$users =
            (new User())->alias('u')->join('pusher p', 'u.id=p.user_id')
                ->where("u.parents_id", $user_id)
                ->where("p.level", ">=",2)
            ->order("u.create_time desc")->field("u.id,u.avatar,u.nickname,u.phone,p.level")->limit(5)->select();