# Model has\_many 3 degrees separation **URL:** \ **Category:** Rails\ **Created:** [March 5, 2009, 9:22am UTC](https://www.ruby-forum.com/t/model-has-many-3-degrees-separation/162048 "2009-03-05T09:22:13Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![Chad](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/ecccb3/32.png) [@Chad](https://www.ruby-forum.com/u/Chad)\ **Post date:** [March 5, 2009, 9:22am UTC](https://www.ruby-forum.com/t/model-has-many-3-degrees-separation/162048/1 "2009-03-05T09:22:13Z")
I feel like this should be simple but it’s stumping me. In the following model, is there an easy way to setup my models so that I can make the following call: @company.survey\_answers class Company \< ActiveRecord::Base has\_many :surveys has\_many :survey\_questions, :through =\> :surveys end class Surveys … belongs\_to :company has\_many :survey\_questions end class SurveyQuestions … belongs\_to :survey has\_many :survey\_answers end class SurveyAnswers … belongs\_to :survey\_question end Thanks in advance for any help. Cheers, Chad ---
**Author:** ![Chad](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/ecccb3/32.png) [@Chad](https://www.ruby-forum.com/u/Chad)\ **Post date:** [March 5, 2009, 10:14am UTC](https://www.ruby-forum.com/t/model-has-many-3-degrees-separation/162048/2 "2009-03-05T10:14:25Z")
On Thu, Mar 5, 2009 at 9:21 AM, Chad [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > Â has\_many :survey\_questions > end > > class SurveyQuestions … > Â belongs\_to :survey > Â has\_many :survey\_answers > end > > class SurveyAnswers … > Â belongs\_to :survey\_question > end What happens when you try: (1) @company.surveys.survey\_questions.survey\_answers or (2) @company.survey\_questions.survey\_answers I believe form (1) should certainly work after removing the line ‘has\_many :survey\_questions, :through =\> :surveys’ I am uncertain if form (2) will work (because I am uncertain if has\_many :through works that way and no time to test it here) I don’t see how ‘@company.survey\_answers’ could work since there is no has\_many relationship with the name ‘survey\_answers’ in the Company class. It is only defined in the SurveyQuestions class. HTH, Peter ---
**Author:** ![Chad](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/ecccb3/32.png) [@Chad](https://www.ruby-forum.com/u/Chad)\ **Post date:** [March 5, 2009, 10:31am UTC](https://www.ruby-forum.com/t/model-has-many-3-degrees-separation/162048/3 "2009-03-05T10:31:30Z")
I like the idea, but this is what I get: @answers = @company.surveys.survey\_questions.survey\_answers undefined method `survey\_questions’ for #Class:0x203b590 I feel like the first call, @company.surveys is just returning an array and then I’m trying to call the survey\_questions method on that array. Is there a way to modify that call to get the desired chaining? On Mar 5, 1:13 am, Peter V. ---
**Author:** ![Chad](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/ecccb3/32.png) [@Chad](https://www.ruby-forum.com/u/Chad)\ **Post date:** [March 5, 2009, 11:37am UTC](https://www.ruby-forum.com/t/model-has-many-3-degrees-separation/162048/4 "2009-03-05T11:37:21Z")
Ya I agree with you - I can manually combine arrays no problem, but then it’s a pain to sort and I’m unable to use named\_scope’s, etc. There’s got to be a clean way… ---
**Author:** ![Chad](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/ecccb3/32.png) [@Chad](https://www.ruby-forum.com/u/Chad)\ **Post date:** [March 5, 2009, 10:49am UTC](https://www.ruby-forum.com/t/model-has-many-3-degrees-separation/162048/5 "2009-03-05T10:49:44Z")
As you say @company.surveys returns an array of Surveys, so normally you would have to say @company.surveys[i].survey\_questions which will again return an array of questions, and so on. Are you asking for a means to automatically combine all the results obtained by iterating each of the arrays down the chain? I don’t know of a way to do that automatically, without iterating each of the arrays and building a combined list. I would not be in the least surprised to find that Ruby has some magic construct to achieve this however. Maybe this is a challenge to the Ruby geeks to provide the answer by the most concise (and possibly undecipherable) code. 2009/3/5 Chad [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) ---
**Author:** ![Chad](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/ecccb3/32.png) [@Chad](https://www.ruby-forum.com/u/Chad)\ **Post date:** [March 5, 2009, 12:02pm UTC](https://www.ruby-forum.com/t/model-has-many-3-degrees-separation/162048/6 "2009-03-05T12:02:39Z")
On Thu, Mar 5, 2009 at 10:13 AM, Peter V. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > (1) @company.surveys.survey\_questions.survey\_answers > > or > > (2) @company.survey\_questions.survey\_answers > > I believe form (1) should certainly work OK, that was stupid of me to post without testing first. Sorry for the noise it created. Peter ---
**Author:** ![Chad](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/ecccb3/32.png) [@Chad](https://www.ruby-forum.com/u/Chad)\ **Post date:** [March 5, 2009, 1:00pm UTC](https://www.ruby-forum.com/t/model-has-many-3-degrees-separation/162048/7 "2009-03-05T13:00:51Z")
If you wanted all the answers for a particular company then you could turn it round and find all the answers where survey\_question.survey.company = the\_company. But if you followed this route for all companies you would still have the problem of grouping the answers by company which is probably no better. 2009/3/5 Chad [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) ---
**Author:** ![Chad](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/ecccb3/32.png) [@Chad](https://www.ruby-forum.com/u/Chad)\ **Post date:** [March 5, 2009, 4:34pm UTC](https://www.ruby-forum.com/t/model-has-many-3-degrees-separation/162048/8 "2009-03-05T16:34:52Z")
Maybe the other way around… class Company has\_many :surveys def survey\_answers SurveyAnswer.all(:joins =\> {:survey\_question =\> {:survey =\> :company}}, :conditions =\> [‘companies.id = :company\_id’, {:company\_id =\> id}]) end end Greetings, Wojtek