Note in-line:
--
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
"Jonathan Lewis" <jonathan_at_jlcomp.demon.co.uk> wrote in message
news:c4bbir$icb$1_at_hercules.btinternet.com...
>
> But everyone who reads the paper can also note the following
> preamble to the test:
> <<quote>>
>
> For example, large (16-32K) blocksize data
> caches can be used to contain data from indexes or
> tables that are the object of repeated large scans or
> tables that would always suffer from row migration
> or chaining.
>
> <<end quote>>
>
The point I was making, but forgot to state
explicitly, was that the author STATES that
there are special cases worthy of consideration,
and then gives an example of a special case.
My follow-up was only trying to put a finger on
how special the case was.
> The test case is not fully described, but let's we assume
> the cleanest example that would fit the details - the table
> has an id which is sequence based, the query is an
> "index-only" query which does a range scan rather than
> a fast full scan, and the index was built clean with the
> default of pctfree 10, then the query has to be something like:
>
> select /*+ index(t1) */
> count(*)
> from t1
> where id between 1 and 380000
>
Received on Tue Mar 30 2004 - 02:56:28 CST
