Re: Remove xmin and cmin from frozen tuples

Jim C. Nasby <jnasby@pervasive.com>

From: "Jim C. Nasby" <jnasby@pervasive.com>
To: Bruce Momjian <pgman@candle.pha.pa.us>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, ITAGAKI Takahiro <itagaki.takahiro@lab.ntt.co.jp>, pgsql-hackers@postgresql.org
Date: 2005-09-06T20:58:28Z
Lists: pgsql-hackers
On Fri, Sep 02, 2005 at 03:51:15PM -0400, Bruce Momjian wrote:
> 	  One possible solution is to create a phantom cid which represents a
> 	  cmin/cmax pair and is stored in local memory.

If we're going to look at doing that I think it would also be good to
consider including xmin and xmax as well. This might require persisting
to disk, but for transactions that touch a number of tuples it could
potentially be a big win (imagine being able to shrink all 4 fields down
to a single int; a 45% space reduction).
-- 
Jim C. Nasby, Sr. Engineering Consultant      jnasby@pervasive.com
Pervasive Software      http://pervasive.com    work: 512-231-6117
vcard: http://jim.nasby.net/pervasive.vcf       cell: 512-569-9461