[Answered ]-Django migration with 2 DBs?

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migrations.CreateModel does not create a model in the database upon instantiation. It is supposed to be present in the operations list where the migrations system will then use it to create the model. Furthermore you shouldn’t be writing this migration manually anyway! Just write the code for the model in models.py:

class MyModel(models.Model):
    # Your fields, etc.

Next since your question asks how to control which model is migrated to which database. These tasks are supposed to be done in the Database router, particularly in the allow_migrate method. You can check the values passed for db, app_label, and model_name return whether the model should be migrated there. For example:

class MyRouter:
    def db_for_read(self, model, **hints):
        ...

    def db_for_write(self, model, **hints):
        ...

    def allow_relation(self, obj1, obj2, **hints):
        ...

    def allow_migrate(self, db, app_label, model_name=None, **hints):
        # Suppose I want to migrate all models from the app 'some_app' to 'db1' only.
        if app_label in ['some_app']:
            return db == 'db1'
        # Suppose I want to migrate 'MyModel' to 'db2' only.
        if model_name == 'mymodel':  # 'mymodel' is lowercase 'MyModel'
            return db == 'db2'
        return None
👤Abdul Aziz Barkat

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