Active Record

The official API documentation for Active Record as implemented in Rails.

A guide for getting SQLite installed on windows. Important as the default Rails DB is currently set to sqlite3.

A new entrant in Rails screencasts, Gregg and Jason bring their wit and creative production skills to an advanced Rails screencast. No doubt the most entertaining Rails screencast yet, and also full of great information. Priced at $9.

Rails database adapter that supports replicated MySQL databases.

If you want to access the ActiveRecord source code independently of Rails, you’ll find it here. (And yes, you can use ActiveRecord in non-Rails projects.)

Presentation from the Silicon Valley Ruby Conference 2007. A great overview of ActiveRecord

Nice cheatsheets for various aspects of Rails, including Active Record validation errors, migrations, form helpers, and Action Mailer.