Django / User access in ManyToMany field
django, many-to-many
Solution
Because the many-to-many relation is through the `members` property, and this property has the `related_name` attribute, the correct syntax is:
user_groups = user.member.all()
( Without the related name attribute, it would be `user_groups = user.members_set.all()` )
And the reverse relation is:
group_users = group.members.all()
Problem
I am making a django app using the `User` class from `django.contrib.auth.models`. I have defined a model, called a group with a M2M relationship to users. I have difficulty retrieving the groups a given user belongs to. Here's the group definition: ``` class group(models.Model): user = models.ForeignKey(User,related_name = 'owner') # the owner name = models.CharField(max_length=100) # name of the group # members of the group members = models.ManyToManyField(User,related_name = 'member') def __unicode__(self): return str(self.name) ``` I would like to retrieve the groups for which the user belongs to the members field of the groups. Here is the command that fails, trying to retrieve the groups that a particular user belongs to - I am not sure why - could you let me know ? (`user` is a `User` instance) ``` user_groups = user.group_set.all() ``` The error I get is: ``` 'User' object has no attribute 'group_set' ``` What's wrong here? SOLUTION I eventually found the solution. I had to make the query with the `related_name`, so here it is: ``` groups_member = user.member.all() ```