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Home -> Community -> Mailing Lists -> Oracle-L -> Cardinality of indexed columns... how to discover? What is the ma
I'm constantly finding, in the database that I'm developing/supporting,
b-tree indexes on columns with low-cardinality. I generally re-create said
index as a bitmap; however I'd like to go through the entire db and identify
these cases proactively. Is there a way to determine the cardinality of an
index's columns via the dictionary? Also, what recommendations do you have
for determining the cardinality percentage that indicates when a bitmap
should be used? 10%? 20%?
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Author: Jeremy Pulcifer
INET: Jeremy.Pulcifer_at_kadiri.com
Fat City Network Services -- 858-538-5051 http://www.fatcity.com San Diego, California -- Mailing list and web hosting services ---------------------------------------------------------------------To REMOVE yourself from this mailing list, send an E-Mail message to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing). Received on Fri Dec 20 2002 - 13:56:26 CST
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