This is a feature of JBuilder Professional and Enterprise.
Use this dialog box to add an aggregate function to an SQL query. An aggregate function calculates or retrieves a single, collective numeric value for a column based on each qualifying row in a query rather than retrieving each value separately.
From the list of available columns in the table, select the column you want the aggregate function to operate on.
From the list of aggregate functions, select the function you want to apply to the selected column. You choices are AVG(), MIN(), MAX(), SUM(), and COUNT().
Select this option when you want the aggregate function to operate on unique values only in the selected column. You'll find this option most useful with the COUNT() function; that is, when you want to count the unique values in a column.