# Creating objects with has\_many :through relationship **URL:** \ **Category:** Rails\ **Created:** [February 26, 2006, 5:37am UTC](https://www.ruby-forum.com/t/creating-objects-with-has-many-through-relationship/54189 "2006-02-26T05:37:53Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![adistarmid](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/f14d63/32.png) [@adistarmid](https://www.ruby-forum.com/u/adistarmid)\ **Post date:** [February 26, 2006, 5:37am UTC](https://www.ruby-forum.com/t/creating-objects-with-has-many-through-relationship/54189/1 "2006-02-26T05:37:53Z")
Three tables: users: id clients: id admin\_contacts: user\_id, client\_id class Client has\_many :admin\_contacts has\_many :contacts, :through =\> :admin\_contacts, :foreign\_key =\> :user\_id, :class\_name =\> ‘User’ end I added the :contacts for ease of use of grabbing the user objects associated with the admin\_contact. This all works great, I can grab the Users that are admin\_contacts for the client by doing: users = client.contacts =\> Array of User objects defined in the admin\_contacts table To add admin\_contacts to a client: client.admin\_contacts \<\< AdminContact.new( :user =\> user\_object ) I also thought this would work, but doesn’t: client.contacts \<\< user\_object Is this something that should work? Bob S. [http://www.railtie.net/](http://www.railtie.net/) ---
**Author:** ![adistarmid](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/f14d63/32.png) [@adistarmid](https://www.ruby-forum.com/u/adistarmid)\ **Post date:** [February 26, 2006, 5:44am UTC](https://www.ruby-forum.com/t/creating-objects-with-has-many-through-relationship/54189/2 "2006-02-26T05:44:12Z")
I had the same problem. The way I ‘solved’ it was: ac = AdminContact.new ac.user = user\_object client.admin\_contacts \<\< ac Why _that_ worked and the other does not, I do not know but would be willing to hear from someone more expert than me. Rob ---
**Author:** ![adistarmid](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/f14d63/32.png) [@adistarmid](https://www.ruby-forum.com/u/adistarmid)\ **Post date:** [February 26, 2006, 5:50am UTC](https://www.ruby-forum.com/t/creating-objects-with-has-many-through-relationship/54189/3 "2006-02-26T05:50:38Z")
Hi Rob, > ac = AdminContact.new > ac.user = user\_object > client.admin\_contacts \<\< ac and > client.admin\_contacts \<\< AdminContact.new( :user =\> user\_object ) are equivalent. I would think that :through associations have save capabilities. Anyone smarter than us know the answer? Surely Rick or Ezra know!?!? Bob S. [http://www.railtie.net/](http://www.railtie.net/) ---
**Author:** ![adistarmid](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/f14d63/32.png) [@adistarmid](https://www.ruby-forum.com/u/adistarmid)\ **Post date:** [February 26, 2006, 7:51am UTC](https://www.ruby-forum.com/t/creating-objects-with-has-many-through-relationship/54189/4 "2006-02-26T07:51:25Z")
> are equivalent. > I know, I _understand_ them as equivalent, I just did not > experience them as such, neither on my linux both nor > on windows. I came upon this by absolutely gutting the related classes and putting back together one line at a time including a re-gen of db and scaffolding. It was only when I made the above change did I get it to work. Here is stack from my original 2/23 post. Is this similar to what you are seeing? You have a nil object when you didn’t expect it! You might have expected an instance of Array. The error occured while evaluating nil.[] RAILS\_ROOT: ./script/…/config/… Application Trace | Framework Trace | Full Trace c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.13.2/lib/active\_record/base.rb:1509:in `read_attribute' c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.13.2/lib/active_record/base.rb:1198:in`id’ c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.13.2/lib/active\_record/base.rb:1209:in `quoted_id' c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.13.2/lib/active_record/associations/has_many_association.rb:169:in`construct\_sql’ c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.13.2/lib/active\_record/associations/has\_many\_association.rb:8:in `initialize' c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.13.2/lib/active_record/associations.rb:753:in`new’ c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.13.2/lib/active\_record/associations.rb:753:in `endorsees' c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.13.2/lib/active_record/associations.rb:749:in`endorsees’ #{RAILS\_ROOT}/app/controllers/claim\_admin\_controller.rb:50:in `create’ #{RAILS\_ROOT}/app/controllers/claim\_admin\_controller.rb:47:in `each' #{RAILS_ROOT}/app/controllers/claim_admin_controller.rb:47:in`create’ #{RAILS\_ROOT}/app/controllers/claim\_admin\_controller.rb:32:in `each’ #{RAILS\_ROOT}/app/controllers/claim\_admin\_controller.rb:32:in `create’ ---
**Author:** ![adistarmid](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/f14d63/32.png) [@adistarmid](https://www.ruby-forum.com/u/adistarmid)\ **Post date:** [February 26, 2006, 10:48pm UTC](https://www.ruby-forum.com/t/creating-objects-with-has-many-through-relationship/54189/5 "2006-02-26T22:48:16Z")
Bob- ``` I ran into a similar problem trying to save objects across ``` the :through relationship name like your :contacts. Its been a little while(2-3 weeks?) since I ran into the problem and dug into the source of :through. I ended up with the conclusion that it wasn’t in there to make that work correctly yet. It might have changed, I haven’t had a lot of time recently to troll over the patch list on trac. But last time I ran into this it was an equal pain as you are having now and so i ended up not using :through relationship names to save related objects through like that. ``` It seems like a natural thing to want to do though, I mean save ``` objects using the through set up. Not sure what the best workaround is right now. -Ezra