Global variables stay active while the QMF instance (session) is active, or stay active permanently by updating the Windows registry. Substitution variables, however, stay active only during execution of the object.
Global variables are associated with QMF for Windows and the operating system's registry (if you update the registry to make global variables permanent). Substitution variables are associated with QMF objects.
Because global variables are active while QMF for Windows is active, the variables will have the same value until the instance of QMF for Windows is finished. The global variable can be accessed by all QMF objects. Different instances of QMF cannot see the global variables for another instance.
There are two types of global variables:
A global variable can be used in a query, form, or procedure. You can update global variables by selecting View--> Global Variables.
The global variables provided by QMF for Windows are stored in the Windows registry. The system administrator can view and edit the system global variables before installation. Global variables can be exported to all users by copying the variables from one system to another after installation to keep the variables in sync. The global variables are located in the following path in the Registry:
HKEY_CURRENT_USER\SOFTWARE\IBM\RDBI\GlobalVariables