hitung hari pake pg

$date="2008-09-12";
function hithari($date){
     global $dbconn;
     $sql="select TIMESTAMP '$date'-CURRENT_DATE";
     $rs=pg_query($dbconn,$sql);
     $row=pg_fetch_array($rs);
     $d=str_replace("days","",$row[0]);
     $d=str_replace("day","",$d);
     $d=trim($d);
     return $d;
}

pake php langsung gmna ya????

bg83