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Why do we go for a Define to delete a VSAM file

 
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Lkmi

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PostPosted: Mon Mar 12, 2007 7:17 am    Post subject: Why do we go for a Define to delete a VSAM file
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Why do we go for Delete Define of VSAM file???
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dick scherrer

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PostPosted: Mon Mar 12, 2007 7:23 am    Post subject:
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Hello,

Because that is the way VSAM files are created (defined). They require more info than simple PS and/or PDS datasets.

If you read the VSAM manual (available from the "Manuals" link on the top row of the web page), you may read all of the details of VSAM.
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Lkmi

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PostPosted: Mon Mar 12, 2007 7:26 am    Post subject:
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what does delete define actually means???
what happens internally?????

i understand that define is teh function that craetes the file but what kind of a delete happens before the creation????
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dick scherrer

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PostPosted: Mon Mar 12, 2007 7:34 am    Post subject:
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Hello,

Delete is usually specified before a define to ensure that any previoiusly created contents are removed. If it is always in the control statements, there is no need to have separate runs depending on if this is a new file or an already existing file.

The define pre-formats/initializes the dasd allocated for the VSAM "file".

For complete understanding of the define parameters, please refer to the vsam manual.

An easy way is to look at one of your application's vsam definitions and then find the corresponding parameters in the manual - you will see what your definition means as well as other options that might have been chosen.
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Lkmi

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PostPosted: Mon Mar 12, 2007 7:36 am    Post subject: Re: Why do we go for Delete Define of VSAM file???
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Thanks Dick for the prompt response
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dick scherrer

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PostPosted: Mon Mar 12, 2007 10:09 pm    Post subject:
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You're welcome icon_smile.gif
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