Hello, I'm new to Ruby/Rails and going through 'Beginning Rails 4'. In chapter 6 it has me create a join table for an articles and categories table (articles_categories). In the migrate file I've entered this code from the book: class CreateArticlesCategories < ActiveRecord::Migration def change create_table :articles_categories, :id=> false do |t| t.references :article t.references :category end end def self.down drop_table :articles_categories end end My issue is that after I migrate this file, when I try to make an association between the article and category object (article.categories << category) it spits an error that article_id does not exist in articles_categories table. It makes sense to me since the references above do no have _id appended in the class. If I change the class to the following, creating the relationship between article and category works fine: class CreateArticlesCategories < ActiveRecord::Migration def change create_table :articles_categories, :id=> false do |t| t.integer :article_id t.integer :category_id end end def self.down drop_table :articles_categories end end My question is, how can I get the 't.references' format to work so that AR looks for an 'articles' and 'categories' column, instead of the same with _id appended? Thanks -- 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+unsubscribe-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org To post to this group, send email to rubyonrails-talk-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org To view this discussion on the web visit https://groups.google.com/d/msgid/rubyonrails-talk/4f901d7c-bc93-44da-a338-3f889739e3f4%40googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.