You could either use the find_by_sql method or the :joins method. (As someone has stated earlier that avoid find_by_sql for performance and maintanence reasons)
sample sql to put in find_by_sql in your model select question_id from responses r1 where not exists (select question_id from question q ) using :joins. (probably this would be better ) questions.find( :joins => "LEFT OUTER JOIN responses ON question_id = responses.question_id" :conditions => "responses.id is null") gurus, please comment on this. thanks, radha. badnaam wrote: > I have three models, Question, Response and User > > User has many question, :through Responses > > My response table has 3 main columns response, question_id and > user_id. > > The use case is lets say the user can respond to 100 question, but > during a session he responds to 20. How do I find out the ones he has > not respondeded to. In this case the response table will have 20 > records and I woukd like to show the user the rest of the 80 he has > not responded to. > > Thanks -- Posted via http://www.ruby-forum.com/. -- You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en.
