How do I update a table with rails using data from a form

I have a table in a database with two column开发者_运维问答s, Name and ID. I have a rails model for it named FakeTable.

I have a controller for the model:

class FakeTablesController < ApplicationController

    def index
        @data = FakeTable.find(:all)

    end

    def to_index
        redirect_to( :action => "index" )
    end

    def update

        redirect_to( :action => "index" )
    end
end

I have a form to display the information in this table:

<table>
  <thead>
    <tr>
      <th><%= "Name" %></th>
    </tr>
  </thead>
  <tbody>


  <% form_tag :action => "update" %>
  <% @data.each_with_index do |d, index| %>
   <% fields_for "d[#{index}]", d do |f| %>
   <tr>
     <td class="tn">Name: <%= f.text_field :name  %></td>
     <td class="tn">Id: <%= f.text_field :id  %></td>
   </tr>
   <% end %>
 <% end %>
  </tbody>
</table>
<%= submit_tag 'Update' %>
<%= end_form_tag %>

I have two questions. First, how do I use the ID to access each row in the table to display the data? Currently I use these two lines of code to access get each row in the table:

<% @data.each_with_index do |d, index| %>
   <% fields_for "d[#{index}]", d do |f| %>

I would like to change this so it uses the ID column instead.

My second question is, when I click the "Update" button, I want the data in the table to be updated from text fields in the form. How would I do that? I am using ruby on rails 2.3.8. Thanks!