Django model latest() method

Question

I am having the following issue (BTW I think I had not had this problem the day before):

>>> rule = Rule.objects.get(user=user)
>>> rule.id
1
>>> rule = Rule.objects.get(user=user).latest('id')

AttributeError: 'Rule' object has no attribute 'latest'

Why am I getting the error?

Answer 1

latest method belongs to QuerySet, not model.

Replace following line:

rule = Rule.objects.get(user=user).latest('id')

with:

rule = Rule.objects.filter(user=user).latest('id')

Answer 2

The get() function of the Model Manager returns an instance of the Model itself.

The latest() function you mention belongs to the QuerySet class. Calling .filter(), .all(), .exclude() etc, all return a QuerySet.

What you're likely looking for is to first filter for the specific user, then get the latest result by 'id':

rule = Rule.objects.filter(user=user).latest('id')

See here for the docs on querying models