Enterprise Vault MDC and DB files

I've done some google and symantec community searching,without much specific luck in finding what I need so I figured I would  ask here myself.

I am looking for information on the MDC and DB files created by Enterprise Vault. Specifically what they contain\do not contain, how they are related to each other, under what circumstances are each created. That sort of thing.

Any help\pointers anyone can provide would be fantastic

Thanks much

MT