Re: Why is MySQL more chosen over PostgreSQL?

Sander Steffann <steffann@nederland.net>

From: "Sander Steffann" <steffann@nederland.net>
To: "Curt Sampson" <cjs@cynic.net>, "Christopher Kings-Lynne" <chriskl@familyhealth.com.au>
Cc: "Hannu Krosing" <hannu@tm.ee>, "Hackers" <pgsql-hackers@postgresql.org>
Date: 2002-07-31T08:35:12Z
Lists: pgsql-hackers
Hi

> And what's the problem with networkcard_products being a separate table
> that shares a key with the products table?
>
>     CREATE TABLE products (product_id int, ...)
>     CREATE TABLE networkcard_products_data (product_id int, ...)
>     CREATE VIEW networkcard_products AS
> SELECT products.product_id, ...
> FROM products
> JOINT networkcard_products_data USING (product_id)
>
> What functionality does table inheritance offer that this traditional
> relational method of doing things doesn't?

Well, if you also have soundcard_products, in your example you could have a
product which is both a networkcard AND a soundcard. No way to restrict that
a product can be only one 'subclass' at a time... If you can make that
restriction using the relational model, you can do the same as with
subclasses. But afaict that is very hard to do...

Sander.