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How to calculate Selectivity and Skew [message #65504] Fri, 08 October 2004 08:36 Go to next message
gurinder
Messages: 16
Registered: September 2004
Junior Member
How can we calculate the selectivity of an Index and
data is skewed in table or non skewed
Thanx Gurinder

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Re: How to calculate Selectivity and Skew [message #65507 is a reply to message #65504] Fri, 08 October 2004 22:11 Go to previous message
Mahesh Rajendran
Messages: 10708
Registered: March 2002
Location: oracleDocoVille
Senior Member
Account Moderator
Please have a look here.
http://www.akadia.com/services/ora_index_selectivity.html

with dbms_stats there are options to find the skewed columns
please have a look here
http://www.orafaq.com/articles/archives/000018.htm

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