hi, i''m a newbie digging ROR for a week (and loving it i might add) and trying to get a project done at the same time. i''m more used to direct SQL so trying to get hang of active record asssociations and figure out what is done for me and what is not by script/generate model and db:migrate. in a nutshell, i have 3 core models where users enter competitions with submissions. entities: - competition - user - submission will need to: pull all submissions by competition pull all users by competition pull all competitions by user pull all submissions by user 1. is this a case of has_many :through like so? class Competition < ActiveRecord::Base has_many :submissions has_many :users, :through => :submission end class Submission < ActiveRecord::Base belongs_to :competition belongs_to :submission end class User < ActiveRecord::Base has_many :submissions has_many :competitions, :through => :submissions end 2. do i create joining tables and define FKs by updating migration script manually? if there are materials on step instructions you can point me to, that will be great too! 3. if i need to add polymorphic behaviors(e.g. commentable and rateable) to each of these models, do i just pile up the association definitions? after adding on media and various type/category models, this probably will get pretty long and not sure whether cache/memory/ performance situation will become unmanageable. An example of relatively complex association definition will give me a good idea. thx for reading. -ji --~--~---------~--~----~------------~-------~--~----~ 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 -~----------~----~----~----~------~----~------~--~---