用个子查询。
select max(rate) rate,zone_name from table group by zone_name;
求出区域里最大的值。
然后把查询连在主表里。
直接求value就好了。
select *,a.rate/b.rate*10 as v from table a left join (select max(rate) rate,zone_name from
table group by zone_name) b on a.zone_name = b.zone_name;