题解 | #查看不同年龄段的用户明细#

select device_id,gender,age_cut
from(
select *,
case when age<20 then '20岁以下'
when age between 20 and 24 then'20-24岁'
when age>=25 then'25岁及以上'
when age is null then'其他'
end as age_cut
from user_profile
) as a;