题解 | #牛客直播转换率#
牛客直播转换率
http://www.nowcoder.com/practice/73bf143cfc7f452a8569c6d7eca380f9
select c.course_id, c.course_name, round(100* sum(if_sign) / sum(if_vw),2) as 'sign_rate(%)' from course_tb c left join behavior_tb b using(course_id) group by c.course_id, c.course_name