Re: A searchable datastructure for represeting attributes?

From: Ilya Zvyagin 2147483647 <ziv_at_fct.ru>
Date: Thu, 28 Feb 2002 12:58:46 +0300
Message-ID: <1014889951.479443_at_gatekeeper.fct.ru>

Hello, no_spam_for_me_at_thankyou.very_much! You wrote on Wed, 27 Feb 2002 14:13:00 -0500:

 nsf> I would love to. In fact we did use approach_2 for a a long time
 nsf> and unfortunately it proved impractical. Yes approach_2 has all the
 nsf> benifits I described plus as you correctly pointed out it's easier
 nsf> to report on. The problem is that in our case is 2-fold:

AFAIK and figure out things there is *no way* to combine these two approaches in general. You of course can put most intensively used attributes in a special table with ordinary relational structure like

objid, att1, att2, att3 etc.

but you lose flexibility anyway in this case.

I think you have chosen right approach in your situation. I don't believe queries against you structure can not be optimized and can not be fast. I think merge joins can help in this situation.

I know a developer in Russia who developed his system just in the way you described and his system already has been running in production successfully for years with much data in the database.

The structure in his system is slightly different. He put attributes with different types in different tables, each type in a separate table. I think this helps keeping values more selectable (raises selectivity) and automatically checks domain rules.

Hi did mention problems with query optimization but they was connected to some problems in MS SQLServer they use.

And one more interesting fact - they also use OLAP server in their system. A MS OLAP server and a different database for analytic queries. This is also an interesting technique.

I can give you a URL with materials on this but the site is in Russian unfortunately. But you still can look at table structures.

This is the URL, it is an article in ComputerPress magazine. http://www.compress.ru/Article.asp?id=2006

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Ilya Zvyagin, First Container Terminal of SPb Sea Port e-mail: masterziv_at_*KILLSPAM*mail.ru - personal, ziv@*KILLSPAM*fct.ru - business. ICQ UID: 29427861(MasterZIV) Received on Thu Feb 28 2002 - 10:58:46 CET