Create a new Rails app with your choice of database and including the RSpec Testing Tool

Rails uses sqlite3 as the default database, but you can generate a new rails application with a database of your choice. Just add the -d option followed by the name of the database.

$ rails new MyApp -T -d postgresql

This is a (non-exhaustive) list of available database options:

• mysql
• oracle
• postgresql
• sqlite3
• frontbase
• ibm_db
• sqlserver
• jdbcmysql
• jdbcsqlite3
• jdbcpostgresql
• jdbc

The -T command indicate to skip the installation of minitest. To install an alternative test suite like RSpec, edit the Gemfile and add

group :development, :test do
  gem 'rspec-rails', 
end

Then launch the following command from the console:

rails generate rspec:install