Received: from localhost (postgresql.org [64.49.215.8])
	by postgresql.org (Postfix) with ESMTP id A206047549E
	for <pgsql-sql@postgresql.org>; Fri,  9 Aug 2002 09:56:05 -0400 (EDT)
Received: from smaug.securitymatrix.com (unknown [64.238.98.87])
	by postgresql.org (Postfix) with ESMTP id D669447546C
	for <pgsql-sql@postgresql.org>; Fri,  9 Aug 2002 09:56:04 -0400 (EDT)
Received: from kaos.securitymatrix.com (kaos.securitymatrix.com
 [172.16.0.101])
	by smaug.securitymatrix.com (8.11.6/8.11.6) with ESMTP id g79DvvW04441;
	Fri, 9 Aug 2002 09:58:07 -0400
Subject: Re: Table Sorting and Limit Question
From: Dawn Hollingsworth <dmh@airdefense.net>
To: Ludwig Lim <lud_nowhere_man@yahoo.com>
Cc: PosgreSQL Mailing List <pgsql-sql@postgresql.org>
In-Reply-To: <20020809014223.3100.qmail@web40009.mail.yahoo.com>
References: <20020809014223.3100.qmail@web40009.mail.yahoo.com>
Content-Type: text/plain
Content-Transfer-Encoding: 7bit
X-Mailer: Ximian Evolution 1.0.8 
Date: 09 Aug 2002 09:55:24 -0400
Message-Id: <1028901334.1423.18.camel@kaos>
Mime-Version: 1.0
X-Virus-Scanned: by AMaViS new-20020517
X-Archive-Number: 200208/163
X-Sequence-Number: 9009


Since the id is a sequence type it should be unique. In this case it
also happens to be my primary key into this table which will also make
it unique. So the query below would only return 1 row. 

The part I'm missing is the offset number of the limit. Is there any way
to figure out which offset into the query would contain the id I'm
interested in.

Dawn Hollingsworth 
Principal Engineer 
AirDefense, Inc.


On Thu, 2002-08-08 at 21:42, Ludwig Lim wrote:
> 
> --- Dawn Hollingsworth <dmh@airdefense.net> wrote:
> > 
> > 
> > Currently we have a table with a sequence number( id
> > ) as a primary key,
> > a date field which is indexed and several other
> > columns. The user
> > interface allows the user to sort the data by date
> > and limits the result
> > set to 100 rows. 
> > 
> > The question is: 
> > The user interface needs the capability to sort the
> > table by date but
> > pull out the hundred row set that contains id
> > say...542 for example. 
> > 
> > What would be the best way to do this taking into
> > account this table is
> > several hundred thousand rows? 
> 
> try also to index the id.
> 
> Try :
> Select *
> from <table>
> where id=<id>
> order by date
> limit <limit no>
> 
> In this case you <limit no> is 100 since you want to
> return at most 100 rows.
> 
> hope that helps.
> 
> ludwig.
> 
> 
> __________________________________________________
> Do You Yahoo!?
> HotJobs - Search Thousands of New Jobs
> http://www.hotjobs.com
> 
> ---------------------------(end of broadcast)---------------------------
> TIP 1: subscribe and unsubscribe commands go to majordomo@postgresql.org