python - Django - How to rename a model field using South?

Question

I would like to change a name of specific fields in a model:

class Foo(models.Model):
    name = models.CharField()
    rel  = models.ForeignKey(Bar)

should change to:

class Foo(models.Model):
    full_name     = models.CharField()
    odd_relation  = models.ForeignKey(Bar)

What's the easiest way to do this using South?

Answer 1

You can use the db.rename_column function.

class Migration:

    def forwards(self, orm):
        # Rename 'name' field to 'full_name'
        db.rename_column('app_foo', 'name', 'full_name')




    def backwards(self, orm):
        # Rename 'full_name' field to 'name'
        db.rename_column('app_foo', 'full_name', 'name')

The first argument of db.rename_column is the table name, so it's important to remember how Django creates table names:

Django automatically derives the name of the database table from the name of your model class and the app that contains it. A model's database table name is constructed by joining the model's "app label" -- the name you used in manage.py startapp -- to the model's class name, with an underscore between them.

In the case where you have a multi-worded, camel-cased model name, such as ProjectItem, the table name will be app_projectitem (i.e., an underscore will not be inserted between project and item even though they are camel-cased).