Re: How to make query avoid using histograms

On 4/26/05, Lex de Haan <lex.de.haan@xxxxxxxxxxxxxx> wrote:
> you can't -- if histograms are available, they will be used.
> of course, you can use various hints and/or session settings
> to influence the optimizer.
> just out of curiosity: why would you, in the presence of histograms,
> ever want to tell the optimizer *not* to use them?

Because you issue a report with bind variables that for 99% of its
executions *should* use histograms, but for 1% of them - the report to
the board say, shouldn't use the execution path generated with
histograms, and bind variable peeking isn't in operation. I don't
think this applies to 9204 though.

--=20
Niall Litchfield
Oracle DBA
http://www.niall.litchfield.dial.pipex.com
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