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這里先來借用一個書本(book)的數據模型作為例子：

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									from django.db import models

									class Publisher(models.Model):

									  name = models.CharField(max_length=30)

									  address = models.CharField(max_length=50)

									  city = models.CharField(max_length=60)

									  state_province = models.CharField(max_length=30)

									  country = models.CharField(max_length=50)

									  website = models.URLField()

									  def __unicode__(self):

									    return self.name

									class Author(models.Model):

									  first_name = models.CharField(max_length=30)

									  last_name = models.CharField(max_length=40)

									  email = models.EmailField()

									  def __unicode__(self):

									    return u'%s %s' % (self.first_name, self.last_name)

									class Book(models.Model):

									  title = models.CharField(max_length=100)

									  authors = models.ManyToManyField(Author)

									  publisher = models.ForeignKey(Publisher)

									  publication_date = models.DateField()

									  def __unicode__(self):

									    return self.title

訪問多對多值(Many-to-Many Values)

多對多和外鍵工作方式相同，只不過我們處理的是QuerySet而不是模型實例。例如,這里是如何查看書籍的作者：

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									>>> b = Book.objects.get(id=50)

									>>> b.authors.all()

									[<Author: Adrian Holovaty>, <Author: Jacob Kaplan-Moss>]

									>>> b.authors.filter(first_name='Adrian')

									[<Author: Adrian Holovaty>]

									>>> b.authors.filter(first_name='Adam')

									[]

反向查詢也可以。要查看一個作者的所有書籍,使用author.book_set ,就如這樣:

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									>>> a = Author.objects.get(first_name='Adrian', last_name='Holovaty')

									>>> a.book_set.all()

									[<Book: The Django Book>, <Book: Adrian's Other Book>]