Hi,
I’m still a new with ROR, but it’s really cool 
I just have this
problem with a project of mine.
I want to store email in a database. I already wrote a simple import
script, that works, so that’s not a problem. Showing the email
(efficiently) in a ROR site is.
These tables are in the database:
emails
id
email_id (foreign key -> emails.id)
seq
preamble
body
epilogue
headers
id
email_id (foreign key -> emails.id)
headerkeys_id (foreign key -> headerkeys.id)
seq
value
headerkeys
id
name
First, I thought I could use a HABTM (has and belongs to many), but
since the join table (headers) also contains extra information, like seq
and value, this shouldn’t be used, from what I read…
So, in ROR, I have these models defined:
email.rb:
class Email < ActiveRecord::Base
has_many :headers
has_many :headerkeys, :through => :headers
end
headerkey.rb:
class Headerkey < ActiveRecord::Base
has_many :emails
has_many :headers, :through => :headers
end
header.rb:
class Header < ActiveRecord::Base
belongs_to :email
belongs_to :headerkey
end
What I want to achieve, is to list all emails (a list like in every mail
client, with columns from, subject, date, etc), though a scaffold.
In the email_controller.rb, I have this:
def list
@email_pages, @emails = paginate :emails, :per_page => 10,
:conditions => [“email_id is NULL”]
end
And in the list view this (in short - only from colunn):
<% for email in @emails %>
This means that for 30 emails, in the case of 3 columns (from, subject,
date), a total of 32 SELECTS have to be done… That doesn’t look too
efficient
What would be the best way to do this ? Should I use a predefined JOIN
statement in the controller (with the paginate function) ? Or is it
possible to do this with the current controller and with some changes in
the view ?
Thanks in advance…
regards,
Leon