Re: Question about DBMS_STATS and Histograms

From: Sybrand Bakker <gooiditweg_at_nospam.demon.nl>
Date: Thu, 08 May 2003 00:32:50 +0200
Message-ID: <la2jbv0303b6ph87jag0le7o0s77d2frqc@4ax.com>

On 7 May 2003 14:42:36 -0700, JusungYang_at_yahoo.com (Jusung Yang) wrote:

>rgaffuri_at_cox.net (Ryan Gaffuri) wrote in message news:<1efdad5b.0305060637.1334f3ca_at_posting.google.com>...
>> I checked on Asktom and I understand how histograms work and what they
>> are from college level statistics. However, Im having trouble
>> calculating my 'N' buckets. Anyone have a short and dirty method for
>> estimating this or a link to one? Couldn't find any general rules of
>> thumb on Asktom.
>>
>> Ryan
>
>A bit of correction to my previous post... I meant to say
>"value-based" histograms. The term "Height-balanced histograms" makes
>sense. "Value-balanced" does not seem to make much sense, however.
>
>- Jusung Yang

Anyway I noticed the optimizer doesn't create redundant buckets. If you specify 250 buckets, and two is sufficient you get 2. That said I'm tempted to specify the maximum always.

Sybrand Bakker, Senior Oracle DBA

To reply remove -verwijderdit from my e-mail address Received on Wed May 07 2003 - 17:32:50 CDT