* 겪고 있는 문제 상황을 최대한 자세하게 작성해주세요.

* 문제 해결을 위해 어떤 시도를 해보았는지 구체적으로 함께 알려주세요.

with 절 연습하기 입니다 결과물이 틀리게 나와요 확인부탁

with table1 as (

select course_id, count(distinct(user_id)) as cnt_checkins from checkins

group by course_id

), table2 as (

select course_id, count(*) as cnt_total from orders

group by course_id

)

select c.title,

a.cnt_checkins,

b.cnt_total,

(a.cnt_checkins/b.cnt_total) as ratio

from table1 a inner join table2 b on a.course_id = b.course_id

inner join courses c on a.course_id = c.course_id