Step 1 – Installing PostgreSQL

  $ sudo apt update

  $ sudo apt install postgresql postgresql-contrib libpq-dev

Step 2 – Creating a New Database Role

  $ sudo -u postgres createuser -s <username> -P

  $ psql -U postgres --password

  postgres=# \password <username>

  postgres=# \q

Step 3 – Creating a New Rails Application

  $ cd ..

  $ rails new <app_name> -d=postgresql

  $ cd <appname>

Step 4 – Configuring and Creating Your Database

  $ echo 'export <app_name>_DATABASE_PASSWORD="<password>"' >> ~/.bashrc

  $ source ~/.bashrc

  $ nano config/database.yml

    // under default add the ff:

    username: <username>

    password: <%= ENV['<app_name>_DATABASE_PASSWORD'] %>

  $ rails db:create

    // if theres a problem in line 20, much better to 'Google the Error' algorithm