From: Scott Cain <cain@cshl.org>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Jan Wieck <JanWieck@Yahoo.com>
Cc: PgSQL Performance ML <pgsql-performance@postgresql.org>
Cc: pgsql-sql@postgresql.org
Subject: Re: [SQL] EXTERNAL storage and substring on long strings
Date: 14 Aug 2003 14:11:07 -0400
Message-ID: <1060884667.1430.6.camel@localhost.localdomain> (raw)
In-Reply-To: <6311.1060884021@sss.pgh.pa.us>
References: <1059679600.1429.41.camel@localhost.localdomain>
<3F297CBA.1080703@joeconway.com>
<1059686498.7505.558.camel@haggis>
<1060010735.1433.26.camel@localhost.localdomain>
<3574.1060012423@sss.pgh.pa.us>
<3F3BA49D.9070405@Yahoo.com>
<6311.1060884021@sss.pgh.pa.us>
Agreed. When I actually Did It Right (tm), EXTERNAL storage gave
similar (probably better) performance as my shredding method, without
all the hoops to breakup and reassemble the string.
Scott
On Thu, 2003-08-14 at 14:00, Tom Lane wrote:
> Jan Wieck <JanWieck@Yahoo.com> writes:
> > Doesn't look that unrealistic to me. A plain text based substring
> > function will reassemble the whole beast first before cutting out the
> > wanted part. His manually chunked version will read only those chunks
> > needed.
>
> So does substr(), if applied to EXTERNAL (non-compressed) toasted text.
> See John Gray's improvements a release or two back.
>
> regards, tom lane
--
------------------------------------------------------------------------
Scott Cain, Ph. D. cain@cshl.org
GMOD Coordinator (http://www.gmod.org/) 216-392-3087
Cold Spring Harbor Laboratory
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: pgsql-sql@postgresql.org
Cc: cain@cshl.org, tgl@sss.pgh.pa.us, JanWieck@Yahoo.com, pgsql-performance@postgresql.org
Subject: Re: [SQL] EXTERNAL storage and substring on long strings
In-Reply-To: <1060884667.1430.6.camel@localhost.localdomain>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox