To: pgsql-sql@postgresql.org
Subject: Re: Storing properties in a logical way.
References: <413BDCB7.10009@nm.ru>
Message-ID: <opsdu7wi2ecq72hf@musicbox>
Date: Sun, 05 Sep 2004 19:51:44 +0200
From: =?iso-8859-15?Q?Pierre-Fr=E9d=E9ric_Caillaud?=
	<lists@boutiquenumerique.com>
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> 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 ?

	If it's a tree, look at the ways of storing a tree in a table.