Mysql start-complete

Hi all .

could someone please tell me if this is good code for mysql.

PHP Code:

function get_cities_from_id( $cityid )
    {
        $this->db->select( '
          app_cities.city_id,
          app_cities.city_fr ,
          app_cities.city_zip,
          app_cities.city_latitude,
          app_cities.city_longitude' );
        $this->db->from( 'app_cities' );
        $this->db->where( 'city_id', $cityid );
        $this->db->trans_start();
        $this->db->trans_complete();
        $result = $this->db->get();
        if ( $result->num_rows() > 0 ):
            return $result->first_row();
        else:
            return false;
        endif;
    } 


thanks alot.