For environments running version 9.3 and below : (To know the database used, check the file named databaseinfo under <Servicedeskplus-Home>/server/default/conf folder)
For environments running version 10.5 and above : (To know the database used, check the file named database_params.conf under <Servicedeskplus-Home>/conf folder)
Or, Invoke changeDBServer.bat or changeDBServer.sh file from <Servicedeskplus-Home>\bin Directory.