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Re: QUERY REG DELETE GDG

PostPosted: Thu Nov 25, 2010 8:54 pm
by Akatsukami
expat wrote:
shabukumar wrote:But Whenever a GDS is created, a retention period was automatically recorded for the same by MVS. On that retention period the GDS will be deleted automatically.
Kindly let me clarify If I am wrong.

I have never seen a retention period set as default to GDS. In fact when I set up an SMS environment any user specified retention periods are just ignored.

I think that you will also find that a GDS will still be retained even if a retention period was permitted so long as it remains cataloged, even after said retention period has expired.

Once again, let me point out that this is not true of all shops. It is not true of my current shop. It' may well be a superior way of doing things...but I think that the existence of these fora is more than sufficient evidence that to most junior programmers these days, "superior" is only a meaningless noise :evil:

Re: QUERY REG DELETE GDG

PostPosted: Thu Nov 25, 2010 9:41 pm
by steve-myers
shabukumar wrote:... But Whenever a GDS is created, a retention period was automatically recorded for the same by MVS. On that retention period the GDS will be deleted automatically.
I've never heard of such a thing.

Tape management systems often have a feature to "scratch" a tape when the data set on the tape gets uncatalogued, and this is often applied to GDG data sets on tape. Tape management systems often apply a default retention period when a tape is created, but this has noting to do with the data set being a GDG.

A method to apply an expiration date (but not a retention period) is to apply the expiration date (perhaps as a retention period) to the model DSCB used when creating a generation data set.

Re: QUERY REG DELETE GDG

PostPosted: Sat Nov 27, 2010 12:47 pm
by shabukumar
Thanks Expat,

I understood. But still have few clarification.

DELETE GDG FORCE deletes GDG and its generation.

DELETE GDG PURGE deletes GDG and its generation by overriding the retention period.

But even FORCE is also doing the same regardless of retention period.

As you told, even after the expiration of retention period, it still remains catalogued, we have to use DELETE GDG FORCE to delete the GDG.

But before the expiration of retention period, Using Force will delete the GDG same as PURGE.

So, Request you to let me clarify how FORCE differs from PURGE.

Re: QUERY REG DELETE GDG

PostPosted: Sat Nov 27, 2010 1:31 pm
by enrico-sorichetti
reposting the same things over and over will not help You understand things
the explanation has already been given together with a link to the manuals

as a trainer ( that' s what You told us ) You should know when enough is enough
and when an unresponsive pupil should be be flunked

meditate, please, meditate

Re: QUERY REG DELETE GDG

PostPosted: Sun Nov 28, 2010 11:03 am
by shabukumar
Pardon me Enrico,

I have not seen page 2 before posting. So I replied to expat which I feel like the last post was like the message posted by him as shown in page 1.

Right now I seen page 2. Kindly let me go through it and reply you shortly.

Re: QUERY REG DELETE GDG

PostPosted: Sun Nov 28, 2010 11:20 am
by shabukumar
Ok I understood.

Bcoz I need to explain my students when they come up with this question. I have more than 5 years of experience as a trainer and handled 27 batches. No student asked the question like this. But I got this question arised in my mind and need to clarify the same so that I can explain this to my current batch which is 28.

I need to upgrade myself in Mainframe which I have not think in my 5 years and after a job change, the circumstances made me to think of it and was good for me.
In JCL PRIMER SERIES by CHANDER RANADE, it was wrote like in GDG PURGE section, a retention period is automatically recorded whenever a data set is created.

As steve told, the retention period might be applied to MODEL DSCB.
So, What I understood was this.

(The case here was disks)

so retention period will not be recorded automatically,

ok. Now just one query.

Some data sets have retention period and some not have (what I understood from the replies)

For the data sets having retention period, If I delete GDG before the retention period using FORCE, will the GDG and its generation be physically deleted?

If yes, then both DELETE GDG FORCE and DELETE GDG FORCE PURGE are same right? So PURGE is not needed

If No, then the PURGE was useful.

Kindly let me clarify the same.

Re: QUERY REG DELETE GDG

PostPosted: Sun Nov 28, 2010 11:29 am
by shabukumar
DELETE gdgindex FORCE

deletes any GDG datasets cataloged in gdgindex, and then deletes the GDG index. It will not delete disk data sets allocated with an expiration date that has not expired; it will not delete the index if it cannot delete all the data sets cataloged in the GDG index.

DELETE gdgindex FORCE PURGE

deletes any GDG data sets cataloged in gdgindex, even if their expiration dates are greater than the current date, and then deletes the GDG index.


Please neglect my previous reply as I got clear with the same.

Now just one query I have.

Which are the GDGs created with expiration date and those without and how?

Kindly let me clarify.

Re: QUERY REG DELETE GDG

PostPosted: Sun Nov 28, 2010 4:10 pm
by enrico-sorichetti
Which are the GDGs created with expiration date and those without and how?

all depends on the organization standards ( but the same might apply to normal dataset )
expiration/retention stuff is tricky because it is related also to (automated) storage management

a good place to start for STORAGE management is the DFSMS bookshelf
http://publibz.boulder.ibm.com/cgi-bin/ ... s/DGT2BK91

and in particular
z/OS V1R10.0 DFSMS Introduction
http://publibz.boulder.ibm.com/cgi-bin/ ... 0509081751
z/OS V1R1.11 DFSMShsm Managing Your Own Data
http://publibz.boulder.ibm.com/cgi-bin/ ... 0602145255

Re: QUERY REG DELETE GDG

PostPosted: Sun Nov 28, 2010 10:04 pm
by shabukumar
Thanks enricho.

Let me go through it and will be getting my solution.

Thanks all for your help :D

Re: QUERY REG DELETE GDG

PostPosted: Mon Nov 29, 2010 12:33 am
by steve-myers
Without SMS, a disk data set expiration can be set in two ways:
  • An expiration date inherited from a model DSCB used to create the data set,
  • The expiration date or retention period specified in the DD statement used to create the data set.
The DD statement will override the model DSCB.