I hate to go overboard on this question but I think a lot can be learned here.
Your question dives into several sub-topics at once (database normalization, model associations, and ERD structures). I would concentrate on the following first: 1. Use a good diagramming ERD software (RISE is a good free one) This will help you create a visual diagram of your models and help you better define and establish relationships with them. 2. Database normalization. It's important to keep your database normalized but there are instances where you can go too far and create a very unwieldy structure. Read up on normalization and get a solid grasp on it before you get too deep in your project. 3. Model Associations Once you have done the above, I'd ask a few questions. First, let's talk about books in general and what is common about them. Books have titles (they can also have duplicate titles) Books have authors (single or multiple) Books have identification numbers Books have many editions Books can be hardback or paperback or electronic Books have value Books have conditions (age, wear, signed/unsigned, etc.) Second, as far as looking at a book as a simple object, what pieces should really go in the book model? While that's solely up to you I would drive the following: Book Model has_many :conditions title:string authors:text (you can serialize the field as JSON to store a hash) identification:string edition:string published_date:date hardback:boolean paperback:boolean It would be difficult to use ISBN as an ident on every book since it has only been uniquely assigned since 1970. Condition Model belongs_to :book book_id:integer age:integer signed:boolean torn:boolean pages_missing:boolean marked:boolean pristine:boolean Even though books have a published date, the edition might change the age of the book. I hope this example helps. -- 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 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/672babe344c5eb857f74450ffd7481fa%40ruby-forum.com. For more options, visit https://groups.google.com/d/optout.
