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    <p>This can be done quite easily using accepts_nested_attributes_for and fields_for:</p> <p>First in the User model you do the following:</p> <pre><code>class User &lt; ActiveRecord::Base has_many :subscriptions accepts_nested_attributes_for :subscriptions, :reject_if =&gt; proc { |attributes| attributes['queue_id'].to_i.zero? } # if you hit scaling issues, optimized the following two methods # at the moment this code is suffering from the N+1 problem def subscription_for(queue) subscriptions.find_or_initialize_by_queue_id queue.id end def subscribed_to?(queue) subscriptions.find_by_queue_id queue.id end end </code></pre> <p>That will allow you to create and update child records using the subscriptions_attributes setter. For more details on the possibilities see <a href="http://api.rubyonrails.org/classes/ActiveRecord/NestedAttributes/ClassMethods.html#M002132" rel="nofollow noreferrer">accepts_nested_attributes_for</a></p> <p>Now you need to set up the routes and controller to do the following:</p> <pre><code>map.resources :users do |user| user.resource :subscriptions # notice the singular resource end class SubscriptionsController &lt; ActionController::Base def edit @user = User.find params[:user_id] end def update @user = User.find params[:user_id] if @user.update_attributes(params[:user]) flash[:notice] = "updated subscriptions" redirect_to account_path else render :action =&gt; "edit" end end end </code></pre> <p>So far this is bog standard, the magic happens in the views and how you set up the params: app/views/subscriptions/edit.html.erb</p> <pre><code>&lt;% form_for @user, :url =&gt; user_subscription_path(@user), :method =&gt; :put do |f| %&gt; &lt;% for queue in @queues %&gt; &lt;% f.fields_for "subscriptions[]", @user.subscription_for(queue) do |sf| %&gt; &lt;div&gt; &lt;%= sf.check_box :queue_id, :value =&gt; queue.id, :checked =&gt; @user.subscribed_to?(queue) %&gt; &lt;%= queue.name %&gt; &lt;%= sf.text_field :random_other_data %&gt; &lt;/div&gt; &lt;% end %&gt; &lt;% end %&gt; &lt;% end %&gt; </code></pre>
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    1. COThanks! I have made the changes you suggested with some tweaks and have the basics working. One problem is that I am getting rows in subscriptions with 0 as the queue_id. This is when I untick the checkbox. Is it possible to have these rows deleted when not checked?
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    2. COtry the following line in the user model: accepts_nested_attributes_for :subscriptions, :reject_if => proc { |attributes| attributes['queue_id'].to_i.zero? }
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