Pro Active Record

Despite it's less than catchy name, ActiveRecord is a key part of the "magic" that makes Ruby on Rails such a hit. Without ActiveRecord, there would be no Rails. ActiveRecord is the connection between a Rails application and its data. Ruby and Ruby on Rails developers who want to exploit all the features of Ruby, of Rails, of their chosen database must learn ActiveRecord.
Pro ActiveRecord for Ruby picks up with ActiveRecord where most books on Ruby and the Rails framework leave off. Readers begin by learning about all the built-in assumptions that make it so wondrously easy to create freshly-built Rails applications from scratch. Next, readers learn how to adapt ActiveRecord to work with databases - and this includes just about all preexisting databases - that were designed without those assumptions in mind. Readers go on to learn how to tie ActiveRecord in with database-specific features such as stored procedures and large objects, how to migrate legacy database designs to work better with ActiveRecord, and how to extend ActiveRecord to provide new and innovative database functionality to their applications. Readers who absorb the knowledge given in this book will have a significant competitive advantage over those with only a superficial knowledge of the topic.