题解 | #计算25岁以上和以下的用户数量#
计算25岁以上和以下的用户数量
http://www.nowcoder.com/practice/30f9f470390a4a8a8dd3b8e1f8c7a9fa
select "25岁以下" as age_cut ,
count(device_id) as number
from user_profile
where age < 25 or age is null
union all
select "25岁及以上" as age_cut ,
count(device_id) as number
from user_profile
where age>=25
count(device_id) as number
from user_profile
where age < 25 or age is null
union all
select "25岁及以上" as age_cut ,
count(device_id) as number
from user_profile
where age>=25
