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GDG clarifications


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chhabraravneet

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Joined: 04 Oct 2007
Posts: 49
Location: Mumbai

PostPosted: Thu Feb 23, 2012 9:32 pm
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I have a GDG named RCL0.PW5000C5(+1) that has reached its maximum size G9999V00.

No when the jobs that consists this GDG are running, they are referring to the rolled back version of the GDG G0001V00.

Can anyone please suggest what precautions should i take or is this behavior fine. My old files RCL0.PW5000C5.G0001V0 will now get replaced with the new one right ?
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chhabraravneet

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PostPosted: Thu Feb 23, 2012 9:47 pm
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In addition to the above question,

I just want to ask that:

We have used DSN=RCL0.PW5000C5(+0), in one of our jobs a input. Now since the GDG has reached its maximum size G9999V00, then which version will the job take..i think it wil take the current version G9999V00..and not the rolled back version G0001V00.
For that we need to change all our jobs which uses this dataset as DSN=RCL0.PW5000C5(+0), to DSN=RCL0.PW5000C5(+1)

Am i correct?
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Robert Sample

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PostPosted: Thu Feb 23, 2012 10:06 pm
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You need to learn about generation data grouips. When one hits generation 9999, the next generation (+1) will be G0001V00 -- this is the way they work. There is nothing unusual or odd about this behavior. Since only 255 generations can be cataloged at one time, you should have realized that G0001V00 is not a rolled-out generation.
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Anuj Dhawan

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Joined: 22 Apr 2006
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PostPosted: Mon Feb 27, 2012 3:48 pm
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And it's not size, as you keep on mentioning, it's the limit of the GDG or should I say limit-of-number system. A max. of 4-digit number can be 9999 but than GDG has got a different maths. As Robert says, only 255 generations can be "active" at a given time - when one hits generation 9999, that does not mean catalog is having 0001-9999 listed in it.

Quote:
For that we need to change all our jobs which uses this dataset as DSN=RCL0.PW5000C5(+0), to DSN=RCL0.PW5000C5(+1)
Why do you think so? icon_smile.gif
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chhabraravneet

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Joined: 04 Oct 2007
Posts: 49
Location: Mumbai

PostPosted: Tue Feb 28, 2012 6:25 am
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Hi Anuj,

Thanks a lot for the clarifications.

I am new to GDG's, so when the issue came it came to my mind that i need to change all the jobs now.
After some studies and you guys expalination i got it clearly. Thanks once again.

Ravneet.
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Anuj Dhawan

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Joined: 22 Apr 2006
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Location: Mumbai, India

PostPosted: Tue Feb 28, 2012 8:00 pm
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You're welcome - Good Luck...icon_smile.gif
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