title: Rails: no implicit conversion of String into Integer
body: <pre><code>class CreateAdminUsersPagesJoin &lt; ActiveRecord::Migration[5.0]
    def up
      create_table :admin_users_pages2, :id =&gt; false  do |t|
        t.integer "admin_user_id"
        t.integer "page_id"
      end
      add_index :admin_users_pages2 ["admin_user_id", "page_id"]
    end
  
    def down
      drop_table :admin_users_pages2
    end
  end
  </code></pre>
  
  <p>When i run rake db:migrate
  It gets aborted and gives the following error:
   no implicit conversion of String into Integer</p>
  
  <p>Any help is appreciated.</p>