select 地域,qq号,max(总信息量) from
(select a.qq号 , a.地域, sum(b.msg) as \'总信息量\'
from table_user a left join table_act b
        on a.qq号=b.qq  and  a.日期=b.ftime
        group by a.qq号
    order by 总信息量 desc) a
group by 地域;