안녕하세요,

강의중에 아래 두개의 테이블을 inner join 하셨는데요.

select c.user_id, round(AVG(likes), 1) as avg_likes from checkins c 

group by c.user_id 

SELECT pu.user_id, pu.point from point_users pu

아래처럼 하면 정상적으로 결과를 보여주는데,

# 1>2

SELECT pu.user_id, pu.point, a.avg_likes from point_users pu
inner join (

select c.user_id, round(AVG(likes), 1) as avg_likes from checkins c 
group by c.user_id 

) a on pu.user_id = a.user_id 

순서를 반대로 하면 에러값이 뜹니다. Inner join은 순서에 민감하지 않는 걸로 알고있는데 아닌가요?

select c.user_id, round(AVG(c.likes), 1) as avg_likes from checkins c 
group by c.user_id 
inner join (

SELECT pu.user_id, pu.point from point_users pu

) a on c.user_id = a.user_id

어디를 수정해야할까요?