Django: prefetch_related grants performance only for non paginated requests?

Question

For example, I have 1000 Users with lots of related objects that I use in template.

Is it right that this:

User.objects.all()[:10]

Will always perform better than this:

User.objects.all().prefetch_related('educations', 'places')[:10]

Answer 1

This line will do an extra query to fetch the related objects for educations and places .

User.objects.all().prefetch_related('educations', 'places')[:10]

However it will only fetch the related objects for the sliced queryset User.objects.all()[:10] , so you don't have to worry that it will fetch the related objects the thousands of other users in your database.