adrianh, your idea is very insightful and makes perfect sense from a pure Object Design view.

But I am thinking it would also make sense simply to keep the classes matching the tables, and view those classes as a middle layer between your perl code and the database tables.

The most straight forward view to look at this is, to take each table as an class, and the table's columns as properties of the class representing it. This is the basic route to move from traditional RD (relational database) towards modern OD (object database).

Assume the database design is alright, then there would be no need for a subclass of the price type class. If you need a subclass for price type class, so you can store extra info of a particular price type, then where does those extra info being stored in the database? There must be a need for extra columns and different table(s) (which disagrees with the assumption that the database is perfect.)

So if price type is a table to hold all price types, generally speaking, it indicates that there is no need for subclasses of the price type class.

Of course, those are just "generally speaking"... but would be usually alright.

Your thoughts?

In reply to Re: Re: Database design and Class::DBI by pg
in thread Database design and Class::DBI by Ovid

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