I have pushed PostgreSQL 9.0.2 into rawhide, replacing the 8.4.x release
series.
As is usual with PostgreSQL major version updates, 9.0.x won't read
8.4.x's database files. However, this time around there is an option
to not have to dump and reload your database: you can try pg_upgrade
instead. The details are in
/usr/share/doc/postgresql-9.0.2/README.rpm-dist
but the short form is: install postgresql-upgrade and run
"service postgresql upgrade".
This isn't terribly well tested, so if you're running critical data
on rawhide (you aren't, are you?) a traditional-form backup would be
a good thing to make first.
Please let me know of either successful or unsuccessful upgrades.
regards, tom lane