Re: Mixing OO and DB

From: David Cressey <cressey73_at_verizon.net>
Date: Wed, 13 Feb 2008 12:01:02 GMT
Message-ID: <2_Asj.2273$YL3.437_at_trndny05>


"Robert Martin" <unclebob_at_objectmentor.com> wrote in message news:2008021220540582327-unclebob_at_objectmentorcom...
> On 2008-02-11 15:28:39 -0600, "David Cressey" <cressey73_at_verizon.net>
said:
>
> > We do both deal with data,
> > don't we?
>
> Yes, but in very different ways, and with very different emphasis.
>
> OO is about structuring modules around behavior and hiding data. The
> structure and form of the data is hidden as deeply as possible, so that
> no other behaviors depend upon it.
>

If you can disregard Bob's rude tone without disregarding the content of his response, I ask you to do so.

Bob has pointed out that data independence is a stronger concept than data hiding.

I lean towards the idea that he is right, although I'm prepared to learn something new. (If it's really new, it will be surprising (see Shannon).

The one thing that, in my previous discussions with OO folks, I think the OO people have missed, it's the extent to which data independence renders encapuslation unnecessary.

> DBs are about structuring data, and the access to that data. Behaviors
> are secondary, and often hidden. One of the goals of a good data model
> is to facilitate as many behaviors as possible; and to depend on none
> of them.

Well put. Received on Wed Feb 13 2008 - 13:01:02 CET

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