TRUE) {
         $build['$limits'] = $this->limits();
     }
     return array_filter($build);
 }
 public function build()
 {
     $build = parent::build();
     if (isset($this->order)) {
         $build += array('$order' => $this->order);
     }
     $parameters = $this->parameters();
     if (isset($parameters)) {
         $build += $parameters->build();
     }
     return $build;
 }