Question

I have a Customers model:

class Customer < ActiveRecord::Base
  has_many    :phone_numbers
end

and a Phone Numbers model

class PhoneNumber < ActiveRecord::Base
  belongs_to :customer
end

In my view, I’m doing this:

<table id="customerSearch">
  <tr>
    <th>Last name</th>
    <th>First name</th>
    <th></th>
    <th></th>
    <th></th>
  </tr>
<% @customers.each do |customer| %>
  <tr>
    <td><%= customer.last_name %></td>
    <td><%= customer.first_name %></td>
    <td><%= link_to 'Show', customer %></td>
    <td><%= link_to 'Edit', edit_customer_path(customer) %></td>
  </tr>
<% end %>
</table>

and here is my controller for this action:

def index
  @customers = Customer.find(:all, :limit => 10, :order => 'last_name')
  flash.now[:notice] = 'Enter customer last or first name. Fields are case-sensitive.'
end

In the table in my view, I want to show the first phone number found for each customer listed in a phone number column – like:

Last Name    first Name    Phone

Smith        John          3258889322
Jones        Davey         3412555232

I’ve come up with multiple solutions to this problem, but none was very elegant. There must be a ‘Rails Way’ to do this that is really snazzy, as this seems like a common situation for a web application developer to be faced with.

Answer 1

In your view:

<table id="customerSearch">
  <tr>
    <th>Last name</th>
    <th>First name</th>
    <th>Phone</th>
    <th></th>
    <th></th>
  </tr>
<% @customers.each do |customer| %>
  <tr>
    <td><%= customer.last_name %></td>
    <td><%= customer.first_name %></td>
    <td><%= customer.phone_numbers.first.number if customer.phones.exists? %>
    <td><%= link_to 'Show', customer %></td>
    <td><%= link_to 'Edit', edit_customer_path(customer) %></td>
  </tr>
<% end %>
</table>

Your association will take care of creating those phone-number-related attribute accessors for you. You can see all of the methods that are created for you with a has_many association here.