In one of my projects, we realized that we wanted to use Django Groups. We had some users in DB without any group. I wanted to create new groups and add existing users to one group.
I've decided to use migration for this.
First, I created an empty migration script.
python manage.py makemigrations users --empty
Next, I modified the created file to add proper migration.
from django.db import migrations def apply_migration(apps, schema_editor): db_alias = schema_editor.connection.alias Group = apps.get_model("auth", "Group") Group.objects.using(db_alias).bulk_create( [Group(name="group1"), Group(name="group2")] ) driver_group = Group.objects.using(db_alias).get(name="group1") User = apps.get_model("users", "User") users = User.objects.using(db_alias) driver_group.user_set.add(*users) def revert_migration(apps, schema_editor): Group = apps.get_model("auth", "Group") Group.objects.filter(name__in=["group1", "group2"]).delete() class Migration(migrations.Migration): dependencies = [("users", "0005_auto_20190724_0727")] operations = [migrations.RunPython(apply_migration, revert_migration)]