This dialog appears when you click Column > Add Formula Field on the menu bar of the Query Editor window. It helps you to add formulas into a query to be columns of the query. See the dialog.
The following are details about options in this dialog:
Formulas
Lists all the formulas available to be added to the query.
Expression
Shows expressions of the selected formula.
Add
Adds the selected formula to the query.
Close
Exits the dialog.
Help
Displays this help document.
