[SQL] 우유와 요거트가 담긴 장바구니

https://programmers.co.kr/learn/courses/30/lessons/62284?language=oracle 

코딩테스트 연습 - 우유와 요거트가 담긴 장바구니

 

select a.cart_id
from cart_products a, cart_products b
where a.cart_id = b.cart_id 
and a.name = 'Milk' 
and b.name = 'Yogurt'
group by a.cart_id
order by a.cart_id

 

뭐가 더 좋은건지 모르겠다

select cart_id
from cart_products
where name = 'Milk'
and cart_id in 
(
select cart_id
    from cart_products
    where name = 'Yogurt'
)
group by cart_id
order by cart_id