On Thursday, September 18, 2003, at 12:11 PM, Lamar Owen wrote:
>
> RTA. It's been hashed, rehashed, and hashed again. I've asked twice
> if eRserver can replicate a 7.3 database onto a 7.4 server (or a 7.2
> onto a 7.3); that question has yet to be answered. If it can do this,
> then I would be a much happier camper. I would be happy for a
> migration tool that could read the old format
> _without_a_running_old_backend_ and convert it to the new format
> _without_a_running_backend_. That's always been my beef, that the new
> backend is powerless to recover the old data. OS upgrades where
> PostgreSQL is part of the OS, FreeBSD ports upgrades (according to a
> user report on the lists a few months back), and RPM upgrades are
> absolutely horrid at this point. *You* might can stand it; some > cannot.
>
eRserver should be able to migrate the data. If you make heavy use of
sequences, schemas and other such things it won't help you for those.
Its not a bad idea to do it that way, if you aren't dealing with large
or very complex databases. The first thing its going to do when you add
a slave is do a dump/restore to create the replication target. If you
can afford the disk space and time, that will migrate the data. By
itself that isn't any different than doing that by hand. Where eRserver
may help is keeping the data in sync while you work the other things
out.
Sequences and schemas are the two things it doesn't handle at the
moment. I've created a patch and some new client apps to manage the
schema part, but I haven't had the chance to send them off to someone
to see if they'll fit in. Sequences are on my list of things to do
next. Time time time time.....
Using eRserver may help you work around the problem, given certain
conditions. It doesn't solve it. I think if we can get Mr. Drake's
initiative off the ground we may at least figure out if there is a
solution.
--------------------
Andrew Rawnsley
President
The Ravensfield Digital Resource Group, Ltd.
(740) 587-0114
www.ravensfield.com
