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From: Georg Bauhaus <sb463ba@l1-hrz.uni-duisburg.de>
Newsgroups: comp.lang.ada
Subject: Re: Windows Ada database support.
Date: Thu, 9 Dec 2004 18:58:45 +0000 (UTC)
Organization: GMUGHDU
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Date: 2004-12-09T18:58:45+00:00
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Dmitry A. Kazakov <mailbox@dmitry-kazakov.de> wrote:
 

: You have to modify all UPDATE
: statements if just a new column is added.

Nope.

: But data without semantics is a
: garbage.

Data with fixed semantics is inflexible :-)

: 
: I could derive new types from old bases and throw out
: old representations:

unless they carry some important information from the old design
still needed in other applications.

 
:> However, an object's type cannot reflect this, because types
:> are static.  You could associate one different type with each possible
:> combination of component values in your program...
: 
: 1. No application uses all possible combinations. They have very concrete
: things to do.

For example, they react to different value that an object has in time?