Re: Extremely Low performance with ODBC

I already tried executing them in different order, but that only affects in
just a few milliseconds (the one with explicit joins remains much faster).
The bad news is that I already compared both Explain Analyze results (from
pgAdmin and ODBC) and they follow the same steps. I also tried comparing the
Explain Analyze between the Explicit Join and the Implicit Join, and though
they are different, the Total time is almost the same.

I'll keep on looking for any other differences on different logs.. I think I
already searched all the Postgresql forums I know and no one ever reported
something like that before.

Thanks once again,

Sebastian

-----Mensaje original-----
De: Richard Broersma [mailto:richard(dot)broersma(at)gmail(dot)com]
Enviado el: Martes, 27 de Mayo de 2008 01:14 a.m.
Para: Sebastian Rychter
CC: pgsql-sql(at)postgresql(dot)org
Asunto: Re: [SQL] Extremely Low performance with ODBC

On Mon, May 26, 2008 at 8:26 PM, Sebastian Rychter
<srychter(at)anvet(dot)com(dot)ar> wrote:

> 2008-05-27 02:55:10 GMT LOG: duration: 112157.000 ms statement: SELECT
> 2008-05-27 03:07:29 GMT LOG: duration: 250.000 ms statement: SELECT

Wow, that is a big difference. I reformated your querys and diff'ed
them. You are correct, they are exactly the same query. My only
other guess would be that the first time you execute this query using
ODBC, you need to get a fresh read from disk. However, once this
dataset is cached in memory it returns much faster when you requery it
using PGAdmin. If you run the same query twice conseqitively in ODBC,
does the second query perform much better or do both querys perform
badly?

If they both odbc queries perform badly, the last thing that I would
try would be to capture the results of :

EXPLAIN ANALYZE SELECT ...(your query), from both ODBC, and PGADMIN.
If we compare them It should at least tell us what the server is doing
differently that is causing the query mis-behavior.

--
Regards,
Richard Broersma Jr.

Visit the Los Angles PostgreSQL Users Group (LAPUG)
http://pugs.postgresql.org/lapug

__________ NOD32 3133 (20080526) Information __________

This message was checked by NOD32 antivirus system.
http://www.eset.com