Migrate tables only to 1 database out of 2 in Django

Question

I am trying to create tables selectively in 1 database, but not the other.

In my example, I only want to create tables for the apps: tlocation and tcategory in the transforms database. However, Django is creating all tables in the transforms database.

Here is the DB router config:

TRANSFORM_APPS = ('tcategory', 'tlocation')


class TransformRouter(object):
    """
    A router to control all database operations on models in the
    "utils_transform" application.
    """
    def db_for_read(self, model, **hints):
        """
        Attempts to read 'transforms' models go to 'transforms' database.
        """
        if model._meta.app_label in TRANSFORM_APPS:
            return 'transforms'
        return None

    def db_for_write(self, model, **hints):
        """
        Attempts to write 'transforms' models go to 'transforms' database.
        """
        if model._meta.app_label in TRANSFORM_APPS:
            return 'transforms'
        return None

    def allow_relation(self, obj1, obj2, **hints):
        """
        Allow relations if a model in the 'tlocation' app is involved.
        """
        if obj1._meta.app_label in TRANSFORM_APPS or \
           obj2._meta.app_label in TRANSFORM_APPS:
           return True
        return None

    def allow_migrate(self, db, app_label, model=None, **hints):
        """
        Make sure the 'tlocation' app only appears in the 'transforms'
        database.
        """
        if app_label in TRANSFORM_APPS:
            return db == 'transforms'
        return None


class DefaultRouter(object):
    """
    Catch-all Router for all other DB transactions that aren't in the 
    ``utils_transform`` app.
    """

    def db_for_read(self, model, **hints):
        return 'default'

    def db_for_write(self, model, **hints):
        return 'default'

    def allow_relation(self, obj1, obj2, **hints):
        if obj1._state.db == obj2._state.db:
           return True
        return None

    def allow_migrate(self, db, app_label, model=None, **hints):
        return None

The command that I am using to run migrations is:

./manage.py migrate --database=transforms

When I migrate 1 app at a time only, as below, this works. But I can't run without an app filter in the migrate command. Example:

./manage.py migrate tlocation --database=transforms
./manage.py migrate tcategory --database=transforms

Answer 1

Have you tried managed = False for the models you don't want to create tables?

class MyModel(models.Model):
    ...
    class Meta:
        managed = False