Error when run migrations on Heroku, PostgreSQL with Rails 5

Question

I deploy Rails 5 with PostgreSQL to free app in Heroku. This is my configuration from database.yml:

production:
  adapter: postgresql
  username         


        

Answer 1

It seems like database is not provided for your app, you need to add one:

heroku addons:create heroku-postgresql

You can verify the database was added to your application by running:

heroku config --app your_app_name

Answer 2

After delete old DB, you should execute this

heroku pg:promote HEROKU_POSTGRESQL_NEW_DATABASE

You can check your DB nickname by

heroku pg:info

Answer 3

Follow some steps in serial order,

1. $ heroku login

2. In Gemfile, add the pg gem to your Rails project. Change:

   gem sqlite
   
   to

   gem 'sqlite3', group: :development
gem 'pg', '0.18.1', group: :production

3. In Gemfile, add the rails_12factor gem::

   gem 'rails_12factor', group: :production

4. $ bundle install

5. Ensure config/database.yml is using the postgresql adapter. Change:

   production:
<<: *default
database: db/production.sqlite3
   to
   

   production:
<<: *default
adapter: postgresql
database: db/production.sqlite3
   

6. $ git add .
$ git commit -m "Heroku config"
7. $ heroku create
8. $ git push heroku master
9. $ heroku run rake db:migrate
   I hope it worked.

SO FOLLOW STEP 5 correctly.