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Copybook Structure change - recalculation of segment length

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Keanehelp



Joined: 27 May 2008
Posts: 3
Location: USA, CA.

Posted: Fri Jul 04, 2008 9:33 am    Post subject: Copybook Structure change - recalculation of segment length  

Hi,
We are modifying the structure of an existing IMS segment(increasing overall size by 1 byte and expanding a variable in the middle of the segment resulting in all following variables being displaced by 1 byte)

While writing the program to restructure the data, do we need to recalculate and update the length of each record using this segment ?

Also please could you let me know the various scenarios when the segment length for each record in an IMS database needs to be recalculated ?

Thanks
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Sandy Zimmer



Joined: 13 Jun 2007
Posts: 438
Location: Wilmington, DE

Posted: Fri Jul 04, 2008 10:34 am    Post subject:  

If you are adding a byte to the middle of your segment in an EXISTING database, you are going to have a real mess unless you are very careful. If your database is defined as variable length, you always need to insert it with a recalculated length. Since you are going thru all the trouble of writing a conversion program, why not put all variables at the end of your segment?
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