Editing Assignment Expressions
You can define and edit the assignment expression associated with an assignment as described in this section.
To edit an assignment expression:
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1. If necessary, click on the Assignments tab to make it the active tab.
2. In the Assignments pane, select the assignment whose assignment expression you want to edit.
3. In the Properties pane, double-click on the Assignment cell to open the Assignment Expression dialog.

To open the Assignment Expression dialog, you can also click the browse button (…) on the far right of the Assignment cell.
4. Enter the assignment expression using the keyboard and the toolbar buttons to enter values, measurements, field names, attribute names, qualifier names, lookup values, attribute text values, operators, and functions.

You do not need to specify the field to which MDM assigns the expression result, which is automatically assigned to the field specified by the Assignment Field property of the assignment in the Assignments tab.
5. Click OK to close the Assignment Expression dialog.
6. To save the assignment, right-click on the Properties pane and choose Save Assignment from the context menu, or press Shift+Enter.
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