Using Actuate BIRT Viewers : Functions and operators : DIFF_DAY( )
 
DIFF_DAY( )
Calculates the number of days between two date values.
Syntax
DIFF_DAY(date1, date2)
Arguments
date1
The first date or date expression to use in the calculation.
date2
The second date or date expression to use in the calculation.
Returns
The number of days between date1 and date2.
Example
The following example calculates the number of days between each value in the invoiceDate data field and each value in the paymentDate data field. The results show how long it takes to pay invoices.
DIFF_DAY([invoiceDate],[paymentDate])
The following example calculates the number of days from an order date to Christmas:
DIFF_DAY([orderDate], "12/25/08")
The following example calculates the number of days from the current date to Christmas. TODAY( ) is a function that returns the current date.
DIFF_DAY(TODAY(), "12/25/08")