[django] Django values_list vs values

In Django, what's the difference between the following two:

Article.objects.values_list('comment_id', flat=True).distinct()

vs

Article.objects.values('comment_id').distinct()

My goal is to get a list of unique comment ids under each Article. I've read the documentation (and in fact have used both approaches). The results overtly seem similar.

The best place to understand the difference is at the official documentation on values / values_list. It has many useful examples and explains it very clearly. The django docs are very user freindly.

Here's a short snippet to keep SO reviewers happy:

values

Returns a QuerySet that returns dictionaries, rather than model instances, when used as an iterable.

And read the section which follows it:

value_list

This is similar to values() except that instead of returning dictionaries, it returns tuples when iterated over.

values()

Returns a QuerySet that returns dictionaries, rather than model instances, when used as an iterable.

values_list()

Returns a QuerySet that returns list of tuples, rather than model instances, when used as an iterable.

distinct()

distinct are used to eliminate the duplicate elements.

Example:

>>> list(Article.objects.values_list('id', flat=True)) # flat=True will remove the tuples and return the list   
[1, 2, 3, 4, 5, 6]

>>> list(Article.objects.values('id'))
[{'id':1}, {'id':2}, {'id':3}, {'id':4}, {'id':5}, {'id':6}]

You can get the different values with:

set(Article.objects.values_list('comment_id', flat=True))