Laravel join时报错iStatus not found解决方法

$gold = DB::connection('con')->table('user as u')
            ->leftJoin('report as r','u.iAutoID', '=', 'r.iUserID')
            ->select('u.name', 'r.html')
            //->get();
            ->toSql();
        //select `u`.`name`, `r`.`html` from `user` as `u` left join `report` as `r` on `u`.`iAutoID` = `r`.`iUserID`