Re: IOT Vs Normal Tables

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?":) http://technet.oracle.com/products/oracle8i/htdocs/ext.htm (author, Srikant Sarda mailto:srsarda_at_us.oracle.com )

-
http://technet.oracle.com/products/oracle8i/htdocs/ext.htm

---
excerpt:

   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. 
...

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On 15 Dec 2000, at 7:31, Murali Vallath wrote:

Date sent:      	Fri, 15 Dec 2000 07:31:10 -0800
To:             	Multiple recipients of list ORACLE-L <ORACLE-L_at_fatcity.com>
From:           	"Murali Vallath" <murali_vallath_at_hotmail.com>
Subject:        	Re: IOT Vs Normal Tables



> Since the index and data are stored together, my impression on this subject 

> was IOT's will save you the extra I/O for the data lookup.

> 

> With the B-TREE index structure being common, the savings should be in the 

> data lookup.

> 

> Also, from the Oracle Internals class I had the opportunity to attend in 

> October, at Hustone TX, the instructor told us that with 9i the data 

> dictionary will be using IOT.

> 

> I have not tested it myself, but these are from training, conversations and