题解 | 最大连续回答问题天数大于等于3天的用户

# 字段：author_id，author_level,days_cnt

# tb1：过程表，链接
with tb1 as(
    select answer_date,author_id,author_level
    from answer_tb left join author_tb using(author_id)
),

# tb2：排序
tb2 as(
    select author_id,author_level,dense_rank()over(partition by author_id order by answer_date) as cnt
    from tb1
)

# tb3：结果表筛选天数大于等于3
select author_id,author_level,max(cnt) as days_cnt
from tb2 
group by author_id,author_level
having max(cnt) >= 3