Flatten migrations

A gem that adds rake db:flatten_migrations to rake tasks in your rails project.

You have to ensure that your schema format is set to :ruby in configuration of your project.
So in your project/config/environments/*.rb you should have a line:

config.active_record.schema_format = :ruby

Just add

gem 'flatten_migrations'

to development group in your Gemfile.

The task steps are as follows:

1. run pending migrations (rake db:migrate)
2. wipe out project/db/migrate direcotry
3. generate initial migration from existing database schema file initial migration is assumed to be the one which was last executed
4. create auxiliary migration which adjusts the schema_migrations table
5. run the new migration

Both new migrations (initial and auxiliary) are irreversible.

Your database is safe and it should not erase any data except the schema_migrations table.