The repository database stores all Task details and schedules so it's very much a matter of life-and-death to keep the QVPR in good shape.
The choice between XML and RDBMS as storage method is yours. XML is easier and provides a highly accessible repository but management requires a bit more effort. Storing the repository in a DB has a higher set-up cost, but comes with additional advantages like automatic backups and QlikView platform isolation (for example, reinstalling QVS has no impact on the repository)
