Delete all MySQL records while keeping the database schema

You will occasionally need to clean out your database while keeping the schema intact, e.g. when someone inserted data in a migration or when you had to kill -9 a frozen test process.

Old Capybara versions already have the Database Cleaner gem Show archive.org snapshot as dependency. Otherwise add database_cleaner to your *Gemfile`. This lets you say this from the Rails console:

DatabaseCleaner.strategy = :truncation
DatabaseCleaner.clean

You can package this into a nice little Rake task by copying the attachment into lib/tasks/clean_database.rake. Now you can e.g. clean the test database by saying on the shell:

rake db:clean RAILS_ENV=test

If you are using the parallel_tests gem, the task is aware and will clean all your test databases.