Unfortunately, the reason we are installing our software on premise is that there cannot be any connections established from the box our software is being installed on and outside world in or out due to our client's security requirements.
On the db front, the box that our software being installed on is not our box and we do not have controlled over it. The box is maintained by our client's system admins. Th DBA's of our client will not be maintaining the database of our software, but they may have access to the box. Essentially, our client has entire access to the OS, box, and network where we are installing our software. I was wondering if they can somehow get access to our database, schema, and data if they have full control of the box and the OS-level root access.