class BookGridWithPersistence < BookGrid

  override_column :author__name, :included => false

  def default_config
    super.merge :persistence => true
  end
end

class BookGridWithPersistence < BookGrid
  override_column :author__name, :included => false

  def configure
    super
    config.persistence = true
  end
end

Update config syntax in BookGridWithPersistence
Update config syntax in BookGridWithPersistence
