How to add model instance to django request set?

Question

The django query seems to behave somewhat like a python list.

But it does not support the listapp () method, as I know.

I want to do the following:

from my_django_app.models import MyModel queryset = MyModel.objects.none() queryset.append(MyModel.objects.first()) ## no list .append() method! 

Is there a way to add a model instance to an existing set of queries?

Answer 1

No. A query set is a representation of a query — hence, a name is not an arbitrary set of instances.

If you really need the actual set of queries, not a list, you can try to collect the identifiers of the objects you need, and then get the objects through the __in request:

 list_of_ids = [] list_of_ids.append(my_id) ... queryset = MyModel.objects.filter(id__in=list_of_ids) 

It is not very effective.

Answer 2

You can also use the | To create a union:

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

But be careful, this will lead to the generation of various queries depending on the number of elements that you added in this way, making caching of compiled queries inefficient.

Answer 3

Queryset is not a list

So,

 to_list = queryset.values() 

Combine queryset

 from itertools import chain result_queryset = list(chain(queryset1, queryset2)) 

or

 querysets = [queryset1, queryset2] result_queryset = list(chain(*querysets))