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From: Costin Cozianu <c_cozianu@hotmail.com>
Newsgroups: comp.databases.theory
Subject: Re: Database-valued attributes?
Date: Tue, 11 Nov 2003 12:01:36 -0800
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Xref: newssvr20.news.prodigy.com comp.databases.theory:22635

> Never a bad mode to be in. Perhaps you could ponder on this one. If a
> database contains relation *variables* does that mean that a Database Valued
> Atrribute also contains variables?
> 

There's hardly a sharp distinction to be made. Variables live in a 
context, and that context is a mapping from names to values. As such it 
can be regarded as a value. It's a very common trick in languages like 
Scheme and Lisp.

So while you can update a row to chage quantity from 1 to 2, you can 
update the same row, to change some other column to

{ ("varname" : newvalue) }

best,
Costin