
If I were loony enough to want to make an attempt at a version updater 
(i.e. migrate a
7.4 database to 8.0 without an initdb), any suggestions on where to 
poke first? Does a
catalog/list of system catalog changes exist anywhere? Any really gross 
problems immediately
present themselves? Is dusting off pg_upgrade a good place to start, or 
is that a dead end?

There any chance of getting something to work at all?

(I figure I made enough of a stink about it last year about this time, 
I should at least make
the attempt...or have one of my minions do it...)

--------------------

Andrew Rawnsley
President
The Ravensfield Digital Resource Group, Ltd.
(740) 587-0114
www.ravensfield.com


Mon, 30 Aug 2004 21:59:47 -0400
Andrew Rawnsley <ronz@ravensfield.com>
version upgrade
Andrew Rawnsley <ronz@ravensfield.com> writes:
> If I were loony enough to want to make an attempt at a version updater
> (i.e. migrate a 7.4 database to 8.0 without an initdb), any
> suggestions on where to poke first?

pg_upgrade is the way to go IMHO.  I would not try to "dust off" the old
shell-script code for it, but start from scratch using the fundamental
ideas.  To wit, migrate the schema using pg_dump and reload, then push
the existing data files into place.  There are enough low-level details
involved that it's better to do this in C than shell code, but the
concept is sound.

This will not work for the 7.4->8.0 transition in particular, because
the data file format changed (heap tuple header changes).  But those
sorts of changes are relatively rare and will probably get rarer
(especially if there's any reason for us to try to avoid 'em).  If you
start now you might have a credible implementation in time for 8.0->8.1
...

			regards, tom lane

Mon, 30 Aug 2004 22:28:59 -0400
Tom Lane <tgl@sss.pgh.pa.us>
Re: version upgrade 