How can I retrieve a list of field for all objects in Django?

Question

I want to retrieve a list of all of the values for one field from a query in django. For example, I have a query of users, but rather than a queryset (or list) of user objects, I want a list just the usernames (strings). In a sense this is asking to restrict only to one column of data.

Answer 1

Have you tried

list(User.objects.all().values_list('username', flat=True))  

If you only pass in a single field, you can also pass in the flat parameter. If True, this will mean the returned results are single values, rather than one-tuples. Additionally, casting it to a list makes the returned value a list instead of a queryset

Answer 2

To get the list of usernames:

>>> User.objects.all().values('username') >>> [{'username': u'u1'}, {'username': u'u2'}]  >>> User.objects.all().values_list('username') >>> [(u'u1',), (u'u2',)] 

If you want just strings, a list comprehension can do the trick:

>>> usr_names = User.objects.all().values('username') >>> [u['username'] for u in usr_names] >>> [u'u1', u'u2'] 

Using values_list:

>>> usr_names = User.objects.all().values_list('username') >>> [u[0] for u in usr_names] >>> [u'u1', u'u2']