Re: index columns

From: Stefan Koehler <contact_at_soocs.de>
Date: Sat, 18 Apr 2015 00:44:29 +0200 (CEST)
Message-ID: <433162939.93791.1429310669743.JavaMail.open-xchange_at_app01.ox.hosteurope.de>

Hi Orlando,
oh a classic oldie and common myth :-))

I think the only source i need to point to is Richard Foote's blog post about this: - https://richardfoote.wordpress.com/2008/02/13/its-less-efficient-to-have-low-cardinality-leading-columns-in-an-index-right/ - https://richardfoote.wordpress.com/2008/02/15/clustering-factor-a-consideration-in-index-lead-column-decision-sweet-thing/

Best Regards
Stefan Koehler

Freelance Oracle performance consultant and researcher Homepage: http://www.soocs.de
Twitter: _at_OracleSK  

> Orlando L <oralrnr_at_gmail.com> hat am 18. April 2015 um 00:02 geschrieben:
>
> All
>
> My colleague and I got into a discussion about indexes. I feel that putting the most selective column first while creating multi column indexes is
> the correct approach, followed by second most selective column as the second column in the index and so on. My colleague feels that the order does
> not matter. Can someone clarify.
>
> OL
 

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Received on Sat Apr 18 2015 - 00:44:29 CEST