self-joins are discussed here: http://guides.rubyonrails.org/association_basics.html#self-joins
self-referential association is discussed here: http://railscasts.com/episodes/163-self-referential-association The main difference I see is that self-referential association creates a join model, such as friendship, which links another model, such as user, to itself, so a user can have many friends (which are other users), and a friend can be befriended by a user. The self-joins looks like there is no join model. Simply a foreign key is added to the same model, such as a manager_id column to the employee model. An employee, who is a manager, can have many other employees, who are subordinates. And the link is done on the same table itself, association the employee manager_id column with the the employee id column. To me, these two techniques look virtually the same. Is there a difference and which is preferred? -- You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To unsubscribe from this group and stop receiving emails from it, send an email to rubyonrails-talk+unsubscr...@googlegroups.com. To post to this group, send email to rubyonrails-talk@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/rubyonrails-talk/bdd46a05-4cbe-4db3-ac90-679ffbdfedd5%40googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
