select at.author_id,
author_level,
max(cnt) as days_cnt 
from(
select author_id,count(primary_date) as cnt
from(
select 
author_id,
date_sub(answer_date,interval row_number() over(partition by author_id order by answer_date) day) as primary_date
from answer_tb
)a

group by author_id,primary_date)b

join author_tb at
on b.author_id = at.author_id
group by at.author_id,author_level
having days_cnt >=3

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