safelly erasing dirs/files

Hello all,

How can I safelly erase (with rm command in Linux) files or dirs
concerning a specific database ?

assuming I whish to elimiante data belonging to database A but I do not
whish to disturb or cause any injury to database B

Is there documentation on how to do this or on what exactly am I erasing
if I remove some specific file or dir.

Thanks

Joao