Must db_name be part of the DDC file filename?

[gabrio]

Hi,
a client of mine has a setup with one primary and two standby databases and is asking if it is safe to rename the DDC part of the DDC file filename.

Must db_name be part of the filename?
Are there any consequences to consider by renaming the files on a up and running system? (apart from altering cron jobs etc)

Cheers,
Gabrio