RE: Oracle Book Mal-practice...

From: William Wagman <wjwagman_at_ucdavis.edu>
Date: Fri, 22 May 2009 13:57:32 -0700
Message-ID: <2A8185DC02A8CE4C8413E0A26A8A831A03278875AA_at_XEDAMAIL2.ex.ad3.ucdavis.edu>



Greetings,

I remember Jonathan Lewis' test validating the claim that Oracle has anti-Microsoft code built in by showing it is possible to build an index named Microsoft that Oracle would not use. He was simply taking advantage of the way that oracle chooses to use indexes but it certainly was an entertaining and enlightening demonstration.

Bill Wagman
Univ. of California at Davis
IET Campus Data Center
wjwagman_at_ucdavis.edu
(530) 754-6208
From: oracle-l-bounce_at_freelists.org [mailto:oracle-l-bounce_at_freelists.org] On Behalf Of Robert Freeman Sent: Friday, May 22, 2009 10:48 AM
To: tomdaytwo_at_gmail.com; Oracle-L Freelists Subject: Re: Oracle Book Mal-practice...

To me... I think the truthful answer to a large majority of things is "It depends". We have experiences in our lives that we did X and X made things better... so all of a sudden X becomes the defacto way of doing things. We read X in a book is fact, and perhaps we are a bit too trusting. Perhaps X is a new technology and really nobody knows much of anything about X except what we learn by trial and occasional error. It's all an iterative process, fraught with error....

Be it separating tables and indexes, or whatever... I'm sure one could come up with case studies that would validate separating them, or storing them together.... It all depends.

I know I get a ton of heartburn out of the New Features titles in particular... new stuff, limited documentation or experience with it, short writing time frames..... I hate it when six months or a year later I start seeing presentations on this topic or that topic that add so much more detail that I wish I'd known at the time.

Then again, I love it when I give a new features presentation and share one new feature and half the room is scribbling like mad because THAT feature will better their lives.

Robert G. Freeman
Oracle ACE
Author:
OCP: Oracle Database 11g Administrator Certified Professional Study Guide (Sybex) Oracle Database 11g New Features (Oracle Press) Portable DBA: Oracle (Oracle Press)
Oracle Database 10g New Features (Oracle Press) Oracle9i RMAN Backup and Recovery (Oracle Press) Oracle9i New Features (Oracle Press)
Other various titles out of print now... Blog: http://robertgfreeman.blogspot.com The LDS Church is looking for DBA's. You do have to be a Church member in good standing. A lot of kind people write me, concerned I may be breaking the law by saying you have to be a Church member. It's legal I promise! :-) http://pages.sssnet.com/messndal/church/parachurch.pdf



From: Thomas Day <tomdaytwo_at_gmail.com> To: Oracle-L <oracle-l_at_freelists.org> Sent: Friday, May 22, 2009 9:03:58 AM
Subject: Re: Oracle Book Mal-practice... I was having a discussion with a junior DBA the other day about whether tables and indexes need to be in separate tablespaces and the issue of concurrent access came up.

My position is that Oracle always reads the index and the uses the rowid(s) to access the table. There is no issue of concurrent access. However, she pulled out the latest and greatest Oracle 11 book and sure enough the author repeated the old myth about concurrent access and the need to separate indexes and tables.

How can you fight this? With SANs and logical disks there's no certainty that separate tablespaces means that you're using separate read/write heads. I'm getting as tired of this argument as I am of the RAID5 argument. It shouldn't even be a point of discussion.

Doesn't Oracle have a vested interest in seeing that books about Oracle have correct information or does that just make for more opportunities for Oracle Consulting?

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Received on Fri May 22 2009 - 15:57:32 CDT

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