
> I still think there must be sorting going on, as the result 
> is returned
> instantly if you remove the ORDER BY. I don't know - I do think it's
> much better now.

Are you doing the exact query I wrote for you ?
That is:
	order by mail_list desc, mail_date desc

explain should tell you if it does a sort. There should not be a difference
with 
or without the order by.
Hiroshi, I think you implemented the backwards index scan ?
Otherwise he would need to recreate the index as
 (mail_list desc, mail_date desc)

Sorry for the inconvenience
Andreas

Thu, 13 Jul 2000 09:11:30 +0200
Zeugswetter Andreas SB <ZeugswetterA@wien.spardat.at>
AW: Some Improvement
> -----Original Message-----
> From: pgsql-hackers-owner@hub.org [mailto:pgsql-hackers-owner@hub.org]On
> Behalf Of Zeugswetter Andreas SB
> 
> > I still think there must be sorting going on, as the result 
> > is returned
> > instantly if you remove the ORDER BY. I don't know - I do think it's
> > much better now.
> 
> Are you doing the exact query I wrote for you ?
> That is:
> 	order by mail_list desc, mail_date desc
> 
> explain should tell you if it does a sort. There should not be a 
> difference
> with 
> or without the order by.
> Hiroshi, I think you implemented the backwards index scan ?

Yes,but I didn't implement backwards index path for cost estimate.

Regards.

Hiroshi Inoue
Inoue@tpf.co.jp

Thu, 13 Jul 2000 16:45:57 +0900
"Hiroshi Inoue" <Inoue@tpf.co.jp>
RE: Some Improvement
"Hiroshi Inoue" <Inoue@tpf.co.jp> writes:
>> Hiroshi, I think you implemented the backwards index scan ?

> Yes,but I didn't implement backwards index path for cost estimate.

I did ... but I didn't get it quite right :-( ... see later message ...

			regards, tom lane

Thu, 13 Jul 2000 04:07:52 -0400
Tom Lane <tgl@sss.pgh.pa.us>
Re: Some Improvement 