To: K C Lau <kclau60@netvigator.com>
Cc: Simon Riggs <simon@2ndquadrant.com>,
	pgsql-performance@postgresql.org
Subject: Re: SELECT LIMIT 1 VIEW Performance Issue 
In-reply-to: <6.2.1.2.0.20050922221846.02c45fb8@localhost> 
References: <6.2.1.2.0.20050615100524.04f9d6a8@localhost>
	<6.2.1.2.0.20050922102035.07bcf2e0@localhost>
	<1127378456.4145.76.camel@localhost.localdomain>
	<6.2.1.2.0.20050922181009.02c36ca8@localhost>
	<1127393284.4145.109.camel@localhost.localdomain>
	<6.2.1.2.0.20050922221846.02c45fb8@localhost>
Comments: In-reply-to K C Lau <kclau60@netvigator.com>
	message dated "Thu, 22 Sep 2005 22:39:29 +0800"
Date: Thu, 22 Sep 2005 11:41:14 -0400
Message-ID: <29336.1127403674@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>

K C Lau <kclau60@netvigator.com> writes:
> At 20:48 05/09/22, Simon Riggs wrote:
>> Even if this were fixed for 8.1, which seems unlikely, would you be able
>> to move to that release immediately?

> Yes. In fact when we first developed our system a few years ago, we tested 
> on MS7.0, Oracle 8 and PG 7.1.1 and we did not hit that problem.

It's really not credible that PG 7.1 did any better with this than
current sources do.  The subplan mechanism hasn't changed materially
since about 6.5.  It could be that 7.1's performance was simply so
bad across the board that you didn't notice ...

			regards, tom lane