Forum: Ruby on Rails Self-referential many-many joins with :through

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Henry T. (Guest)
on 2006-03-30 01:18
(Received via mailing list)
I thought I had this nailed but.. now I'm seeing spots..

I've included my models below, feel free to ignore them. I'm really
just after an example that works. I couldnt find one on the wiki...
which is fair enough considering Ricks patch: that fixed them only went
through 5 days ago..


class Topic < ActiveRecord::Base

  has_many  :item_collection, :class_name => "Grouping",  :foreign_key
=> "item_id"
  has_many  :group_collection, :class_name => "Grouping",
:foreign_key => "group_id"

  has_many  :groups, :through => :group_colletion
  has_many  :items, :through => :item_collection


class Grouping < ActiveRecord::Base

  belongs_to  :item,
              :class_name => "Topic",
              :foreign_key => "item_id"

  belongs_to  :group,
              :class_name => "Topic",
              :foreign_key => "group_id"
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