题解 | #计算25岁以上和以下的用户数量#

select CASE
WHEN age < 25 or age is null THEN '25岁以下'
WHEN age >= 25 THEN '25岁及以上'
end age_cut,count(1) AS number
FROM user_profile
group by age_cut

需求分析:求分段区间内数据的条数 查询列分别为age_cut,number 新建列

解题思路:case when age>=25 then '25岁及以上' case when age<25 or age is null then '25岁以下'

end age_cut,count(1) number ----> 以age_cut,number为输出

group by age_cut -----> 最后分组