Is there any method available to find changed attributes for objects?

I want to fetch only changed attributes of an object. Is there any method available which returns all the updated at开发者_如何学Pythontributes?

Given there aren't many specifics in your question, I'm going to assume you're referring to ActiveRecord objects. To view the changed attributes on so called "Dirty Objects" you can do the following:

User.changed #=> ["name", "email"]

User.changes #=> { "name" => ["Joe", "Joseph"] }

There are also methods for each attribute if you need to check specific ones.

User.name_changed? #=> true

User.name_change #=> ["Joe", "Joseph"]

More details here: http://ryandaigle.com/articles/2008/3/31/what-s-new-in-edge-rails-dirty-objects

Yes ActiveRecord:Dirty, however you can't see changes to objects saved to the Db, such as user.save :(