Rails update_attributes without save?

Question

Is there an alternative to update_attributes that does not save the record?

So I could do something like:

@car = Car.new(:make => 'GMC') #other processing @car.update_attributes(:model => 'Sierra', :year => "2012", :looks => "Super Sexy, wanna make love to it") #other processing @car.save 

BTW, I know I can @car.model = 'Sierra', but I want to update them all on one line.

Answer 1

I believe what you are looking for is assign_attributes.

It's basically the same as update_attributes but it doesn't save the record:

class User < ActiveRecord::Base   attr_accessible :name   attr_accessible :name, :is_admin, :as => :admin end  user = User.new user.assign_attributes({ :name => 'Josh', :is_admin => true }) # Raises an ActiveModel::MassAssignmentSecurity::Error user.assign_attributes({ :name => 'Bob'}) user.name        # => "Bob" user.is_admin?   # => false user.new_record? # => true 

Answer 2

You can use assign_attributes or attributes= (they're the same)

Update methods cheat sheet (for Rails 6):

• update = assign_attributes + save
• attributes= = alias of assign_attributes
• update_attributes = deprecated, alias of update

Source:
https://github.com/rails/rails/blob/master/activerecord/lib/active_record/persistence.rb
https://github.com/rails/rails/blob/master/activerecord/lib/active_record/attribute_assignment.rb

Another cheat sheet:
http://www.davidverhasselt.com/set-attributes-in-activerecord/#cheat-sheet