题解 | SQL啰嗦了点，但是容易看懂
某乎问答回答过教育类问题的用户里有多少用户回答过职场类问题
https://www.nowcoder.com/practice/b02cf9ee7b9f4cdda308f8155ff3415d
select count(distinct ab.author_id) from answer_tb ab left join issue_tb i on ab.issue_id=i.issue_id where i.issue_type="Career" and ab.author_id in ( select ab.author_id from answer_tb ab left join issue_tb i on ab.issue_id=i.issue_id where issue_type="Education" )
顺丰集团工作强度 372人发布