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Home -> Community -> Mailing Lists -> Oracle-L -> RE: Microsurvey - row count and global indexes in OLTP/DW
Interestingly enough (at least to me), assemble global index from local
indexes is one of a very few requests not yet implemented from the 1991-1993
Oracle VLDB group's list of over 60 requirements to make Oracle suitable for
large enterprise databases. Over 40% each went into 7.1 and 8.x, and a few,
such as classes of rollbacks by name for set transaction with exclusive and
willing to wait were apparently rejected for "ease of use", but I think
assemble global from locals may have died by omission rather than
intentionally.
When Oracle described how they planned to solve several of the functional requirements by implementing partitioning, one of the problems it was supposed to solve was time and space to build very large indexes.
Local indexes on each partition partially solved the problem, but being able to assemble a global index (match merge instead of an n log n minimum cost of sort) from the local indexes fell off the list at some point. Of course the dialog dwindled as the implementation phase began, and the players and roles had all changed by the time partitioning really started working well enough to notice.
I wonder if there is a significant enough market need for this feature to get it back under consideration. Of course in practice you would incur double index maintenance cost if you kept the locals from which you assembled the globals.
Tanel - In your experience, would quicker rebuild have been sufficient cause for you to keep the component locals? Any others with experience in very large globals care to chime in on this hypothesis?
mwf
-----Original Message-----
From: oracle-l-bounce_at_freelists.org [mailto:oracle-l-bounce_at_freelists.org]On
Behalf Of Tanel Põder
Sent: Tuesday, July 27, 2004 4:44 PM
To: oracle-l_at_freelists.org
Subject: Re: Microsurvey - row count and global indexes in OLTP/DW
Hi!
I had slightly less than billion in a DW if I recall correctly. Oracle 8.0.4.0.0 on Windows NT 4.0 :|
The global indexes on the tables were real pain, especially when one fell inconsistent with the table...
Tanel.
> Ross,
>
> Half a billion in a DW. Hope this helps.
>
> Tom Mercadante
> Oracle Certified Professional
-- Archives are at http://www.freelists.org/archives/oracle-l/ FAQ is at http://www.freelists.org/help/fom-serve/cache/1.html ----------------------------------------------------------------- ---------------------------------------------------------------- Please see the official ORACLE-L FAQ: http://www.orafaq.com ---------------------------------------------------------------- To unsubscribe send email to: oracle-l-request_at_freelists.org put 'unsubscribe' in the subject line. -- Archives are at http://www.freelists.org/archives/oracle-l/ FAQ is at http://www.freelists.org/help/fom-serve/cache/1.html -----------------------------------------------------------------Received on Tue Jul 27 2004 - 16:36:19 CDT
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