Re: Clean Object Class Design -- What is it?

From: Adrian Veith <adrian_at_veith-system.de>
Date: Sat, 1 Sep 2001 14:18:15 +0200
Message-ID: <9mqjbh$dl9$02$1@news.t-online.com>

"Bob Badour" <bbadour_at_golden.net> schrieb im Newsbeitrag news:6QTj7.601$Ny1.123682876_at_radon.golden.net...

>

> I disagree that constraint declaration is programming. The ISO standard
> vocabulary requires a program to have both declarations and instructions
to
> satisfy some particular task. A constraint declaration is not a program
any
> more than a conceptual analysis is a program.

To make a distinction between a declaration and short method is quite needless.

> I understand that ODBMSes require one to program in order to enforce
> integrity because they generally treat integrity enforcement as nothing
more
> than a sub-task in every other task (or method, if you prefer).

I can see no reason, why a OODB should not have constraint declarations.

But the point is, if this is usefull ?
The advantage of checking constraints in a method is, that the checking can be done at the client side. Checking constraints at the server side is not that effective and in general limited.
If you define integrity, that a certain value is inside a given range, than the concept of constraint declarations is enough. But if things are getting more complex this concept fails. (SQL fails!).

Adrian Veith,
Veith System GmbH.
www.db-gonzales.de Received on Sat Sep 01 2001 - 07:18:15 CDT