On Mon, Mar 14, 2011 at 10:06 AM, Alexander Pyhalov <alp@rsu.ru> wrote:
> Am I right that on PostgreSQL upgrade to new major version (e.g. from 9.0 to
> 9.1) I'll loose my backups (base backups and wal files will be useless)? So
> to go to past after DB upgrade I had to install old version(9.0), recover
> data and then upgrade DBMS software...
> What is the preferred way to deal with this issue?
Your file-system based backups will be useless (but they probably were
useless to start with, unless you shut down postgres while you took
them).
Your pg_dump generated backups will generally be useful. There have
been occasional cases where an old pg_dump won't load into a current
modern postgres install, but I think there were several major versions
gap in those cases.
My bet is that the dumps from 9.0 will load into 9.1 without issue.
If you are not backing up using pg_dump or some form of replication,
you should reconsider your backup strategy.