django REST框架，如何与单个对象相关的预取

Question

由于某种原因，我将一个实例（不是查询集）传递给 ModelSerializer。但我想与这个实例进行 prefetch_lated 。

# instance is a Workout object
instance = queryset.order_by('?').first()
# I want to do something like: instance.prefetch_related('exercises') to avoid N+1 problem
workout = WorkoutModelSerializer(instance)
return Response(workout.data, status=status.HTTP_200_OK)

Answer 1

简单

instance = queryset.order_by('?').prefetch_related('exercises').first()

应该可以解决问题。