The issue: Currently when SDM experiences a connection loss to database, it can detect this and log it to stdlog. It will try to reconnect for a while, but after a period of time it gives up and after that the system is not functioning anymore. As far as I know restarting the system is the only way to recover from this after the time limit is reached. This might have been patched on later releases, but it doesn't nullify the suggestion described below.
Suggestion: Add an option to immediately go to read-only mode when DB connection loss is detected and show an error to users if they try to go to edit mode (or do anything that requires a check-out of an object). In my point of view this is less disruptive to the users than have them think their saves are OK and then finding data loss after a possible restart of the system. Obviously the write-mode is restored if the connection gois back up. The read-only mode would be activated also when the virtual DB connection is lost. In other words, if any link between the object layer and RDBMS is failing.
Feel free to comment below if I've overlooked something.