in reply to OO Application Design

Ideally, it depends on how OO you want to be.
A good genalized version would be something like:

Entity (approximately a row in a database)
EntityHTML (HTML display class for Entities)

Person ISA Entity
PersonHTML ISA Person, ISA EntityHTML

In javaspeak, PersonHTML ISA Person, Implements EntityHTML.

Since your talking about RL, Person->new() should take a database ID, or an $Entity::NEWOB (a constant), or be created in Person::new_by_name('bob').

You'll want some way to flush the object back to the database, probably save(). But since (again in RL) you are talking about stuff in a database skip the save() and instead use add() and update() (or your synonyms). Trust me, it saves alot of confusion when reading code versus making save() 'smart'. Low-level things should be dumb, high level things should be smart. Don't forget delete()

A PersonHTML object just knows how to display a person - and nothing about the database - as an HTML form, or as a row on a list. Depending on your data you can throw in EntityPDF or EntityPNG as well. EntityPerl might be a neat one, but you probably just mean serialize().

There is lots of other stuff to think about, Factory classes and such, but tackle those when you need them :)

-jackdied