题解 | 查看不同年龄段的用户明细
查看不同年龄段的用户明细
https://www.nowcoder.com/practice/ae44b2b78525417b8b2fc2075b557592
#一种新思路，分类之后再嵌套排序
select device_id,gender,age_cut from
(select id,device_id,gender,'其他' as age_cut
from user_profile
where age is null
union all
select id,device_id,gender,'20-24岁' as age_cut
from user_profile
where age>=20 and age<=24
union all
select id,device_id,gender,'25岁及以上' as age_cut
from user_profile
where age>=25 ) as t
order by id
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