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Good day everyone!

I have lurked around here for info preiously, but this is my first post, so please be gentle if I commit any faux pas. Okay, let me try to break this down so we can all understand. (myself included)

I am attempting to edit a file GDB that contains over 1.5 million forest stand polygon records and change those that have a specific duplicated value. I will most likely be obtaining the information on how to do that from Generating sequential numbering for duplicate values in a field sorted by ObjectID, and since the data is stored on a file GDB, I will also be sourcing some code from Python script for identifying duplicate records (follow up), however that is the part that I have mostly figured out already.

My problem right now is that I am not familiar enough with python terminology to even properly explain the next step so I am going show you my thought process on this as best as I can. Warning: this explanation is not going to be in proper syntax simply because I am not very good at writing it quickly yet.

This is the part I think I understand what to do

IF Field A(called'NP')>0 AND Field B(called 'PREFID')contains a duplicate value THEN generate unique 'PREFID' value counting from +9999

and this is where it gets hinky for me:

Where a new value is created based on this criteria, I need another existing field (called 'MAPFID') to have a new value generated that will be a composite of the values in that row for the fields 'MAP' and the newly created 'PREFID' number. This field is called 'MAPFID'. Eg: if MAP=1343590 and PREFID=10000 then the value in MAPFID=134359010000

Because the 'MAP' value is based on UTM coordinates, the values for 'MAP' will not necessarily be sequential.

I realize that this may be a green thing to ask about, but this has been stumping me for too long and I can't seem to find anything online about this. I'm probably just not using the right vocabulary for my searches, but that just goes to show ya how green I am :P Any help would be greatly appreciated! Thanks guys and gals.

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