copy_team_users.rb

class CopyTeamUsers < ActiveRecord::Migration
  class User < ActiveRecord::Base
    has_and_belongs_to_many :teams
    has_many :team_user_tmps
    has_many :teams_tmp, :through => :team_user_tmps, :source => :team
  end
  class Team < ActiveRecord::Base
    has_and_belongs_to_many :users
    has_many :team_user_tmps
    has_many :users_tmp, :through => :team_user_tmps, :source => :user
  end
  class TeamUserTmp < ActiveRecord::Base
    belongs_to :team
    belongs_to :user
  end

  def up
    Team.find_each do |team|
      team.users_tmp = team.users
    end
  end

  def down
  end
end