reversable_data_migration

= Reversable Data Migration

Need to update a small amount of data in migration? But still want to make it reversable? Reversable Data Migration comes to the rescue.

== Example usage

class RemoveStateFromProduct < ActiveRecord::Migration
  def self.up
    backup_data = []
    Product.all.each do |product|
      backup_data << {:id => product.id, :state => product.state}
    end
    backup backup_data
    remove_column :products, :state
  end

  def self.down
    add_column :products, :state, :string
    restore Permission
  end
end