Add an activity feed to your application with Public Activity.

When displaying a count of records, this will generate extra SQL Queries. Learn how to reduce the number of SQL queries called with counter caching the number of associated records.

Part II - In this episode, we create performant links for adding, accepting/rejecting and removing friends for our social media application.

Active Record supports application-level encryption. The encryption layer sits between the database and the application. The application will access unencrypted data, but the database will store it encrypted. In this episode, we look at implementing encryption for a model's attribute and Action Text.

This is a Rails library which integrates with Active Records and provides some awesome user-initiated string interpolations for your web apps. For example, have you ever needed to allow users to insert their own variables into e-mail templates or messages?