how to create gdg in mainframe?
['JCL to create a new Generation of a GDG. ... ', 'When NOEMPTY is coded. ... ', 'When EMPTY is coded. ... ', 'Example to refer the current Generation and previous Generation in JCL. ... ', 'JCL to change the properties of a GDG - Alter GDG Base. ... ', 'Delete GDG using IDCAMS utility.']