class AddColumnToZipPacks < ActiveRecord::Migration[5.2]
  def change
    add_column :zip_packs, :container_id, :integer, default: 0
    add_column :zip_packs, :container_type, :string

    add_index :zip_packs, [:container_id, :container_type]

    ZipPack.all.update_all("container_type='HomeworkCommon', container_id = homework_id")
  end
end