Rails - Mar 2006 - Strange behaviour of dates

Imagine a crud app that tracks people applying for a loan, here is the
layout I have:

Mysql database:
create table apps (
id int auto_increment primary key,
primary_id int not null,
secondary_id int null,
constraint fk_primary_id foreign key(primary_id) references (contacts.id),
constraint fk_secondary_id foreign key(secondary_id) references
(contacts.id))

create table contacts (
Id int auto_increment primary key,
Name char not null,
Date_of_birth date not null)


Models
app.rb
class App < ActiveRecord::Base
   belongs_to :primary,
    :class_name => "Contact",
    :foreign_key => "primary_id"
  belongs_to :secondary,
    :class_name => "Contact",
    :foreign_key => "secondary_id"
end

contact.rb
class Contact < ActiveRecord::Base
  has_many :apps_issued,
    :class_name => "App",
    :foreign_key => "primary_id"
  has_many :apps,
    :class_name => "App",
    :foreign_key => "secondary_id"
end

I have controllers to edit contacts individually and as a whole application.
When I look at the controller Contact from a browser and select a contact to
edit I get the proper form up on screen and this section:

      <label for="contact_date_of_birth"><b>Date of birth:
</b></label><br>

<%= date_select ''contact'',
''date_of_birth'', :start_year => 1900 %>

Returns 3 drop downs that are auto populated with the contacts dob in the
database.

Now when I go to the /App controller and get my list, I have a custom find
the basically looks like this:

  def edit
    @app = App.find(params[:id],
                    :joins => "LEFT OUTER JOIN contacts ON
apps.primary_id=contacts.id LEFT OUTER JOIN contacts AS secondary ON
apps.secondary_id=secondary_id",
                    :select => "apps.id, contacts.name as primary_name,
contacts.date_of_birth as primary_date_of_birth, secondary.name as
secondary_name, secondary.date_of_birth as secondary_date_of_birth")
  end

This line in my _edit.rhtml:

<label for="app_primary_date_of_birth"><b>Date of birth:
</b></label><br>

<%= date_select ''app'',
''primary_date_of_birth'', :start_year => 1900 %>

returns:

Showing app/views/app/_edit.rhtml where line #36 raised:

undefined method `year'' for "1993-02-05":String


/usr/local/lib/ruby/gems/1.8/gems/actionpack-1.11.2/lib/action_view/helpers/
date_helper.rb:222:in `select_year''
/usr/local/lib/ruby/gems/1.8/gems/actionpack-1.11.2/lib/action_view/helpers/
date_helper.rb:275:in `to_date_select_tag_without_error_wrapping''
/usr/local/lib/ruby/gems/1.8/gems/actionpack-1.11.2/lib/action_view/helpers/
date_helper.rb:274:in `to_date_select_tag_without_error_wrapping''
/usr/local/lib/ruby/gems/1.8/gems/actionpack-1.11.2/lib/action_view/helpers/
active_record_helper.rb:170:in `to_date_select_tag''
/usr/local/lib/ruby/gems/1.8/gems/actionpack-1.11.2/lib/action_view/helpers/
date_helper.rb:80:in `date_select''
#{RAILS_ROOT}/app/views/app/_edit.rhtml:36




So I guess the question of the century is what is done to the date of birth
when the Contact controller accesses it with the default find(:all) that is
not being done to it when I do my custom find that results in the error?

Any and all help will be greatly appreciated.

Daniel Salinas wrote:
> Now when I go to the /App controller and get my list, I have a custom find
> the basically looks like this:
> 
>   def edit
>     @app = App.find(params[:id],
>                     :joins => "LEFT OUTER JOIN contacts ON
> apps.primary_id=contacts.id LEFT OUTER JOIN contacts AS secondary ON
> apps.secondary_id=secondary_id",
>                     :select => "apps.id, contacts.name as
primary_name,
> contacts.date_of_birth as primary_date_of_birth, secondary.name as
> secondary_name, secondary.date_of_birth as secondary_date_of_birth")
>   end
> 
> This line in my _edit.rhtml:
> 
> <label for="app_primary_date_of_birth"><b>Date of
birth: </b></label><br>
> 
> <%= date_select ''app'',
''primary_date_of_birth'', :start_year => 1900 %>
> 
> returns:
> 
> Showing app/views/app/_edit.rhtml where line #36 raised:
> 
> undefined method `year'' for "1993-02-05":String
Extra-table attributes that are tacked onto a model instance using a
custom select, as well plain attr_accessor attributes, aren''t typed
column objects which can be used with multi-parameter AR helpers.

Instead use:

<%= select_date @app.primary_date_of_birth,
                 :prefix => ''app[primary_date_of_birth]'',
                 :start_year => 1900 %>

And in the app model:

def primary_date_of_birth
   Date.parse( self[primary_date_of_birth] )
end

def primary_date_of_birth= (d)
   self[:primary_date_of_birth] = Date.new(d[:year],d[:month],d[:day])
end


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