Re: Why isn't Oracle using my index ? <humour>

Just realized that I made a mistake in one of my tests, and had also overlooked a possible 'de-tuning' option.

Current calculation:

    I am confident I could de-tune an Oracle database     so that it chose a tablescan over a single row     access by (enabled, validated) primary key     when the heap table held 740,000,000 rows, and     both table and index had had statistics generated     through: analyze ... compute.

Regards

Jonathan Lewis
http://www.jlcomp.demon.co.uk

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The Co-operative Oracle Users' FAQ
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• Original Message ----- To: "Multiple recipients of list ORACLE-L" <ORACLE-L_at_fatcity.com> Sent: 25 April 2003 02:16

> Was the table analyzed?
> Maybe Oracle won't always choose the index if the query returns less than 0.00000067% (1 in 150 million) rows, but I have full faith that it will do the right thing if the query returns less than 0.0000005% of the rows.
>
> Doesn't your laptop come with some kind of Solitaire program for distraction during airport downtime?
>

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