如何编写Django模型以从多个表中获取记录？

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)

How do I write this query with Django models?

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 

Thank you so much for your help in advance.

Answer 1

I'd try this, but I'm not sure offhand if it will appropriately filter the scores to those for each player. I don't think your relationships are fully normalized - if Score is many-to-one for Players , and Players is many-to-one with Game , you wouldn't normally track game as an independent FK on Score . Can each Players row really exist only for a single game?

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