如何編寫Django模型以從多個表中獲取記錄？

Question

class Game(models.Model): 
    total_players = models.IntegerField(max_length=10) 
    created_on = models.DateTimeField(auto_now_add=True) 
    updated_on = models.DateTimeField(auto_now=True) 

class Players(models.Model): 
    game = models.ForeignKey(Game, related_name='players') 
    name = models.CharField(max_length=10, verbose_name="Player Name") 
    created_on = models.DateTimeField(auto_now_add=True) 
    updated_on = models.DateTimeField(auto_now=True) 

class Score(models.Model): 
    game = models.ForeignKey(Game) 
    name = models.ForeignKey(Players, related_name='scores') 
    score = models.IntegerField(max_length=10) 
    created_on = models.DateTimeField(auto_now_add=True) 
    updated_on = models.DateTimeField(auto_now=True) 

如何用Django模型編寫此查詢？

select p.name, sum(s.score) as total_score 
from game g, players p, score s 
where g.id=17 and g.id = p.game_id and p.id = s.name_id 
group by p.name 

非常感謝您的幫助提前。

Answer 1

我會試試這個，但我不確定是否會適當地過濾每個玩家的分數。我不認爲你們的關係是完全正常化的 - 如果Score對於Players是多對一，並且Players與Game多對一，則通常不會將game作爲Score上的獨立FK進行跟蹤。每個Players排是否真的只存在於單一遊戲中？

from django.db.models import Sum 
Game.objects.filter(id=17).values(players__name).annotate(total_score=Sum(players__scores_score))