Message-ID: <3F2EC244.9040107@joeconway.com>
Date: Mon, 04 Aug 2003 13:29:56 -0700
From: Joe Conway <mail@joeconway.com>
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To: Scott Cain <cain@cshl.org>
Cc: Tom Lane <tgl@sss.pgh.pa.us>,
	PgSQL Performance ML <pgsql-performance@postgresql.org>,
	pgsql-sql@postgresql.org
Subject: Re: [SQL] EXTERNAL storage and substring on long strings
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Scott Cain wrote:
> On Mon, 2003-08-04 at 11:53, Tom Lane wrote:
>>I find it really, really hard to believe that a crude reimplementation
>>in plpgsql of the TOAST concept could beat the built-in implementation
>>at all, let alone beat it by two orders of magnitude.
>>
>>Either there's something unrealistic about your testing of the
>>dna_string function, or your original tests are not causing TOAST to be
>>invoked in the expected way, or there's a bug we need to fix.  I'd
>>really like to see some profiling of the poor-performing
>>external-storage case, so we can figure out what's going on.
> 
> I was really hoping for a "Good job and glad to hear it" from you :-)
> 
> I don't think there is anything unrealistic about my function or its
> testing, as it is very much along the lines of the types of things we do
> now.  I will really try to do some profiling this week to help figure
> out what is going on.

Is there a sample table schema and dataset available (external-storage 
case) that we can play with?

Joe