From: DeskNow Knowledge Base
http://www.desknow.com/kb/

How do I tell which database is used by DeskNow?
http://www.desknow.com/kb/idx/12/120/article/

To find out which database you're using: open the C:\desknowdata\cfg\Database.cfg (/var/desknowdata/cfg/Database.cfg) file, and look at the Url parameter (NB if you find a line preceded by a #, it is commented out, and should be ignored. The file will contain only one line beginning with 'Url').

If you do not have access to the Database.cfg file

Simply open the log.Init file from the day that DeskNow was last started.

You will see a line like 'Database driver: ' and the name of the database driver.

This will confirm you which db driver (and so database) DeskNow is using.