title: Rails generate model refrences but not belongs_to
body: <p>So I have a Ruby-on-Rails application that should have the following models: <code>Order</code>, <code>OrderItem</code>, and <code>Product</code></p>
  
  <p>I wanted to generate the <code>OrderItem</code> model, for this I used: </p>
  
  <pre><code>rails g model OrderItem order:references product:references quantity:integer selling_price:decimal
  </code></pre>
  
  <p>The result model is:</p>
  
  <pre><code>class OrderItem &lt; ApplicationRecord
    belongs_to :order
    belongs_to :product
  end
  </code></pre>
  
  <p>Technically, the <code>OrderItem</code> correctly belongs_to <code>Order</code> this is correct. Technically however it does not "belong to" but at most <code>has_one :product</code>. Changing this by correcting the generated model is of course easy. Been wondering if there's a correct Ruby way for generating a has_one relation though. Was using references in this case wrong, and there's a correct way to do this?</p>