‘NOT NULL constraint failed’ after adding to models.py
You must create a migration, where you will specify default value for a new field, since you don’t want it to be null. If null is not required, simply add null=True and create and run migration.
django-migrations
Django data migration when changing a field to ManyToMany
I realize this question is old and at the time the best option for Data Migrations was using South. Now Django has its own migrate command, and the process is slightly different. I’ve added these models to an app called books — adjust accordingly if that’s not your case. First, add the field to Book … Read more
How to reset migrations in Django 1.7
I would just do the following on both the environments (as long as the code is the same) Delete your migrations folder DELETE FROM django_migrations WHERE app = <your app name> . You could alternatively just truncate this table. python manage.py makemigrations python manage.py migrate –fake After this all your changes should get detected across … Read more
django 1.7 migrate gets error “table already exists”
If you have the table created in the database, you can run python manage.py migrate –fake <appname> Mark migrations as run without actually running them Or if you want to avoid some actions in your migration, you can edit the migration file under the app/migrations directory and comment the operations you don’t want to do … Read more
Django: OperationalError No Such Table
Use: python manage.py migrate –run-syncdb As stated in this comment by Benyamin Jafari: –run-syncdb – Creates tables for apps without migrations. Also don’t forget to specity app path. For example: python manage.py makemigrations app python manage.py migrate app
Django migration strategy for renaming a model and relationship fields
So when I tried this, it seems you can condense Step 3 – 7: class Migration(migrations.Migration): dependencies = [ (‘myapp’, ‘0001_initial’), ] operations = [ migrations.RenameModel(‘Foo’, ‘Bar’), migrations.RenameField(‘AnotherModel’, ‘foo’, ‘bar’), migrations.RenameField(‘YetAnotherModel’, ‘foo’, ‘bar’) ] You may get some errors if you don’t update the names where it’s imported e.g. admin.py and even older migration files … Read more
Django migrate –fake and –fake-initial explained
It is related to a database problem similar to a merge conflict in a source code (git) if you need to combine two branches with similar models or to switch between them. Nobody likes it intentionally. Imagine that you started to modify an application last week, maybe because you found a bug or you extended … Read more
How to revert the last migration?
You can revert by migrating to the previous migration. For example, if your last two migrations are: 0010_previous_migration 0011_migration_to_revert Then you would do: ./manage.py migrate my_app 0010_previous_migration You don’t actually need to use the full migration name, the number is enough, i.e. ./manage.py migrate my_app 0010 You can then delete migration 0011_migration_to_revert. If you’re using … Read more