Re: Performance Tuning help

From: Sybrand Bakker <gooiditweg_at_nospam.demon.nl>
Date: Fri, 31 Jan 2003 20:17:37 +0100
Message-ID: <kpil3vgupdj1udt5qtvc6l71renj7f9e4t@4ax.com>

On Fri, 31 Jan 2003 16:19:11 -0000, "Gary Avery" <Gary.P.Avery_at_Pharmacia.com> wrote:

>missing. Is this what i should be doing or are there other 'quicker' gains
>to be made elsewhere. (I have already up'd the db_file_multiblock_read
>count)
>
>We run a multi-purpose application with all the datafiles stored on a single
>raid5 array (NT).
>
>Also has anyone done much with function based indexes? Would an index on
>UPPER(surname) gave a dramatic increase to selects...where surname like
>(upper(blah)). we tend to do a fair amount of those.

Quickest gains
- Get rid of the single RAID-5 array. It is very well known RAID-5 has a write penalty. Also your *single* RAID-5 array is a *single* point of failure. If the controller breaks down you are toast. - Maybe also get rid of NT
- Definitely get rid of your queries with upper(surname) = 'BLAH'
They always *by design* result in full table scans

Sybrand Bakker, Senior Oracle DBA

To reply remove -verwijderdit from my e-mail address Received on Fri Jan 31 2003 - 13:17:37 CST