# ActiveRecord: removing validations or callbacks on a subclas **URL:** \ **Category:** Rails\ **Created:** [April 30, 2007, 10:45pm UTC](https://www.ruby-forum.com/t/activerecord-removing-validations-or-callbacks-on-a-subclas/103023 "2007-04-30T22:45:53Z")\ **Posts on this page:** 2\ **Page:** 1
**Author:** ![robertjames](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/r/e9c0ed/32.png) [@robertjames](https://www.ruby-forum.com/u/robertjames)\ **Post date:** [April 30, 2007, 10:45pm UTC](https://www.ruby-forum.com/t/activerecord-removing-validations-or-callbacks-on-a-subclas/103023/1 "2007-04-30T22:45:53Z")
Often a parent class has validations (or callbacks or associations) which I don’t want the subclass to have. Is there any simple way to remove these? ---
**Author:** ![robertjames](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/r/e9c0ed/32.png) [@robertjames](https://www.ruby-forum.com/u/robertjames)\ **Post date:** [April 30, 2007, 11:23pm UTC](https://www.ruby-forum.com/t/activerecord-removing-validations-or-callbacks-on-a-subclas/103023/2 "2007-04-30T23:23:56Z")
On 4/30/07, S. Robert J. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > Often a parent class has validations (or callbacks or associations) > which I don’t want the subclass to have. Is there any simple way to > remove these? Not really. Just don’t add them. If you have 5 sub classes, and only 3 of them need the validations or callbacks, set it up in a special mixin: module PickyCallbacks def self.included(base) base.after\_save :foo base.validates\_format\_of :email, :with =\> /…/ end end – Rick O. [http://lighthouseapp.com](http://lighthouseapp.com) [http://weblog.techno-weenie.net](http://weblog.techno-weenie.net) [http://mephistoblog.com](http://mephistoblog.com)