Touching ActiveRecord models is quite a common thing in most of the Rails applications, especially useful for cache invalidation. By default, it updates updated_at timestamp with the current time, Here’s a typical example of using touch in a model:

class Photo < ApplicationRecord
  belongs_to :user, touch: true
end

Whenever a new photo is created, or the existing one is updated/destroyed, the updated_at attribute of the associated user will be updated with the current time. In the majority of the cases, this is the desired behavior (it’s one of those rare ActiveRecord callbacks that is not that bad ;)). However, it might happen that you may not want touch to be executed for some reason. Is there any built-in solution that could solve that problem?

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