Understanding ActiveRecord: A Gentle Introduction to the Heart of Rails (Part 2)
Subject:   Very good article, but a couple of errors
Date:   2007-05-11 23:30:45
From:   tfardella
This article did a great job of introducing ActiveRecord. The only problem I found were mistakes in the code presented that made it difficult to get everything working correctly. The 005_create_taggings.rb file should read:

class CreateTaggings < ActiveRecord::Migration
def self.up
create_table :taggings do |t|
t.column :entry_id, :integer
t.column :tag_id, :integer

def self.down
drop_table :taggings

The tags/index.rhtml file shown was mistakenly copied from the entries/index.rhtml file. It should read:

<h2>URLs for All Tags</h4>

<% @urls_for_tags.each do |tag,url_list|%>

    <% url_list.each do |url| %>
  • <%= url %>

  • <% end %>

<% end %>

If you download the source files linked to at the end of the article they contain the correct code.

Thanks for the great article. I hope to see more like it in the future, hopefully with better proof-reading.