diff --git a/db/migrate/021_add_articles_categories.rb b/db/migrate/021_add_articles_categories.rb
index a8c99ec..51d505b 100644
--- a/db/migrate/021_add_articles_categories.rb
+++ b/db/migrate/021_add_articles_categories.rb
@@ -1,6 +1,6 @@
 class AddArticlesCategories < ActiveRecord::Migration
   def self.up
-    create_table :articles_categories do |t|
+    create_table :articles_categories, :id => false do |t|
       t.column :article_id, :integer
       t.column :category_id, :integer
     end
--
libgit2 0.21.2