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Home -> Community -> Mailing Lists -> Oracle-L -> RE: Why "Separating Data and Indexes improves performance" is a myth?
true!
-----Original Message-----
From: oracle-l-bounce_at_freelists.org
[mailto:oracle-l-bounce_at_freelists.org]On Behalf Of Jonathan Lewis
Sent: Friday, April 23, 2004 2:53 PM
To: oracle-l_at_freelists.org
Subject: Re: Why "Separating Data and Indexes improves performance" is a
myth?
Alas, even that isn't necessarily true.
What if you have a low update rate, but a high read rate. You've just isolated a disc, or two, for a very low level of redo I/O, and reduced the number of devices which are subject to the heavy I/O load.
Sometimes the penalty on redo is less important than the benefit on reads.
Regards
Jonathan Lewis
http://www.jlcomp.demon.co.uk
The Co-operative Oracle Users' FAQ
http://www.jlcomp.demon.co.uk/faq/ind_faq.html
April 2004 Iceland http://www.index.is/oracleday.php June 2004 UK - Optimising Oracle Seminar July 2004 USA West Coast, Optimising Oracle Seminar August 2004 Charlotte NC, Optimising Oracle Seminar September 2004 USA East Coast, Optimising Oracle Seminar September2004 UK - Optimising Oracle Seminar
So in laying out disks for a new database - perhaps the only thing worth =
=3D
separate out is the redo based on I/O contention - right? =3D20
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