public function delete($id, $rev)
  {
    if(!$this->db) {
      throw new SagException('No database specified');
    }

    if(!is_string($id) || !is_string($rev) || empty($id) || empty($rev)) {
      throw new SagException('delete() expects two strings.');
    }

    $url = "/{$this->db}/$id";

    if($this->cache) {
      $this->cache->remove($url);
    }

    return $this->procPacket('DELETE', $url.'?rev='.urlencode($rev));
  }