The following example shows (in bold) how to modify a program with the DATE FORMAT clause to use the automatic date windowing capability.
CBL LIB,QUOTE,NOOPT,DATEPROC(FLAG),YEARWINDOW(-60)
. . .
01 Loan-Record.
05 Member-Number Pic X(8).
05 DVD-ID Pic X(8).
05 Date-Due-Back Pic X(6) Date Format yyxxxx.
05 Date-Returned Pic X(6) Date Format yyxxxx.
. . .
If Date-Returned > Date-Due-Back Then
Perform Fine-Member.
There are no changes to the PROCEDURE DIVISION. The addition of the DATE FORMAT clause on the two date fields means that the compiler recognizes them as windowed date fields, and therefore applies the century window when processing the IF statement. For example, if Date-Due-Back contains 080102 (January 2, 2008) and Date-Returned contains 071231 (December 31, 2007), Date-Returned is less than (earlier than) Date-Due-Back, so the program does not perform the Fine-Member paragraph. (The program checks whether a DVD was returned on time.)