Django 2.0.7 deploy to Heroku

I create a Django 2.0.7 app to deploy to Heroku.

https://devcenter.heroku.com/articles/django-app-configuration

settings.py

import django_heroku
....
....
# Activate Django-Heroku
django_heroku.settings(locals())

And when I run it with debug mode in local web app, it's running well.

But it always shows error when I deploy it to Heroku.

"relation "auth_user" does not exist"

Heroku debug:
tail log command in Heroku:

heroku logs -t -a [heroku_app_name]

Then I found it always shows datatable does not exists.

2018-07-14T13:17:25.115046+00:00 app[web.1]: Internal Server Error: /api-token-auth/

2018-07-14T13:17:25.115060+00:00 app[web.1]: Traceback (most recent call last):

2018-07-14T13:17:25.115062+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/site-packages/django/db/backends/utils.py", line 85, in _execute

2018-07-14T13:17:25.115063+00:00 app[web.1]: return self.cursor.execute(sql, params)

2018-07-14T13:17:25.115065+00:00 app[web.1]: psycopg2.ProgrammingError: relation "auth_user" does not exist

2018-07-14T13:17:25.115067+00:00 app[web.1]: LINE 1: ...user"."is_active", "auth_user"."date_joined" FROM "auth_user...

2018-07-14T13:17:25.115068+00:00 app[web.1]: ^

Solution:

It seems database not been created.

So I run migrate command to Heroku:

heroku run python manage.py migrate -a [heroku_app_name]

And it works finally.

Root cause:
In local app build, the SQL connects to a existed Heroku data app.
But when I deploy it to Heroku web app, it will create another Heroku data app.
So Django migrations is prerequisite of deploying to Heroku.