RE: UncompBkts: what is it? (reference to 10053 trace)

Charles,  

You may consider Steve Adams' consider_histograms.sql script, available here:
http://ixora.com.au/scripts/query_opt.htm  

-Mark
 

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Mark J. Bobak
Senior Oracle Architect
ProQuest Information & Learning

Ours is the age that is proud of machines that can think and suspicious of men who try to. --H. Mumford Jones, 1892-1980  

From: oracle-l-bounce_at_freelists.org
[mailto:oracle-l-bounce_at_freelists.org] On Behalf Of Schultz, Charles Sent: Thursday, July 27, 2006 4:15 PM
To: oracle-l_at_freelists.org
Subject: UncompBkts: what is it? (reference to 10053 trace)

Google did not deign to tell me, so I am looking elsewhere.

In somewhat related terms, is there a set mathematical formula for "data skew"? Folks talk about a "little skew" or "very skewed" data. Practically any column is going to have at least some skew, but I have to assume that there is a threshold whereby a given histogram (ie, insufficient number of buckets) is going to hurt your performance.

charles schultz
oracle dba
aits - adsd
university of illinois

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http://www.freelists.org/webpage/oracle-l Received on Thu Jul 27 2006 - 16:37:26 CDT