Message-ID: <413CBC77.7060806@nm.ru>
Date: Mon, 06 Sep 2004 12:37:27 -0700
From: "Daniel M." <xt@nm.ru>
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To: pgsql-sql@postgresql.org
Subject: Re: Storing properties in a logical way.
References: <413BDCB7.10009@nm.ru> <opsdu7wi2ecq72hf@musicbox>
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On Sun, 05 Sep 2004 19:51:44 +0200, Pierre-Frédéric Caillaud 
<lists@boutiquenumerique.com> wrote:

 >> But after looking closely at the list of a possible properties, i found
 >> out that some of them depend on others. For example, if item is a
 >> PDF document, it can have an index. But a document can also have an
 >> index with links. Logically, a properties like 'index with links'
 >> don't belong to the verification table - they look like a kind of
 >> a composite field - 'index with links' is not a stand-alone property,
 >> but it also implies that an item also has an 'index' property.
 >> On the other hand, it is impossible to decouple 'index' from
 >> 'with links', because the second part won't have any meaning without
 >> the first part.
 >
 >	You mean your properties would be better organized as a tree ?
 >	Or is it even more complicated than that ?

I never thought about that possibility - it is an interesting idea,
and it solves the logical problem (though there is still a need to
ensure that if child property is set, that the user won't be able
to also set a parent property - which is probably implementable by
using triggers).

Though I would prefer, if it is possible, something much simpler,
because there are only about 10 properties and 2 'composite'
properties - it would probably be an overkill to create a tree for
such a small table if a simpler solution exists.

Daniel.