Gemfile

gem 'database_cleaner', group: :test

spec_helper.rb

RSpec.configure do |config|
  # ...
  config.use_transactional_fixtures = false
  
  config.before(:each) do
    DatabaseCleaner.strategy = if example.metadata[:js]
      :truncation
    else
      :transaction
    end
    DatabaseCleaner.start
  end
  
  config.after(:each) do
    DatabaseCleaner.clean
  end
end