On Suse-Linux you have gzipped backups of the rpmdb: https://www.novell.com/documentation/suse91/suselinux-adminguide/html/ch02s03.html#sec:rpm.anfragen
But how can I get the list of all installed packages from this file?
If I unzip it, it is this file type:
file Packages-20160323 Packages-20160323: Berkeley DB (Hash, version 8, native byte-order)
rpm --dbpath but this options wants a directory and not a berkley-db-file....