migrating django-model field-name change without losing data

Changing the field name while keeping the DB field

Adding an answer for Django 1.8+ (with Django-native migrations, rather than South).

Make a migration that first adds a db_column property, and then renames the field. Django understands that the first is a no-op (because it changes the db_column to stay the same), and that the second is a no-op (because it makes no schema changes). I actually examined the log to see that there were no schema changes…

operations = [
    migrations.AlterField(
        model_name="mymodel",
        name="oldname",
        field=models.BooleanField(default=False, db_column=b'oldname'),
    ),
    migrations.RenameField(
        model_name="mymodel",
        old_name="oldname",
        new_name="newname",
    ),
]