Maximalist positions are a thing in our industry. Take a technique, outline its drawbacks, extrapolate you can’t use it under any circumstance, and ban it forever. We are lucky that Rails embraces exactly the opposite mindset as one of its pillars.| 37signals Dev
Active Record CallbacksThis guide teaches you how to hook into the life cycle of your Active Record objects.After reading this guide, you will know: When certain events occur during the life of an Active Record object. How to register, run, and skip callbacks that respond to these events. How to create relational, association, conditional, and transactional callbacks. How to create objects that encapsulate common behavior for your callbacks to be reused.| Ruby on Rails Guides
Active Record AssociationsThis guide covers the association features of Active Record.After reading this guide, you will know how to: Declare associations between Active Record models. Understand the various types of Active Record associations. Use the methods added to your models by creating associations.| Ruby on Rails Guides
Active Record BasicsThis guide is an introduction to Active Record.After reading this guide, you will know: How Active Record fits into the Model-View-Controller (MVC) paradigm. What Object Relational Mapping and Active Record patterns are and how they are used in Rails. How to use Active Record models to manipulate data stored in a relational database. Active Record schema naming conventions. The concepts of database migrations, validations, callbacks, and associations.| Ruby on Rails Guides
Active Record ValidationsThis guide teaches you how to validate the state of objects before they go into the database using Active Record's validations feature.After reading this guide, you will know: How to use the built-in Active Record validation helpers. How to create your own custom validation methods. How to work with the error messages generated by the validation process.| Ruby on Rails Guides
