擅长:python、mysql、java
<p>给他们起相关的名字(更容易管理):</p>
<pre><code>class Topic(models.model)
user = models.ForeignKey(UserProfile, related_name = 'topics')
lists = models.ManyToManyField(List, related_name = 'topics')
class List(models.model)
activities = models.ManyToManyField(Activity, related_name = 'lists')
class Activity(models.model)
activity = models.CharField(max_length=250)
</code></pre>
<p>然后你可以做一些很棒的事情:</p>
<pre><code>user = UserProfile.objects.get(pk=1) # for example
user.topics.all() # returns all topics
topic = Topic.objects.get(pk=1) # for example
topic.users.get(pk=1) # returns user
lists = topic.lists.all() # returns List object instances QuerySet
for list in lists:
list.activites.all()
</code></pre>
<p>便利信息:<a href="https://docs.djangoproject.com/en/dev/ref/models/relations/" rel="nofollow">https://docs.djangoproject.com/en/dev/ref/models/relations/</a></p>