Chapter 3. Active Record

Section 3.0.  Introduction

Recipe 3.1.  Setting Up a Relational Database to Use with Rails

Recipe 3.2.  Programmatically Defining Database Schema

Recipe 3.3.  Developing Your Database with Migrations

Recipe 3.4.  Modeling a Database with Active Record

Recipe 3.5.  Inspecting Model Relationships from the Rails Console

Recipe 3.6.  Accessing Your Data via Active Record

Recipe 3.7.  Retrieving Records with find

Recipe 3.8.  Iterating Over an Active Record Result Set

Recipe 3.9.  Retrieving Data Efficiently with Eager Loading

Recipe 3.10.  Updating an Active Record Object

Recipe 3.11.  Enforcing Data Integrity with Active Record Validations

Recipe 3.12.  Executing Custom Queries with find_by_sql

Recipe 3.13.  Protecting Against Race Conditions with Transactions

Recipe 3.14.  Adding Sort Capabilities to a Model with acts_as_list

Recipe 3.15.  Performing a Task Whenever a Model Object Is Created

Recipe 3.16.  Modeling a Threaded Forum with acts_as_nested_set

Recipe 3.17.  Creating a Directory of Nested Topics with acts_as_tree

Recipe 3.18.  Avoiding Race Conditions with Optimistic Locking

Recipe 3.19.  Handling Tables with Legacy Naming Conventions

Recipe 3.20.  Automating Record Timestamping

Recipe 3.21.  Factoring Out Common Relationships with Polymorphic Associations

Recipe 3.22.  Mixing Join Models and Polymorphism for Flexible Data Modeling