sql语句 用户一天的数据，取最大的一条，再统计

 

统计今天升级角色个数，如果用户一天升级了多条，只统计最后一次升级的角色个数

select mid,count(*) from (

select uid ,max(updaterankid) as mid from bp_trade01
WHERE
payType = 'APP-U' 
and   ddCreateDate = '2017-06-28'   
GROUP BY
uid
) as a
GROUP BY
mid