puyopuyotetr.is/db/migrate/20170716191202_add_hide_notifications_to_mute.rb

require Rails.root.join('lib', 'mastodon', 'migration_helpers')

class AddHideNotificationsToMute < ActiveRecord::Migration[5.1]
  include Mastodon::MigrationHelpers

  disable_ddl_transaction!

  def up
    add_column_with_default :mutes, :hide_notifications, :boolean, default: true, allow_null: false
  end

  def down
    remove_column :mutes, :hide_notifications
  end
end