How to subtract date values in a calculated column

Using Actuate BIRT Viewers : Performing calculations in a report : Creating a custom expression : Using numbers and dates in a custom expression : How to subtract date values in a calculated column

The following section describes how to display the difference between two date values.

1 Select a column. From the context menu, choose Column➛Choose New Computed Column. New Computed Column appears.

2 In Column Label, type a name for the calculated column. For example, for a calculation that subtracts the actual shipping date from the date requested, type Shipping Delay.

3 In Enter Expression, type the letter d. A list appears, displaying functions that begin with d.

4 Choose DIFF_DAY(date1, date2).

5 For the first argument, type a left bracket ([) and select the first date column from the list. For example, select Date Requested.

6 For the second argument, type a left bracket ([) and select the second date column from the list. For example, select Actual Shipping Date.

7 Validate the expression and choose OK. The calculated column appears in the report, displaying the difference between the two dates.