blob: a6db9425bd408a9ac1d416d0366fe2b12bb9ed4b (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
|
"""
Multiple many-to-many relationships between the same two tables
In this example, an ``Article`` can have many "primary" ``Category`` objects
and many "secondary" ``Category`` objects.
Set ``related_name`` to designate what the reverse relationship is called.
"""
from django.db import models
from django.utils.encoding import python_2_unicode_compatible
@python_2_unicode_compatible
class Category(models.Model):
name = models.CharField(max_length=20)
class Meta:
ordering = ('name',)
def __str__(self):
return self.name
@python_2_unicode_compatible
class Article(models.Model):
headline = models.CharField(max_length=50)
pub_date = models.DateTimeField()
primary_categories = models.ManyToManyField(Category, related_name='primary_article_set')
secondary_categories = models.ManyToManyField(Category, related_name='secondary_article_set')
class Meta:
ordering = ('pub_date',)
def __str__(self):
return self.headline
|