How will you refer the very first version of a GDG

giscard · New User Joined: 22 Oct 2003 Posts: 4

How will you refer the very first version of a GDG in a JCL(Provided you dont know the number of Versions created)

mdtendulkar · Active User Joined: 29 Jul 2003 Posts: 237 Location: USA

Hello giscard,

Eg.
PAYROLL Name of the GDG
DSNAME=PAYROLL(0) This week?s generation data set
DSNAME=PAYROLL(-1) Last week?s generation data set
DSNAME=PAYROLL(-2) Generation data set of two weeks ago

To retrieve all generations of a GDG as a single data set, specify the GDG name without a generation number in the DSNAME parameter; this is called a GDG ALL request.

DSNAME=PAYROLL For all generations

To use a GDG ALL request, the DCB attributes and data set organization of all generations must be identical.

For a GDG on tape, when you use a GDG ALL request and specify parallel mounting in the UNIT parameter, the system mounts all volumes of only the first generation. This way you can access the first generation.

For the GDGs on DASD, i am not sure if you can really access ONLY the first version without knowing the GDG LIMIT. Will get back to you on this.

Hope this helps,

Regards

Mayuresh Tendulkar

giscard · New User Joined: 22 Oct 2003 Posts: 4

Hi Mayuresh,

Thanks for your response..but to be honest I haven't got an answer for the question.

Thanks,
Anto.

superk · Posted: Tue Nov 29, 2005 7:53 pm

giscard, are you referring to Versions (which YOU control, so you should always know exactly) or Generations (which the system controls)? There is no such built-in facility in JCL for Generations.

priyesh.agrawal · Posted: Tue Nov 29, 2005 8:33 pm

Hi Superk,

Cant we get total number of generations in a GDG Base by IDCAMS LISTCAT. And then refer the first generation by (-(n-1)) in JCL.

I m not very sure, Please correct, If I wrong.

Regards,

Priyesh.

superk · Posted: Tue Nov 29, 2005 9:27 pm

Absolutely. There have been many posts in this forum that show potential processes.

rohit jaiswal · Posted: Fri Mar 10, 2006 7:04 pm

can anyone give me a jcl and explain me in detail about it

thanks

regards
rohit