Php, join, order by

[quimfv]

Código MySQL:

$filtro="Select turf_carrr.*, turf_poscns.* from turf_poscns ".
            "LEFT JOIN turf_carrr ON turf_poscns.idcarrr=turf_carrr.idcarrr " .     
            "Where turf_poscns.idcabll='$idcabll' and turf_poscns.poscn !='0' ".
            "and turf_poscns.poscn !='00' and turf_poscns.poscn !='NC' ".
            "order by turf_poscns.idcarr desc ";
 

Ahora?