* 겪고 있는 문제 상황을 최대한 자세하게 작성해주세요.

* 문제 해결을 위해 어떤 시도를 해보았는지 구체적으로 함께 알려주세요.

따라했는데 계속 오류가 납니다.

어떤 오류인가요?

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

SQL Error [1146] [42S02]: Table 'sparta.table1' doesn't exist