Working behind the scenes of the package manager is the RPM database, stored in . It uses Berkeley DB as its back-end. It consists of a single database () containing all of the meta information of the installed RPMs. Multiple databases are created for indexing purposes, replicating data to speed up queries. The database is used to keep track of all files that are changed and created when a user (using RPM) installs a package, thus enabling the user (via RPM) to reverse the changes and remove the package later. If the database gets corrupted (which is possible if the RPM client is killed), the index databases can be recreated with the command.
