Re: Reduce latch row cache objects with event 10089

From: MARK BRINSMEAD <mark.brinsmead_at_gmail.com>
Date: Wed, 18 Mar 2015 10:25:36 -0400
Message-ID: <CAAaXtLC46-Y=tf2rZ1JnuJ-B8TDrpdubuWdUAuDY6Dygew0fVw_at_mail.gmail.com>

Or an index may be used where there is another very-nearly-as-good option.

The fact that all the indexes are being used does not necessarily indicate that all indexes are actually needed. :-)

On Wed, Mar 18, 2015 at 7:32 AM, Jonathan Lewis <jonathan_at_jlcomp.demon.co.uk
> wrote:

>
> And some indexes may have been used when there was a better option.
>
> Regards
> Jonathan Lewis
> http://jonathanlewis.wordpress.com
> _at_jloracle
>
> ________________________________________
> From: Timur Akhmadeev [timur.akhmadeev_at_gmail.com]
> Sent: 18 March 2015 11:16
> To: Petr.Novak_at_trivadis.com
> Cc: Jonathan Lewis; oracle-l_at_freelists.org
> Subject: Re: Reduce latch row cache objects with event 10089
>
> On Wed, Mar 18, 2015 at 9:08 AM, Petr Novak <Petr.Novak_at_trivadis.com
> <mailto:Petr.Novak_at_trivadis.com>> wrote:
> I check continually index usage in shared pool and AWR, there are only
> 1-2 index candidates for elimination.
>
> Do not need to look into AWR for that. Start with listing indexes &
> indexed columns instead, just looking at what is indexed + at
> avg_data_blocks_per_key. Very often people introduce redundant &
> unnecessary/inefficient indexes which could be logically eliminated.
>
> --
> Regards
> Timur Akhmadeev
> --
> http://www.freelists.org/webpage/oracle-l
>
>
>

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Received on Wed Mar 18 2015 - 15:25:36 CET