select distinct a.name from table a left join (select distinct name from table where fenshu <= 80) b on a.name=b.name where b.name is null;

select name from table where fenshu > 80 group by name having cnt > 0;

select distinct name from table where name in (select distinct name from table where fenshu > 80)

select name,sum(case when fenshu<=80 then 1 else 0 end) scr from table group by name having scr=0;