[Python] Does `.all()` in Django re-query the Database or use the cache?

I am getting very conflicting messages. From Django Queryset docs, I am reading (https://docs.djangoproject.com/en/5.1/ref/models/querysets/#django.db.models.query.QuerySet.all):

When a QuerySet is evaluated, it typically caches its results. If the data in the database might have changed since a QuerySet was evaluated, you can get updated results for the same query by calling all() on a previously evaluated QuerySet.
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But then under the prefetch_related section, it shows that using .all() on the sub-objects uses results from the cache:

>>> restaurants = Restaurant.objects.prefetch_related(
... Prefetch("pizzas", queryset=queryset),
... )
>>> vegetarian_pizzas = restaurants[0].pizzas.all()


Here, apparently vegetarian_pizzas doesn't trigger a database query.

So...which is it - what does all() actually do? Why does it trigger a database query on the outer but then not for sub-objects? I'm confused.

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