scinote-web/db/migrate/20160125205500_add_empty_field_to_asset.rb

class AddEmptyFieldToAsset < ActiveRecord::Migration
  def up
    add_column :assets, :file_present, :boolean, default: false
    Asset.update_all(file_present: true)
    change_column_null :assets, :file_present, false
  end

  def down
    remove_column :assets, :file_present
  end
end