题解 | 最长连续登录天数

with t1 as (
    select distinct(user_id),rank() over(partition by user_id order by fdate) as ranking,fdate
    from tb_dau
    where fdate between '2023-01-01' and '2023-02-01'
),
t2 as (
    select user_id,rank() over(partition by user_id,tag order by fdate) as max_consec_days
    from(
        select user_id,adddate(fdate,INTERVAL-ranking day) as tag,fdate
        from t1 
    ) t3
)
select user_id,max(max_consec_days) as max_consec_days
from t2 
group by user_id