Re: stats document links.

From: Niall Litchfield <niall.litchfield_at_gmail.com>
Date: Wed, 23 Mar 2011 15:59:11 +0000
Message-ID: <AANLkTi=AZzNJpvWt8O5QFP7kmmoJYmvDAywd1JLGaiMe_at_mail.gmail.com>

On Wed, Mar 23, 2011 at 4:18 AM, Greg Rahn <greg_at_structureddata.org> wrote:

> If the data has not changed or significantly changed, then there is no
> reason to regather unless one wants to appear productive and burn up
> system resources :)
>
> http://structureddata.org/2008/03/26/choosing-an-optimal-stats-gathering-strategy/
>
>

The most common reason for object stats significantly changing that I come across is the use of date (or sequence based) columns in queries. (or people that arbitrarily delete a third of their data to see if it will aid performance ). GATHER_STALE will deal with this, but I must admit I'd like the ability to tell oracle that 5% (or 50%) change made things stale instead of a fixed (undocumented if you use the default job) parameter. If anyone incorrectly picks arbitrary values on my database it should be me!

-- 
Niall Litchfield
Oracle DBA
http://www.orawin.info

--
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Received on Wed Mar 23 2011 - 10:59:11 CDT