C++ Demo C++ Demo is a test application, which ships with OpenLink's WinNT drivers. C++ Demo is used to perform basic connection tests and queries. In fact, if you encounter persistent connection or SQL errors with OpenLink drivers, you want to repeat your tests with C++ Demo. Moreover, OpenLink suggests that you create traces or log files with C++ Demo, when appropriate. Use of this program helps Support staff isolate drivers or applications as the source of some problems.