Editing Expressions
You can define and edit the expression associated with a validation, an assignment, or a calculated field as described in this section.
To edit an expression:
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1. Double-click on the expression cell to open the applicable expression dialog.

To open the expression dialog, you can also click the browse button (…) on the far right of the expression cell.
2. Enter the 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.
3. Click OKto close the expression dialog.
4. To save the expression, right-click on the properties pane and choose Save Expression from the context menu, or press Shift + Enter.