Getting values correctly while using Many to Many relation - django

Question

I have standart User model and Categories model like this;
class Categories(models.Model):
name=models.CharField(max_length=100)
def __str__(self):
return self.name
And here is another class for relation which associates some users with some categories;
class Interested(models.Model):
user = models.ManyToManyField(User)
category = models.ManyToManyField(Categories)
For example if I have Users such as Bob, Eric, Oliver, Michael
and categories such as Basketball, Football
and relations like that
Bob -> Basketball,Football
Eric-> Basketball
Oliver -> Football
(michael not interested in anything)
I want to get list of who interested in what? How can I handle this? Thank you for your help.

Answer 1

You can get the instance of Interested for a user with:
interested = Interested.objects.get(user="your user")
and list the linked categorys by:
interested.category.all()
But I would, if not nescessary for any other reason, just link the category directly to the user....
class Category(models.Model):
name = models.Charfield()
user = models.ManyToManyField(user)
This way you can get the categorys for a user:
categorys = Category.objects.filter(user="youruser")
and if you pass this to your template just do:
{% for category in categorys %} {{ category.name }}{% endfor %}
To get the users interested in a category, just get the Category instance with:
category = Category.objects.get(name="categoryname")
and the the related user models with:
usersincategory = category.user.all()
if you want this for all categorys just use a normal for loop:
categorys = Category.objects.all()
for category in categorys:
category.user.all()