Oracle FAQ Your Portal to the Oracle Knowledge Grid
HOME | ASK QUESTION | ADD INFO | SEARCH | E-MAIL US
 

Home -> Community -> Usenet -> c.d.o.server -> Hash cluster formulas examples needed please

Hash cluster formulas examples needed please

From: <dataworks_at_zebra.net>
Date: Fri, 11 Sep 1998 21:43:43 GMT
Message-ID: <6tc5if$rjd$1@nnrp1.dejanews.com>


I have found using Hash clusters to be a great help in performance tuning... however, I am using a simple mod function.

 how do you allocate more than a single block?

here is my create cluster command:

create cluster transactions(customer_id integer) pctfree1 pctused 99 initrans 2 size 16k tablespace trans_main storage initial 200M next 200M pctincrease 0 freelists 4) hash is MOD(customer_id, 50000) hashkeys 50000;

I am using 16K blocks.
If I wanted to map - say 10 blocks per customer id instead of 1,

would I just say size 160K or would I change the hash function?

when I tried to map 10000 customers to 10000 keys I experienced terrible performance... so i used 50000 as my hash number and that worked, but I think that is still rather sloppy.

any help would be appreciated

Rob
Dataworks_at_zebra.net

-----== Posted via Deja News, The Leader in Internet Discussion ==----- http://www.dejanews.com/rg_mkgrp.xp Create Your Own Free Member Forum Received on Fri Sep 11 1998 - 16:43:43 CDT

Original text of this message

HOME | ASK QUESTION | ADD INFO | SEARCH | E-MAIL US