Re: pg_upgrade (was: 8.2 features status)

On Fri, Aug 04, 2006 at 02:12:16PM -0400, Stephen Frost wrote:
> * Jim C. Nasby (jnasby@pervasive.com) wrote:
> > On Thu, Aug 03, 2006 at 11:20:48PM -0700, Josh Berkus wrote:
> > > > * In-place upgrades (pg_upgrade)
> > > 
> > > BTW, I may get Sun to contribute an engineer for this; will get you posted.
> > 
> > How would such a thing handle changes to page formats?
> 
> Couldn't this be done by converting a table/partial-table at a time?
> It wouldn't be something which could run while the system is live, but
> it'd probably take less time than dump/restore and wouldn't require
> double the disk space of the whole database... no?

True, but if you're going to go about creating code that can deal with 2
different versions of on-disk data, why not go one better: put that code
into the database itself, so that pages are converted on-the-fly as
they're dirtied. That way you have *no* downtime (or almost no, anyway).
-- 
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