Re: Object-relational impedence

From: Bob Badour <>
Date: Mon, 03 Mar 2008 14:54:00 -0400
Message-ID: <47cc494c$0$4037$>

topmind wrote:

> JOG wrote:

>>On Mar 3, 2:07 pm, Thomas Gagne <> wrote:
>>>All attempts by applications to access a DB's tables and columns
>>>directly violates design principles that guard against close-coupling.
>>>This is a basic design tenet for OO. Violating it when jumping from OO
>>>to RDB is, I think, the source of problem that are collectively and
>>>popularly referred to as the object-relational impedance mismatch.
>>I wondered if we might be able to come up with some agreement on what
>>object-relational impedence mismatch actually means. I always thought
>>the mismatch was centred on the issue that a single object != single
>>tuple, but it appears there may be more to it than that.
>>I was hoping perhaps people might be able to offer perspectives on the
>>issues that they have encountered. One thing I would like to avoid
>>(outside of almost flames of course), is the notion that database
>>technology is merely a persistence layer (do people still actually
>>think that?) - I wonder if the 'mismatch' stems from such a
> This came up in a nearby message. I borrowed the following text from
> wikipedia:

The text had too many blatant errors to start enumerating them all. The problem with wikipedia is any ignorant fool can just start typing nonsense. Even when one follows the requirements for references to primary sources, the quality of the end product can vary over many orders of magnitude. Received on Mon Mar 03 2008 - 19:54:00 CET

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