How to determine if any field in a model / nested model changed?

Question

Is there some quick way to find out if any of a model\'s fields or any fields of it\'s nested models (a.k.a. associations) changed?

Answer 1

You can determine if an object has changed but not yet been saved by calling:

my_object.changed?

You can also determine if individual attributes have changed (say you have a first_name attribute):

my_object.first_name_changed?

As far as nested models go, I think you'd have to call changed? on them each individually.