Re: Mixing OO and DB
Date: Mon, 10 Mar 2008 08:47:06 +0100
Message-ID: <47d4e742$0$14360$e4fe514c_at_news.xs4all.nl>
[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