public function read()
{
    return $this->db->select("
        a.*,b.*,c.*,d.*")
    ->from("trip AS a")
    ->join('fleet_type AS b', 'a.type = b.id')
    ->join('trip_route AS c', 'a.route = c.id')
    ->join('shedule AS d', 'a.shedule_id = d.shedule_id')
    ->limit($limit, $start)
    ->get()
    ->result();
      }