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Re: Index maintenance...

From: Richard Foote <richard.foote_at_tbigpond.nospam.com>
Date: Wed, 05 May 2004 13:56:47 GMT
Message-ID: <zo6mc.21720$TT.506@news-server.bigpond.net.au>


"Volker Hetzer" <volker.hetzer_at_ieee.org> wrote in message news:c7abns$lm2$1_at_nntp.fujitsu-siemens.com...
> Hi!
> We've got a consultant (for a canned app) here who just hinted at a
possible performance improvement
> if one recreates the indexes after a big load.
> He said he noticed an improvement but didn't run any benchmarks. He used
8.1.something and 9.0.something.
> We are using 9.2.0.4.
> So, what's behind this?
> Does this apply to us too?
>
> Lots of Greetings!

Hi Volker,

When I hear someone say something like that, two questions immediately spring to mind.

The first is simply why ? Ask the consultant why should a big load result in an index now being detrimental to performance. Here's a whiteboard, please explain. If they can't or if they provide an explanation that is unclear, illogical, wrong (from your knowledge which can always be a tad dangerous), suspicious, etc. then respond accordingly and best treat with suspicion. If however their explanation is clear, plausible, reasonable, etc. then move onto the second question.

The second question being, can you benchmark and prove your explanation. Show me evidence to support your claim, preferably in my environment. If they can't, then again remain highly sceptical. If however they can produce evidence that re-enforces their claim, then yes, agreed, they could have a point.

Give it a go, drag out that whiteboard !!

It could very well be you have a scenario whereby an index rebuild would be a cost effective and worthwhile thing to perform. But unless they give you more than "hint at a possible performance improve", then I would be somewhat sceptical of any such claim.

Some thoughts.

Cheers

Richard Received on Wed May 05 2004 - 08:56:47 CDT

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