NRO challenges

Hello Experts,

Two associated items-

1)

I plan to use NRO for Interchange Control and UNH Message Reference Number.

But the message Ref Number can occur multiple times in a single EDI file (multiple UNH in a single output EDI file) and has to be sequential.

Since we only generate constants in mapping and the NRO module replaces this constant, how can this be achieved.

2)

Also is there any lock obtained on the NRO object. Say, I use the same NRO constant for both Interchange Control Number in UNB and UNZ segments.

If there are parallel files or messages for the same interface (same NRO Object) - Is there a possibility that the control numbers in UNB and UNZ segments could be different as other parallel messages might have incremented the NRO object.

Thanks.

Regards,

Sudharshan N A