题解 | #查看不同年龄段的用户明细#

select
    device_id,
    gender,
    case
        when age >= 25 then '25岁及以上' 
        #繁杂的写法
        # when (age >= 20 and age <= 24) then '20-24岁'
        #简便的写法
        when age >= 20 then '20-24岁'
        when age < 20 then '20岁以下'
    else '其他'
    end as age_cut
from
    user_profile

select

case when <condition> then <result>

case when <condition> then <result>

end