mysql 表格处理-每个同一组别取出最大前3笔数据
如题，如何用mysql语法写出右图的效果
以组别为区分，分别区出金额前3名的资料
select *
from (
select a.组别,a.省份,a.金额,count(*) ct
from table a
left join table b
on a.组别=b.组别
where a.金额<=b.金额
group by a.组别,a.省份,a.金额
) t
where ct<=3
如题，如何用mysql语法写出右图的效果
以组别为区分，分别区出金额前3名的资料
select *
from (
select a.组别,a.省份,a.金额,count(*) ct
from table a
left join table b
on a.组别=b.组别
where a.金额<=b.金额
group by a.组别,a.省份,a.金额
) t
where ct<=3