Global variables are used for mapping source elements, mapping functions or constants to target elements. They are declared and used globally for all target elements.
To use a global variable in a mapping activity, you need to map it to a target element. This will successfully execute the global variable when you execute the mapping activity in the process flow.
A global variable differs from a context variable, in the respect that it is available only within the selected mapping activity. Context variables are available in the process designer too.
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Select the global variable that you want to edit or delete and click
icon to display the menu. 
- Select Edit to edit the variable. This displays the selected global variable in Edit mode. You can edit the value of the global variable in the Global Variable Value field. You can also edit the name of the global variable.
Alternately, select Remove to delete the selected variable. This displays a confirmation screen for the delete operation.
- Click Yes to delete the selected variable.
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Map Global Variable to Target Element
Once you have created a global variable, you can map it to a target element.