with table1 as (

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

   group by course_id),table2 b 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

inner join table2 on a.course_id = b.course_id

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

라고 적으니

Table 'sparta.table1' doesn't exist

라는 결과가 계속 나옵니다 ㅠㅠ