Can I clear statistics?

[Kathey Marsden <km...@sbcglobal.net>]

If I update (enable) statistics  on a table and then find performance is 
worse or decide it is not worth the trouble having to update them 
periodically, is there a way to clear statistics so that I can go back 
to the original plan selection or am I committed to using statistics and 
updating periodically once I update them once?

Thanks

Kathey

Re: Can I clear statistics?

[Kathey Marsden <km...@sbcglobal.net>]

Mamta Satoor wrote:
> Currently, there is no way to drop the statistics neither is there an
> optimizer override 
Thanks Mamta,

I filed DERBY-4115 to request the ability to drop statistics and 
DERBY-4113 for the optimizer override.  I'll update my doc comments to 
provide a warning to users that they are committed to using and updating 
statistics if their data changes once the update has been performed.

Kathey

Re: Can I clear statistics?

[Mamta Satoor <ms...@gmail.com>]

Currently, there is no way to drop the statistics neither is there an
optimizer override I think to say do not look at the statistics. But
hopefully other optimizer overrides can help tweak the query plan for
an experienced user.

Mamta

On Tue, Mar 24, 2009 at 5:58 AM, Kathey Marsden
<km...@sbcglobal.net> wrote:
> If I update (enable) statistics  on a table and then find performance is
> worse or decide it is not worth the trouble having to update them
> periodically, is there a way to clear statistics so that I can go back to
> the original plan selection or am I committed to using statistics and
> updating periodically once I update them once?
>
> Thanks
>
> Kathey
>
>