[오타 제보] 선행 데이터를 기반으로 한 데이터 분석

안녕하세요~!
강의에 오타가 있는 것 같아서 질문 드립니다.

e2 서브쿼리에 user_id도 select 절에 포함되야 할 것 같아요!

select sum(sign_up) as signed_up,
			sum(complete_purchase) as completed_purchase,
			(sum(complete_purchase) / sum(sign_up) * 100) as conversion_rate
from (
			-- 1월에 새로 가입한 유저 목록
			select user_id,
						 1 as sign_up,
						 min(created_at) as sign_up_time
			from user_events
			where event_type = 'SIGN_UP'
			and created_at >= '2024-01-01' and created_at < '2024-02-01'
			group by user_id
) e1 left join (
			-- 처음 결제한 시점 정보 목록
			select user_id, 
						 1 as complete_purchase,
						 min(created_at) as complete_purchase_time
			from user_events
			where event_type = 'COMPLETE_PURCHASE'
			group by user_id
) e2 on e2.user_id = e1.user_id
			and e2.complete_purchase_time >= e1.sign_up_time
			and e2.complete_purchase_time < date_add(e1.sign_up_time, interval 7 day);