If you need to display the record count for a has_many association, you can improve performance by caching that number in a column. (7 minutes)

One way to improve performance is to cut down on the number of SQL queries. You can do this through eager loading. Learn all about it in this episode! (4 minutes)

The final piece of the administration puzzle: authentication. There are many different approaches which is why I saved this step for last. This episode will cover a few techniques including the simple solution used for this site. (6 minutes)

In this second part of the series on administration, you will learn how to lock down the site to keep the public from accessing the administration features. (4 minutes)

This is the first part of a three part series on building an administration system. Many developers choose to separate it completely from the public side of the site by placing it into an admin subdirectory. This episode will show you an alternative and often better solution. (5 minutes)

Displaying flash messages in the layout can be a pain at times. In this episode you will learn an easy way to display any kind of flash message by looping through the hash. (1 minute)

It is often asked: how do I create a list of checkboxes for managing a HABTM association? Ask no more because this episode will show you how to do exactly that. (6 minutes)

Keep your controllers clean and forms flexible by adding virtual attributes to your model. This very powerful technique allows you to create form fields which may not directly relate to the database. (3 minutes)

You can pass more than simple strings to find conditions. Arrays, ranges, and nil values can be passed as well. In this episode you will see the tricks involved with passing these odd objects to find conditions. (Update: audio fixed). (4 minutes)

Did you know ActiveRecord provides class methods for performing calculations on models? You can even use these methods through associations. (2 minutes)