selected_related()없어도 필요하면 join한다.py

# 1-1 이 QuerySet은 select_related()사용하지 않았어도 
# 필요한 조건을 inner join으로 해결하고 있다
# ORM이 이렇게 똑똑합니다...
(OrderedProduct.objects
 .filter(id=1, related_order__descriptions='sdfsdf')
 #.select_related('related_order'))
"""
SELECT *
    FROM "orm_practice_app_orderedproduct" 
    INNER JOIN "orm_practice_app_order" 
        ON ("orm_practice_app_orderedproduct"."related_order_id" = "orm_practice_app_order"."id")
    WHERE ("orm_practice_app_orderedproduct"."id" = 1 AND "orm_practice_app_order"."descriptions" = '주문의 상세내용입니다...1')
"""