Redmine/db/migrate/20090403001910_add_project_to_enumerations.rb

class AddProjectToEnumerations < ActiveRecord::Migration[4.2]
  def self.up
    add_column :enumerations, :project_id, :integer, :null => true, :default => nil
    add_index :enumerations, :project_id
  end

  def self.down
    remove_index :enumerations, :project_id
    remove_column :enumerations, :project_id
  end
end