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Re:RE: IOT Vs Normal Tables

From: <>
Date: Tue, 26 Dec 2000 11:00:40 -0500
Message-Id: <>

Add one other item to that that is no longer true in 8.1.6. Oracle does not allow you to change the definition of the table, like adding columns.

____________________Reply Separator____________________
Subject: RE: IOT Vs Normal Tables
Author: Diana Duncan <> Date: 12/18/2000 1:20 PM

FYI, this statement is no longer true, at least not in 8.1.6.

"Currently, Oracle8 doesn't let you create

   additional indexes against an index-organized table."

I use IOT's quite a bit (because the app is very space conscious) but I'm thinking of getting rid of them if the export/import doesn't work. I guess I'll have to look into that...

-----Original Message-----
Sent: Friday, December 15, 2000 2:32 PM
To: Multiple recipients of list ORACLE-L

As usual, feeling like an idIOT for not knowing what "IOT" even means(!, actually, forgetting), I web searched, and found this stuff:

("Extensible Indexing - What is it and who needs it?":)
(author, Srikant Sarda )



   Identify the tables you can index-organize. Index-organized
   tables are easy to implement. They save space and reduce the
   number of I/Os necessary, because all table data is stored in
   the index structure. Currently, Oracle8 doesn't let you create
   additional indexes against an index-organized table. When
   identifying candidates, look for tables with only one index.
   Tables that have the most to gain from being index-organized
   are those where most of the data is already stored in the index
   (providing maximum space savings), where few changes
   occur to the table (this would cause index fragmentation), and
   cases in which the table is almost always accessed through
   the index. Reference tables often have these characteristics. 
Please see the official ORACLE-L FAQ:
Author: Diana Duncan

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Received on Tue Dec 26 2000 - 10:00:40 CST

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