14->The Active Record Pattern（weiwei预定）

14
The Active
Record Pattern
The design patterns you’ve seen so far greatly improve the readability and maintainability of
script internals; however, none have confronted a fundamental requirement and challenge of
architecting and developing web applications: connecting to a database. This chapter and the
next two chapters―Table Data Gateway and Data Mapper―provide three design patterns that better
organize how your application interacts with a database.
The Problem
Most web applications persist information in a database. Is there a way to abstract database connectivity
to simplify table access and integrate persistence with business logic?
The Solution
Conceptually, the Active Record pattern is the simplest of the database-related design patterns. The
Active Record pattern embeds the knowledge of how to interact with the database directly into the