How to do bulk update in rails on habtm association

Question

I have two models:

#user.rb

has_and_belongs_to_many :groups

#group.rb

has_and_belongs_to_many :users

I want to associate groups to users such that many users can be associated to many groups.

Front end side of the application is sending the user_ids and group_ids to the update method.

So in the UsersController, i've found out each user and associated that user with the groups.

def update
  users = User.where(id: [325, 326])
  users.each { |user| user.update(group_ids: [1, 2])}
end

I need to know the standard way of updating the associated records and what is the most efficient way of updating associated records?

Answer 1

There is a method update_all

def update
  users = User.where(id: [325, 326])
  users.update_all group_ids: [1, 2]
end