Django Migrations not updating Heroku PostgreSQL database

Question

I've been stuck on an issue for a while where I have a model that I've created locally (class User(AbstractUser)), ran "python manage.py makemigrations" and "python manage.py migrate", which works and interacts correctly with the django server when run locally.

When I push this to heroku however, I receive an error response to certain api requests which essentially say "relation "app_user" does not exist". I assumed this was because somehow the postgreSQL db didn't receive the migrations when the app was deployed to heroku. After logging into the db I noticed that it had a few other tables, including "auth_user" (I assume this is a default django table), but not "app_user". I have done "heroku run bash" and "python manage.py migrate" in an attempt to migrate the changes to the postgreSQL db, but this doesn't have any effect.

I'm not sure if this will be useful but the postgreSQL server I'm using is the standard Heroku Postgres Hobby Dev add-on.

My questions are:

• Should running "python manage.py migrate" on heroku update the postgreSQL database? If so, how does this work?
• Given that the migrations are all on heroku, how can I manually update the postgreSQL with the migrations?

Answer 1

Fixed by deleting old heroku db and creating a new one. Unsure what exactly caused the issue above but I feel it may be because we deleted all migrations on the repo at some point in the past (to start from scratch), which meant the current db state was not applicable to migrations in the repo and so could not be applied. After doing this, running migrate on the remote server works perfectly.