Ever got an error like this and don't know how to solve it?
[david.ward@install02 /var/lib/rpm]$ sudo rpm -qa|grep rpm rpmdb: Program version 4.3 doesn't match environment version error: db4 error(-30974) from dbenv->open: DB_VERSION_MISMATCH: Database environment version mismatch error: cannot open Packages index using db3 - (-30974) error: cannot open Packages database in /var/lib/rpm
Well the solution is simply, as root:
rm /var/lib/rpm/__* && rpm --rebuilddb