Re: Mixing OO and DB

From: mAsterdam <>
Date: Mon, 10 Mar 2008 08:47:06 +0100
Message-ID: <47d4e742$0$14360$>

[snip denormalization vs materialized views]

Brian Selzer wrote:
> Patrick May wrote:

>> Brian Selzer writes:
>>> Patrick May wrote: 
>> ... decoupling the application logic from the database schema.

> I don't agree with this. You're equating the database schema with the
> database implementation. The schema specifies what information is to be and
> can be recorded. As such the schema is an integral part of the application
> specification, and it cannot be decoupled, but that doesn't mean that the
> database implementation cannot. The schema does not specify how information
> is physically recorded, nor does it specify the process by which the
> recording takes place.

The failure to make this distinction (what vs how with regard to data) would score high on a hypothetical top ten of 'misconceptions to get rid of a.s.a.p. - for DB beginners with an OO background'.

The DB / DBMS blur stems from a similiar blind spot. It is telling that, where Patrick attributed his DB / DBMS mix-up to sloppy wording, Dmitry stated that this non-distinction is necessary (to keep his formal system consistent - mA).

> That belongs to the implementation, and that can
> certainly be decoupled and probably should be.

Trying to make and maintain this decoupling is, IMO, a cornerstone for sound database thinking and software development.

What you see depends on where you stand.
Received on Mon Mar 10 2008 - 08:47:06 CET

Original text of this message