In Germany the interviewers notes and all the other documents related to the candidate have to be destroyed when they are not needed any more
(Datensparsamkeit, literally data austerity, officially data reduction and data economy).<p>When a candidate is rejected there is period of to months they can sue for discrimination. After that one additional month is considered to be justifiable.
So everything has to be destroyed three months after the rejection letter if there is no discrimination case.