damianham wrote: [...] > > If the 'folder.files' element was an array of ids then there would be > no subsequent database access to determine the size() value.
Not really true; it takes a query in either case. Your method still needs "SELECT file_ids FROM folders WHERE id = ?". That's not really going to perform any better than "SELECT count(*) FROM files WHERE folder_id = ?", especially not if files.folder_id is indexed. If you're really worried about performance, just cache Folder.file_ids so you don't have to query it every time. Or you could use a nested-set tree model (there are several Rails plugins that make this easy). But storing the child keys in the parent DB record is just asking for trouble. > > regards > damian Best, -- Marnen Laibow-Koser mar...@marnen.org http://www.marnen.org -- 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@googlegroups.com To unsubscribe from this group, send email to rubyonrails-talk+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en -~----------~----~----~----~------~----~------~--~---
