题解 | 某乎问答最大连续回答问题天数大于等于3天的用户及其对应等级

with temp as
(
    select author_id,date_sub(answer_date,interval rk day) as time,count(*) as days_cnt from 
(
    select distinct author_id,answer_date,dense_rank() over(partition by author_id order by answer_date) as rk from answer_tb
    )t
group by author_id,time
)
select tp.author_id,author_level,days_cnt from temp tp join author_tb a using(author_id) where days_cnt >= 3;