Hack to Learn

create_table "states", :force => true do |t|
  t.string   "name"
  t.string   "abbreviation", :limit => 2
  t.datetime "created_at"
  t.datetime "updated_at"
end

# GET /cities/new
# GET /cities/new.xml
def new
  @city = City.new
  @states = State.find(:all, :order => :abbreviation)

  respond_to do |format|
    format.html # new.html.erb
    format.xml  { render :xml => @city }
  end
end

<% form_for(@city) do |f| %>
  <%= f.error_messages %>

  <p>
    <%= f.label :name %><br />
    <%= f.text_field :name %>
  </p>
  <p>
    <%= f.label :state_id %><br />
    <%= f.collection_select(:state_id, @states, "id", "abbreviation") %>
  </p>
  <p>
    <%= f.submit "Create" %>
  </p>
<% end %>