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index selectivity when histograms presents on the column

From: The Human Fly <sjaffarhussain_at_gmail.com>
Date: Tue, 21 Mar 2006 18:57:54 +0300
Message-ID: <97b7fd2f0603210757x621f3d8flbdf34e12ddebc997@mail.gmail.com>


List,

Can anyone tell me the index selectivity formula for a column when there are histograms on the column.
I know that the index selectivity without histograms is = num_distinct/num_rows and also know that table selectivity uses density to calculate the selectivty when there are histograms placed on the column.

Thanks,
--

Best Regards,
Syed Jaffar Hussain
8i,9i & 10g, OCP DBA
Banque Saudi Fransi,
Saudi Arabia
http://jaffardba.blogspot.com/



"Winners don't do different things. They do things differently."
--

http://www.freelists.org/webpage/oracle-l Received on Tue Mar 21 2006 - 09:57:54 CST

Original text of this message

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