update_attributes, updat & update_all, save

update column of table

update will change the state of object and database

update_attributes

ex:

rabbit.update_attributes( :name=> "peter",  :age=> 13)

update

ex:

Rabbit.update( 5, :name=>"peter", :age=>13)

update rabbit with id =5

update_all:

Rabbit.update_all(:name=>"peter")

all rabbits' names become "peter"

use save:

ex:

rabbit.name="peter"

rabbit.save

use save to update database