题解 | #某乎问答高质量的回答中用户属于各级别的数量#
某乎问答高质量的回答中用户属于各级别的数量
http://www.nowcoder.com/practice/69c85db3e59245efb7cee51996fe2273
select case when author_level between 5 and 6 then '5-6级'
when author_level between 3 and 4 then '3-4级'
else '1-2级' end
as level_cut,
count(case when char_len >= 100 then issue_id else null end) as 高质量评论数
from author_tb join answer_tb on author_tb.author_id = answer_tb.author_id
group by level_cut
having 高质量评论数 > 0
order by 高质量评论数 desc;
