Caching/Pinning tables and indexes - Howto?

Question

Hi all,
I've hit upon a request by a COTS vendor to do something I'm not terribly familiar with....they want to 'cache' or 'pin' a table and an index in memory.
I was researching, and saw something to the effect of doing for Table1
ALTER TABLE Table1 CACHE;
However, the vendor was mentioning some examples that seemed to indicate creating a keep pool (a separate buffer cache pool?)...and then doing something like
ALTER TABLE Table1 STORAGE (buffer_pool KEEP)
Can someone give me some insight as to the difference between these two concepts...links on how to do it, etc?
Thanks in advance!
cayenne

Answer 1

burleson wrote:
Here is the script that I use to automate the assignment of tables into the KEEP pool.
BEWARE: This script is not for beginners:
http://www.rampant-books.com/t_oracle_keep_pool_assignment.htm
Hope this helps . . .
Dear Mr. Burleson,
I note that the article referenced makes the following comment about Oracle's suggestion for good candidates:
<ul>
+"It is easy to locate segments that are less than 10% of the size of their data buffer, but Oracle does not have a mechanism to track I/O at the segment level. To get around this issue, some DBAs place each segment into an isolated tablespace, so that the AWR can show the total I/O."+
</ul>
Oracle 9i introduced v$segstat - which tracks several different statistics at segment level. Statspack (when taking snapshots at level 7) and the AWR both capture and report segment level statistics. These statistics include the physical reads in 9i, and the number of segment scans in 10g.
Regards
Jonathan Lewis
http://jonathanlewis.wordpress.com
http://www.jlcomp.demon.co.uk