An important use of the RPM database is software verification.
The database not only tracks what packages are installed, but it also tracks where all their components reside (configuration files, documentation, and so on)
Synopsis:
rpm [options] {package-name}
List of options:
-i: install
-U: upgrade
-F: freshen a pakage to a newer version but do not install it if it is not already present
-e: erase, uninstall a package
-h: display hash marks or progress bar
-v: verbosity
-V: verify
-q: query
usually large, output to a file rpm -qa > packages.txt