Django-如何链接表

艾伦·廷吉(Alan Tingey)

您好,stackoverflow小组,

我有以下两个Django表:

class StraightredFixture(models.Model):
    fixtureid = models.IntegerField(primary_key=True)
    soccerseason = models.IntegerField(db_column='soccerSeason')  # Field name made lowercase.
    hometeamid = models.IntegerField()
    awayteamid = models.IntegerField()
    fixturedate = models.DateTimeField()
    fixturestatus = models.CharField(max_length=24)
    fixturematchday = models.IntegerField()
    hometeamscore = models.IntegerField()
    awayteamscore = models.IntegerField()

    class Meta:
        managed = False
        db_table = 'straightred_fixture'

class StraightredTeam(models.Model):
    teamid = models.IntegerField(primary_key=True)
    teamname = models.CharField(max_length=36)
    teamcode = models.CharField(max_length=5)
    teamshortname = models.CharField(max_length=24)

    class Meta:
        managed = False
        db_table = 'straightred_team'

在views.py中,我知道可以放入以下内容,并且可以正常运行:

def test(request):
    fixture = StraightredFixture.objects.get(fixtureid=136697)
    return render(request,'straightred/test.html',{'name':fixture.hometeamid})

如上所述,这一切都很好,但是我希望返回可在StraightredTeam模型中找到的hometeamid的团队名称。

经过一番环顾后,我被推向“ select_related”的方向,但是我不清楚如何在现有表中实现它,以及对于这种类型的查询,这是否是最有效的方法还不清楚。感觉不错。

请注意,此代码是使用“ python manage.py inspectdb”创建的。

在此阶段的任何建议将不胜感激。非常感谢,艾伦。

奥姆

请参阅模型关系

Django提供了特殊的模型字段来管理表关系。满足您需求的一个是ForeignKey

而不是声明:

hometeamid = models.IntegerField()
awayteamid = models.IntegerField()

我猜这是的结果python manage.py inspectdb,您将声明:

home_team = models.ForeignKey('<app_name>. StraightredTeam', db_column='hometeamid', related_name='home_fixtures')
away_team = models.ForeignKey('<app_name>. StraightredTeam', db_column='awayteamid', related_name='away_fixtures')

通过执行此操作,您将告诉Django ORM处理内部关系,这将使您能够执行以下操作:

fixture = StraightredFixture.objects.get(fixtureid=some_fixture_id)
fixture.home_team  # Returns the associated StraightredTeam instance.

team = StraightredTeam.objects.get(team_id=some_team_id)
team.home_fixtures.all()  # Return all at home fixtures for that team.

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