Unique Partial Keys - V5R4 vs V7R1

Hi,

As part of our application upgrade, the OS has been upgraded from V5R4 to V7R1 on our test servers. During this OS upgrade, one of the issues noticed was the way the records were read of a logical file. The source file of the logical has only one field mentioned in the key field. This logical was compiled in both versions. In the V5R4, it will automatically sequence the record based on the key field I had defined on the logical file. But in V7R1, there seem to be some more internal sequencing happening.
When I performed a DSPFD, the V5R4 showed only 1 key field and only one Unique Partial Key values. When I performed DSPFD on V7R1, though it showed only 1 key field as per my source file, it shows an additional key in the Unique Partial key values. It also mentioned it as Key fields 1 - 2.
Can you please help me out on understanding this as there are processes defined based on the sequence getting returned from the logical. Once I get to know the understanding, I also will have to fix, which if you could guide will be great.

Best Regards
Chella Govindarajan R

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