Re: The wisdom of the object mentors (Was: Searching OO Associations with RDBMS Persistence Models)

From: J M Davitt <jdavitt_at_aeneas.net>
Date: Thu, 08 Jun 2006 13:34:41 GMT
Message-ID: <RHVhg.53053$mh.12669@tornado.ohiordc.rr.com>

Robert Martin wrote:
> On 2006-06-01 03:48:55 +0200, J M Davitt <jdavitt_at_aeneas.net> said:
>

>> Using file systems to make your point is a very poor choice.  Take a 
>> file, copy it over there.  Identical content, different paths.  Which
>> is "real?"  Which is a copy?   Which one should I modify if I want
>> my changes to persist?  How do Suzie and Bob and Joey and Ron know
>> which is the one I scribbled in?  What's keeping track of that?  A
>> file system?  No way!
>>
>> These, and other, questions become de minimis in the relational model.

>
>
> Are you suggesting that RDBs cannot have duplicate rows, or even
> duplicate tables?

Duplicate rows in the same table are absolutely prohibited.

Duplicate tables? Like two tables named CUSTOMER? Not in the same database.

If you think I was suggesting that the same value can't appear in more than one attribute, you missed the point.

> In any case, would you rather that your laptop prevented you from making
> copies of your files?

What's the point of making a copy? Increased entropy? Received on Thu Jun 08 2006 - 08:34:41 CDT