An overkill solution would be:
bundle exec rake db:drop RAILS_ENV=test
bundle exec rake db:create RAILS_ENV=test
bundle exec rake db:schema:load RAILS_ENV=test
You could make this all in a rake task and run that.
Another solution from here is to include the following your spec_helper.rb file
config.after :all do
ActiveRecord::Base.subclasses.each(&:delete_all)
end
Disclaimer: I have not tested this and you should read the SO post as it may not work in all situations.
That being said, I would recommend using the database cleaner gem to avoid situations such as this.