I think this is an easy question, but i just don''t know the best way to do this. I have the following tables: - Exercises - Biking_details - Running_details. as you can see i have 2 kinds of Excercises: running and biking so i could do this: Exercise: has_one :biking_details has_one :running detail running_detail belongs_to :exercise biking_detail belongs_to :exercise. of course this could work, but these models would allow that an exercise would have both running and bking details, which is not possible when i would like to generate a list of exercisess with a column "exercise type", i would have to loop though a the list of exercises and for each record check if there is biking detail OR a running detail, generating a lot of queries i could solve this by adding a field exercise_type to the exercises table, but wouldn''t this be kind of redundant? so now i am having troubles to decide what to do who can give me some insight? 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 rubyonrails-talk-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org To unsubscribe from this group, send email to rubyonrails-talk+unsubscribe-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en -~----------~----~----~----~------~----~------~--~---