From: Martijn Tonies
Date: February 13 2009 9:40pm
Subject: Re: Codd's rule 8 (physical data idependence)
List-Archive: http://lists.mysql.com/mysql/216308
Message-Id: <02d401c98e23$aaa96ec0$1401a8c0@martijnws>
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Hi Jerry,

>>>*Applications should not be logicaly impaired when the physical storage
>>or
>>>access ethods change.*
>>
>>Changing the storage engine for tables, for example from a transactional
>>to non-transactional engine, changes the database logic.
>>
> [JS] Is that really an example of Codd's rule #8? It is a higher-level
> change than simply going from a hard drive to a RAM drive to magnetic 
> tape,
> any of which could conceivably be used with any of the storage engines.

I think you're right, but a "non transactional storage engine" fails on
a higher rule: namely the atomicy rule.

A non transactional engine is of near no use.

With regards,

Martijn Tonies
Upscene Productions
http://www.upscene.com

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