I think you’re looking for this: from django.db.models.loading import get_model model = get_model(‘app_name’, ‘model_name’) There are other methods, of course, but this is the way I’d handle it if you don’t know what models file you need to import into your namespace. (Note there’s really no way to safely get a model without first knowing …
Usually in instances where you need to provide a QuerySet, but there isn’t one to provide – such as calling a method or to give to a template. The advantage is if you know there is going to be no result (or don’t want a result) and you still need one, none() will not hit …
By default assertQuerysetEqual uses repr() on the first argument. This is why you were having issues with the strings in the queryset comparison. To work around this you can override the transform argument with a lambda function that doesn’t use repr(): self.assertQuerysetEqual(queryset_1, queryset_2, transform=lambda x: x)
Similar to Rails, we also have option to seed the database. It is done using management commands. In one of your apps, use the following folder structure <project>/<app>/management/commands/seed.py this makes python manage.py seed available as a management command. I personally follow the following structure. # <project>/<app>/management/commands/seed.py from django.core.management.base import BaseCommand import random # python manage.py …
blocked_delivery_times = BlockedDeliveryTime.objects.filter(delivery_date=delivery_date) \ .values(‘delivery_time’) delivery_times = DeliveryTime.objects.exclude(id__in=blocked_delivery_times)
You can do it in one of the following ways: from itertools import chain #compute the list dynamically here: my_obj_list = list(obj1, obj2, …) #and then none_qs = MyModel.objects.none() qs = list(chain(none_qs, my_obj_list)) You could also do: none_qs = MyModel.objects.none() qs = none_qs | sub_qs_1 | sub_qs_2 However, This would not work for sliced querysets
.filter(id__in=[1, 3, 4, 5, 6….]) Read more about it at Django docs.
Playlist.objects.filter(**{field_name: v})
I just had a similar issue. The problem was i had to return a QuerySet instance. A quick solution for me was to do something like this: active_serv_ids = [service.id for service in Service.objects.all() if service.is_active()] nserv = Service.objects.filter(id__in=active_serv_ids) I’m pretty sure this is not the prettiest and performant way to do this, but it …
Just call get, slice it, etc. and save as usual. The lock is in place through the transaction. ob = MyModel.objects.select_for_update().get(pk=1) Any changes are committed at the end of the transaction (which by default through 1.5 is per-request)