Date: Tue, 19 Jul 2005 21:14:04 +0200
To: "Oliver Crosby" <ryusei@gmail.com>,
	"Richard Huxton" <dev@archonet.com>
Subject: Re: Looking for tips
Cc: pgsql-performance@postgresql.org
References: <1efd553a05071910427b290203@mail.gmail.com>
	<42DD420C.2010306@archonet.com>
	<1efd553a05071911413e50ea90@mail.gmail.com>
From: PFC <lists@boutiquenumerique.com>
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	I can't say wether MySQL is faster for very small queries (like  
SELECT'ing one row based on an indexed field).
	That's why I was asking you about the language...

	I assume you're using a persistent connection.
	For simple queries like this, PG 8.x seemed to be a lot faster than PG  
7.x. Have you tried 8 ?
	I was asking you which language, because for such really small queries  
you have to take into account the library overhead. For instance, in PHP a  
simple query can be 10 times slower in Postgres than in MySQL and I  
believe it is because php's MySQL driver has seen a lot of optimization  
whereas the postgres driver has not. Interestingly, the situation is  
reversed with Python : its best postgres driver (psycopg 2) is a lot  
faster than the MySQL adapter, and faster than both php adapters (a lot  
faster).

	The same query can get (this is from the back of my head):

PHP+Postgres		3-5 ms
Python+MySQL	1ms
PHP+MySQL		0.5 ms
Python+Postgres	0.15 ms

And yes, I had queries executing in 150 microseconds or so, this includes  
time to convert the results to native python objects ! This was on a loop  
of 10000 times the same query. But psycopg2 is fast. The overhead for  
parsing a simple query and fetching just a row is really small.

This is on my Centrino 1.6G laptop.