Ever working with a model and you forget what all of its columns are? Ever find yourself with your schema.rb open in a separate window so you can see what the structure is of your tables?

Dave Thomas, of Rails Pragmatic Studio fame (among a brazillion other things), hacked up a plugin that adds a comment block to the top of all of your model classes documenting the current schema for the given model. It ends up looking something like this:

</p>

	
Schema as of Sun Feb 26 21:58:32 CST 2006 (schema version 7)

  #
	
id                  :integer(11)   not null
	
quantity            :integer(11)
	
product_id          :integer(11)
	
unit_price          :float
	
order_id            :integer(11)   

  #

class LineItem < ActiveRecord::Base
belongs_to :product
</code></pre></notextile>
When the schema is updated, the comment is updated to reflect the new schema.
Install it with the plugin script:

script/plugin install http://svn.pragprog.com/Public/plugins/annotate_models

Run it with a custom rake task:



rake annotate_models


Check out the caveats in the README.
Thanks for sharing Dave.