python - How to add an model instance to a django queryset?

Question

It seems like a django queryset behaves somehow like a python list.

But it doesn't support list's .append() method as I know.

What I want to do is like:

from my_django_app.models import MyModel

queryset = MyModel.objects.none()
queryset.append(MyModel.objects.first())      ## no list's .append() method!

Is there any way to add an model instance to an existing queryset?

Answer 1

You can also use the | operator to create a union:

queryset = MyModel.objects.none()
instance = MyModel.objects.first()
queryset |= MyModel.objects.filter(pk=instance.pk)

But be warned that this will generate different queries depending on the number of items you append this way, making caching of compiled queries inefficient.