Re: Slow indexscan

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Mikko,

I don't follow this thread, just see familiar spherical coordinates we
work with a lot. If you need fast radial query you can use our
q3c package available from q3c.sf.net. See some details http://www.sai.msu.su/~megera/wiki/SkyPixelization

Oleg

On Wed, 20 Jun 2007, Tom Lane wrote:

"Mikko Partio" <mpartio@xxxxxxxxx> writes:

 Index Scan using tbl_20070601_pkey on tbl_20070601 t1
(cost=0.00..365.13rows=13 width=137) (actual time=
120.83..10752.64 rows=539 loops=1)
   Index Cond: ((validtime >= 20070602000000::bigint) AND (validtime <=
20070602235500::bigint) AND (latitude = 60.2744::double precision) AND
(longitude = 26.4417::double precision))
   Filter: (parname = 'temperature'::character varying)

You do realize that's going to scan the entire index range from
20070602000000 to 20070602235500?

If this is a typical query you'd be better off putting the lat/long
columns first in the index.

			regards, tom lane

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	Regards,
		Oleg
_____________________________________________________________
Oleg Bartunov, Research Scientist, Head of AstroNet (www.astronet.ru),
Sternberg Astronomical Institute, Moscow University, Russia
Internet: oleg@xxxxxxxxxx, http://www.sai.msu.su/~megera/
phone: +007(495)939-16-83, +007(495)939-23-83


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