> Thanks Stephane. Is there some place (some article) other > than the Oracle > Manual which deals with this(latest) features on the composite index
Asktom has or had an article on this try (will likely wrap) http://asktom.oracle.com/pls/ask/f?p=4950:8:409221425463834426::NO::F495 0_P8_DISPLAYID,F4950_P8_CRITERIA:5671539468597, For example. I attempt to deal with this, but it may not be great in www.niall.litchfield.dial.pipex.com/OracleMyths.zip basically my point is, the value of indexing a column is how often it is used, not necessarily how selective it is and that advances in access paths (specifically compressed indexes and the index skip scan method) *may* mean that doing the opposite of conventional wisdom makes sense. My guess is that skip scan and compression work best with STATUS type columns. I.E those with very few values which are rarely but sometimes updated, and which exist in OLTP databases. Low cardinality columns in a datawarehouse environment are what bitmap indexes were designed for. Cheers Niall -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: Niall Litchfield INET: [EMAIL PROTECTED] 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: [EMAIL PROTECTED] (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).
