Using Actuate BIRT Viewers : Performing calculations in a report : Creating a custom expression : Using numbers and dates in a custom expression : How to add days to an existing date value
 
How to add days to an existing date value
To create a column that displays date values that are greater than the date values in another column, complete the following steps.
1 Select a column. From the context menu, choose ColumnChoose New Computed Column. New Computed Column appears.
2 In Column Label, type a name for the calculated column. For example, type Forecast Shipping Date.
3 In Enter Expression, type the letter A. A list appears, displaying functions that begin with A.
4 Choose ADD_DAY(date, daysToAdd).
5 For the first argument, type a left bracket ([) and select the date column from the list. For example, select Order Date.
6 For the second argument, type the number of days to add. In this case, type 7.
7 Validate the expression and choose OK. The calculated column appears in the report. For every value in the Order Date column, the calculated column displays a date seven days later than the order date.