ActiveRecord::Migration

@brunnogomes the official api doc?

Migrations can manage the evolution of a schema used by several physical databases. It’s a solution to the common problem of adding a field to make a new feature work in your local database, but being unsure of how to push that change to other developers and to the production server. With migrations, you can describe the transformations in self-contained classes that can be checked into version control systems and executed against another database that might be one, two, or five versions behind.

Full article: http://api.rubyonrails.org/classes/ActiveRecord/Migration...