Caching data to reduce database hits

Are there any downsides to doing something like this assuming Foo data rarely changes?

class Foo < ActiveRecord::Base    class << self      def get_all_foo        @foo || Foo.find(:all)      end    end end

Is it ok to cache this data so you don't constantly reload it from the database? How long does @foo last? Just for the length of one request or until the server is restarted?

Thanks, Aaron

(sorry if this message is a dupe, I tried posting through the google interface first)

I believe that this will only last for the duration of a request. If you want it to be persistant, you could put it into the environment.rb file and it would persist over many calls.

Probably a better way to do this is to use memcache though. There are a number of good plugins that allow you to use this. A nice one by Chris Wanstrath can be found at

http://www.agilewebdevelopment.com/plugins/acts_as_cached

Hope that helps