Associations in models - am I doing it wrong?

rubyonrails-talk
1

One of my modesl looks like this:

class UnprocessedPage < ActiveRecord::Base

has_one :user

attr_accessible :url, :user_id

end

Do I need :user_id? Or is it implied via “has_one :user”?

This is working as is… but when I look for examples of other things, I never see any attributes with *_id… so I’m wondering if it’s implied and I’m just mucking things up?

2

You should not have a user_id column in the database for a has_one association. If UnprocessedPage has_one :user then User belongs_to :unprocessed_page and User should have an unprocessed_page_id column. Are you sure you do not mean User has_many :unprocessed_pages and UnprocessedPage belongs_to :user?

Have a look at the Rails Guide on ActiveRecord Associations for more details and if you have not already done so then work right through a good rails tutorial such as railstutorial.org, which is free to use online, in order to get the basics of Rails.

Colin

3

OK, yeah you are right. It shouldn’t be has_one. It sounds like the associated you mentioned is the one I’m looking for. With that said, would I still have a user_id column? or would that be implicit via the belongs_to?

4

OK, yeah you are right. It shouldn't be has_one. It sounds like the associated you mentioned is the one I'm looking for. With that said, would I still have a user_id column? or would that be implicit via the belongs_to?

Using belongs_to implies that you must provide a user_id column in the database. As I said, work through the tutorial and study the guides and all will become clear (well, less muddy at least).

Colin