similar to: Has Many :through associations

Suppose I have a site about books and authors, and users can leave comments on either a book or an author. I''d want to have a table called "comments", which could belong to either an author OR a book. In my structure I wouldn''t be sure whether to include an "author_id" or a "book_id", or both. What would be the best way to handle this

Hello, Hope this isn''t a newbie question - but I don''t seem to be able to find relevent information elsewhere. I am having trouble getting the following to work: Schema ====== ActiveRecord::Schema.define(:version => 1) do create_table "authors", :force => true do |t| t.column "name", :string end create_table "books", :force =>

Good evening list members, I have the following model: class Author < ActiveRecord::Base has_many :authorships has_many :books, :through => : authorships end Should I be able to do the following? Author.find(:first).book_ids = [1,2,3] I ask, because it doesn''t. The docs state that it should, but it doesn''t specialise in the case of a :through This

I''ve got a User model and a Book model. A user is required to submit books each month to be reviewed by other users. I have the following relationships defined: # the join model book_review.rb belongs_to :user belongs_to :book end book.rb # each book is reviewed by many users. This allows us to get the BookReview # objects associated with this book has_many :book_reviews,

Hello, I''m learning A.R Associations by creating a simple forum that consists of 3 tables: ahuthors, topics and posts. This is the schema: class AddAuthorAndTopicAndPostTables < ActiveRecord::Migration def self.up create_table :authors do |t| t.column :username, :string t.column :email, :string t.column :created_on, :datetime end create_table

find_by_sql BREAKS THE OOP BEAUTY and perhaps we can solve that. NAMING CONVENTIONS can perhaps make find_by_sql much more clever. lets imagine that relation: publishers <- books <-> authors_books <-> authors -> universities (can''t find something else than university for that last association :) ) imagine we want to fetch every book and every associated

Hi, I am currently reading the Rails Recipes book and like the chapter on providing your own in_place_editor for enumerations / selects. I understood so far, or I believe that I understood ;-), how to do that for a field that uses values only, like choosing from "red", "black", "green". What I fail to understand is how to chose from associated objects?!

Hi. I have a problem with the association methods which passed to a model through a belongs_to declaration. Here''s an illustration of the issue: GIVEN: # migration class CreateArticlesAndAuthorsTables < ActiveRecord::Migration   def self.up     create_table :articles do |t|       t.text     :title       t.integer :author_id     end     create_table :authors do |t|       t.text

Hi, I have problem installing or running domU OS (Windows XP or Redhat 7.3). The machine runs CentOS 4.4 X86_64, Xen-3.0.3. Paravirtual domU works without problem. The problem is that when I run command "xm create <config>", nothing would happen. hvmloader does not seem get started at all. I''ve tried installing both 64bit and 32bit vnc, sdl but did not see any

Today I face with incorrect behavior in ActiveRecord. It take place when I try to use :include parameter for .find method. Where are two typical cases: 1. You have record with self-referential joins CREATE TABLE keywords (id, group_id); class Keyword < ActiveRecord::Base belongs_to :group, :class_name => "Keyword", :foreign_key =>

Hi all! I have just found something very strange. Let''s imagine that I have posts that belong to an author. If I do the following (the order doesn''t matter): apost.author = Author.find(3) apost.author_id = 2 I get a post that has both an :author_id => 2 attribute, and an associated Author with id 3. Then, post.save, and the author_id in the DB is 3. I think that this

Under Rails 2.3.2 using a completely brand new project, I have 2 models: class Author < ActiveRecord::Base # name:string end class Book < ActiveRecord::Base # title:string belongs_to :author # author_id end And a simple test where i create a Book with an Author using the belongs_to and then update the foreign key directly: require ''test_helper'' class BookTest

Hi, I am trying to create a Rest web service in my rails application. I need to configure urls for it as below. localhost:3000/book/book_id/new/param1/param2/param3/param4/... localhost:3000/book/book_id/next localhost:3000/book/book_id/delete I dont have a view pages for it since it returns in json format.Please help.So what is the best way to configure these urls via

Regarding validates_associated... Let''s say I have: article belongs_to author But for whatever reason, I want an article to also be written anonymously and therefore not require an author. Then I have: Article: belongs_to :author validates_associated :author But I DON''T have validates_presence_of. What I want to do is validate that an author is valid --if it is

I''ve been playing around with EdgeRails and checking out some of the new features. The one that will probably have the biggest affect on my designs is join models (or :through associations). For those not familiar with this feature, it lets you replace your habtm association with a pair of has_many associations indirected through an intermediate model class. Looks like good

(This message was originally written on StackOverflow -- the formatting is much prettier there -- http://stackoverflow.com/questions/1283046/problem-with-setter-override-on-activerecord) This is not exactly a question, it''s rather a report on how I solved an issue with write_attribute when the attribute is an object, on Rails'' Active Record. I hope this can be useful to others

Has anybody noticed validates_uniqueness_of missing in rails 3.0 rc2? I''m not sure if this is a bug or I''m just doing something wrong. Here''s what I''m doing. Class 1: class Title < ActiveRecord::Base validates_length_of :language, :is => 3 validates_uniqueness_of :language, :scope => :book_id validate :language,

Hi, Haven''t been able to find this raised before but I''m sure it must have been. When assigning an object to a belongs_to association I would like it to call the *association*_id= method instead of directly updating the attributes array. This is because I want to modify the behaviour when assigning a particular object without writing separate methods for whether it''s

Hi, I did not find any hints in the web where to configure/setup/manipulate the rx/tx ring buffer allocation within dom0 for xen-unstable, maybe someone here can nudge me towards the right knob. The problem: when booting a handful of domUs and connecting them (comprising a small experimental IP network with links and nodes etc.), some interfaces that have been given by the configuration files

Seemingly, when I use a symbol, I get an ActiveRecord error stating ''Can''t convert symbol into String.'' Why can''t I use a symbol here? Possibly this is a deeper misunderstanding of symbols in general on my part. #ActiveRecord error class Book < ActiveRecord::Base belongs_to :author, :class_name => :Person, :foreign_key => :author_id end #works