Adding a new role to PostgreSQL

rails@snarf:/var/www/mini-epic/current$ sudo -u postgres createuser --interactive
Enter name of role to add: rails
Shall the new role be a superuser? (y/n) y
rails@snarf:/var/www/mini-epic/current$ RAILS_ENV=staging rake db:create
rails@snarf:/var/www/mini-epic/current$ psql epic_invite_staging < /tmp/mini-epic.pgsql