Re: Principle of Orthogonal Design

From: DM Unseen <>
Date: Wed, 9 Jan 2008 04:49:57 -0800 (PST)
Message-ID: <>

On 9 jan, 02:51, JOG <> wrote:
> I was wondering what your current stances towards the principle of
> current design is cdt - info about the POOD is actually pretty sparse
> on google, which has not helped my own understanding. I gather that
> Date has realigned his opinion - although what to I know not - and
> that Darwen rejected the original POOD paper outright given that
> McGovern posits that:
> violates the principle, whatever the relations' attribute names.
> Instinctively it does seem rather odd that a predicates such as:
> * on Day:X the shop had noCustomers:Y
> * on Roll:A, the dice showed the Number:B
> cannot share the same database. Have I interpreted the debate
> correctly? Any insights or corrections are, as ever, appreciated -
> POOD is certainly thought provoking, and the concept that an update
> need not require specifcation of a table name is an interesting one.

My understanding is that the debate centers around typing.

Date advocates strong typing: ie X is of type "shop number" and A is a "roll number", both represent different aspects of the UOD so they have a different type (I disregard subtyping here for simplicity), *even if* the actual underlying representations (e.g. natural numbers) would be the same. Having different types, means the type engine can distinguish them.

DM Unseen Received on Wed Jan 09 2008 - 13:49:57 CET

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