题解 | #小破站9月上中下旬的用户充值数量#

select seg_date,count(seg_date)
from 
(
 select case when begin_date between '2021-09-01' and '2021-09-10'
             then  '上旬'
             when begin_date between '2021-09-11' and '2021-09-20'
             then  '中旬'
              when begin_date between '2021-09-21' and '2021-09-30'
              then '下旬'
              end  as seg_date
 from detail_list_tb
) as t
where seg_date is not null
group by seg_date