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# -*- coding: utf-8 -*-
"""
14. Using a custom primary key
By default, Django adds an ``"id"`` field to each model. But you can override
this behavior by explicitly adding ``primary_key=True`` to a field.
"""
from __future__ import unicode_literals
from django.db import models
from .fields import MyAutoField
from django.utils.encoding import python_2_unicode_compatible
@python_2_unicode_compatible
class Employee(models.Model):
employee_code = models.IntegerField(primary_key=True, db_column='code')
first_name = models.CharField(max_length=20)
last_name = models.CharField(max_length=20)
class Meta:
ordering = ('last_name', 'first_name')
def __str__(self):
return "%s %s" % (self.first_name, self.last_name)
@python_2_unicode_compatible
class Business(models.Model):
name = models.CharField(max_length=20, primary_key=True)
employees = models.ManyToManyField(Employee)
class Meta:
verbose_name_plural = 'businesses'
def __str__(self):
return self.name
@python_2_unicode_compatible
class Bar(models.Model):
id = MyAutoField(primary_key=True, db_index=True)
def __str__(self):
return repr(self.pk)
class Foo(models.Model):
bar = models.ForeignKey(Bar)
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