题解 | #分群并计算群体人数#
分群并计算群体人数
https://www.nowcoder.com/practice/24319fd5c03e482c935783107114933d
select case when age <20 then '20以下' when age >=20 and age<=50 then '20-50' when age >50 then '50以上' else '未填写' end as age_group, count(*) user_count from customers_info group by age_group;
使用case。。when 语法进行划分范围,再使用group by对于划分的范围进行分组,统计个数得出结果