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From: Galen Boyer <galenboyer@hotpop.com>
Newsgroups: comp.databases.oracle.server
Subject: Re: Locally Managed Tablespaces ... again!!!
Date: 2 Feb 2003 16:15:06 -0600
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On 20 Jan 2003, joel-garry@home.com wrote:

>> That indexes and tables don't intrinsically (ie, generally)
>> contend. 

Okay, just so I can spew back what I think I understand after trying to
stay current with what has been said many different threads and many
different ways.  (Thanks Howard for never letting up.  As a reader, I
appreciate your soap box rantings.  They make me think more and be a
lemming less)

A table and its index have to be maintained on DML, but this maintenance
is done serially and therefore there is never any contention between
this maintenance.  A table and its indexes are two different objects
getting updated at different times, although, quite close in time when a
process updates a table's columns involved in an index.

So a question to try to summarize.

Q) Is there ever _any_ contention introduced between a table and its
   index when a single row is updated?

A) From the discussions, I'm confident the answer is NO.  Therefore, any
   contention between a table and its index is as arbitrary as
   contention between any other objects stored in the database.  The
   contention will arise because multiple processes are accessing the
   same object frequently, not because one process causes contention for
   itself.

In fact, one process can NEVER cause contention for itself?

-- 
Galen deForest Boyer
Sweet dreams and flying machines in pieces on the ground.
