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from django.contrib.auth.models import User
from django.db import models
# Forward declared intermediate model
class Membership(models.Model):
person = models.ForeignKey("Person", models.CASCADE)
group = models.ForeignKey("Group", models.CASCADE)
price = models.IntegerField(default=100)
# using custom id column to test ticket #11107
class UserMembership(models.Model):
id = models.AutoField(db_column="usermembership_id", primary_key=True)
user = models.ForeignKey(User, models.CASCADE)
group = models.ForeignKey("Group", models.CASCADE)
price = models.IntegerField(default=100)
class Person(models.Model):
name = models.CharField(max_length=128)
def __str__(self):
return self.name
class Group(models.Model):
name = models.CharField(max_length=128)
# Membership object defined as a class
members = models.ManyToManyField(Person, through=Membership)
user_members = models.ManyToManyField(User, through="UserMembership")
def __str__(self):
return self.name
# Using to_field on the through model
class Car(models.Model):
make = models.CharField(max_length=20, unique=True, null=True)
drivers = models.ManyToManyField("Driver", through="CarDriver")
def __str__(self):
return str(self.make)
class Driver(models.Model):
name = models.CharField(max_length=20, unique=True, null=True)
class Meta:
ordering = ("name",)
def __str__(self):
return str(self.name)
class CarDriver(models.Model):
car = models.ForeignKey("Car", models.CASCADE, to_field="make")
driver = models.ForeignKey("Driver", models.CASCADE, to_field="name")
def __str__(self):
return "pk=%s car=%s driver=%s" % (str(self.pk), self.car, self.driver)
# Through models using multi-table inheritance
class Event(models.Model):
name = models.CharField(max_length=50, unique=True)
people = models.ManyToManyField("Person", through="IndividualCompetitor")
special_people = models.ManyToManyField(
"Person",
through="ProxiedIndividualCompetitor",
related_name="special_event_set",
)
teams = models.ManyToManyField("Group", through="CompetingTeam")
class Competitor(models.Model):
event = models.ForeignKey(Event, models.CASCADE)
class IndividualCompetitor(Competitor):
person = models.ForeignKey(Person, models.CASCADE)
class CompetingTeam(Competitor):
team = models.ForeignKey(Group, models.CASCADE)
class ProxiedIndividualCompetitor(IndividualCompetitor):
class Meta:
proxy = True
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