#2주차 강의
select name, count(*) from users
group by name;
select week, count(*) from checkins
group by week ;
select week, count(*) from checkins
where week = 1 ;
select week, min(likes) from checkins
group by week
;
select week, max(likes) from checkins
group by week
;
select week, round(avg(likes),1) from checkins
group by week
;
select week, sum(likes) from checkins
group by week
;
select * from checkins c
where week = 3
;
select payment_method, count(*) from orders
where course_title = "웹개발 종합반"
group by payment_method
order by count(*) desc
;
select payment_method, count(*) from orders
group by payment_method
order by count(*) desc
;
select * from users
-- order by email;
order by created_at desc
;
#quis1
select payment_method, count(*) from orders
where course_title = "앱개발 종합반"
group by payment_method
order by count(*) desc
;
#quis2
select * from users ;
select name, count(*) from users
where email like '%@gmail.com'
group by name
;
#quis3
select * from courses ;
select * from checkins ;
select course_id, round(AVG(likes),1) from checkins
group by course_id
;
#과제
select * from orders limit 10
;
select payment_method, count(*) from orders o
where o.email like '%@naver.com' and o.course_title = '앱개발 종합반'
group by payment_method
;