How can I overwrite a getter method in an ActiveRecord model?

Overriding the getter and using read_attribute does not work for associations, but you can use alias_method_chain instead.

def name_with_override
  name_trans || name_without_override
end

alias_method_chain :name, :override

Update: The preferred method according to the Rails Style Guide is to use self[:name] instead of read_attribute and write_attribute. I would encourage you to skip my answer and instead prefer this one.

---

You can do it exactly like that, except that you need to use read_attribute to actually fetch the value of the name attribute and avoid the recursive call to the name method:

def name 
  name_trans || read_attribute(:name)
end

The Rails Style Guide recommends using self[:attr] over read_attribute(:attr).

You can use it like this:

def name
  name_trans || self[:name]
end

I would like to add another option for overwriting getter method, which is simply ：super.

def name
  name_trans || super
end

this works not just on attributes getter method, but also associations getter methods， too。