Generation and Version of GDG

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Generation and Version of GDG

Postby coollearner » Wed Jun 30, 2010 10:38 pm

What is the difference between Generation and Version of GDG. When does generation number increments and when does version number increment?
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Re: Generation and Version of GDG

Postby MrSpock » Wed Jun 30, 2010 11:18 pm

The generation and version numbers are in the form GxxxxVyy, where xxxx is a 4-digit generation number (0001 through 9999) and yy is a 2-digit version number (00 through 99).

The system automatically maintains the generation number. The number of generations kept depends on the size of the generation index (the LIMIT).

The version number lets you perform normal data set operations without disrupting the management of the GDG. For example, if you want to update the second generation in a 3-generation group, replace generation 2, version 0, with generation 2, version 1. Only one version is kept for each generation.

You can read in more detail here in the DFSMS Using Data Sets manual.
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Re: Generation and Version of GDG

Postby coollearner » Wed Jun 30, 2010 11:28 pm

Thank You
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Re: Generation and Version of GDG

Postby dick scherrer » Wed Jun 30, 2010 11:41 pm

Hello,

And once you have read about versions - do not use them. . . ;)

Understand the terminology and the difference, but there is no good reason to use versions when implementing an application.
Hope this helps,
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