Ordenar por distancia Ordenar consulta mysql

if (!empty($sortBy)) {
            if ($sortBy == 'distance') {
                $orderSql = "(abs(e.longitude - $centerLongitude) + abs(e.latitude - $centerLatitude)) ASC ";
                $orderSql = "e.distance ASC ";
            } else if ($sortBy == 'edittime') {
                $orderSql = "e.edittime DESC ";
            } else if ($sortBy == 'addtime') {
                $orderSql = 'e.addtime DESC ';
            }
        }

SELECT e.ID , e.title, e.userid, e.longitude, e.latitude, e.cat2icon, e.groupid, e.firmname, e.contact, e.addtime, e.salemodel, e.address, e .pic, e.isvip, ST_Distance (punto (e.longitude, e.latitude), punto (117.29397231570944,34.20784829452513)) * 111195 como distancia de tp_equipment eDONDE e. isdel= '0' y e. authstatusIN ( '1', '0') y e. titleLIKE '%车%' ORDER BY DESC ISVIP, ASC distancia, addTime LIMIT DESC 0,20