Encrypting a database with a new encryption key is a time-consuming process because it involves encrypting all of the existing data in the database with the new encryption key. If the process is interrupted before completion, all the changes are rolled back the next time the database is booted. If the interruption occurs immediately after the database is encrypted with the new encryption key but before the connection is returned to the application, you might not be able to boot the database with the old encryption key. In these rare circumstances, you should try to boot the database with the new encryption key.
To encrypt a database with a new encryption key: