openproject/db/migrate/20120828171423_make_groups_users_a_model.rb

class MakeGroupsUsersAModel < ActiveRecord::Migration
  def self.up
    remove_index :groups_users, :name => :groups_users_ids
    rename_table :groups_users, :group_users
    add_index :group_users, [:group_id, :user_id], :name => :group_user_ids, :unique => true
  end

  def self.down
    remove_index :group_users, :name => :group_user_ids
    rename_table :group_users, :groups_users
    add_index :groups_users, [:group_id, :user_id], :name => :groups_users_ids, :unique => true
  end
end