OOP design: How to incorporate DB handling into application objects

Question

This is a design problem I face regularly and I\'d like to find some general insights about the subject. The code provided here is just an example.

In the design pha

Answer 1

It depends on your architecture. The four common Data Source Architectural Patterns can be found in Martin Fowler's Patterns of Enterprise Application Architecture:

• Table Data Gateway

  An object that acts as a Gateway to a database table. One instance handles all the rows in the table.

• Row Data Gateway

  An object that acts as a Gateway to a single record in a data source. There is one instance per row.

• Active Record

  An object that wraps a row in a database table or view, encapsulates the database access, and adds domain logic on that data.

• Data Mapper

  A layer of Mappers that moves data between objects and a database while keeping them independent of each other and the mapper itself.

Further patterns:

• http://martinfowler.com/eaaCatalog/index.html
• http://sourcemaking.com/design_patterns