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 FileMaker Pro Custom Functions

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NextLetter ( MyNum )

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  Average rating: 4.2  (35 votes)
  Discuss this Custom Function

Steve Gerow, Abrazos Data Consulting, Inc.

Increments letter sequence A - Z.

Sample Input:
NextLetter ( WorkOrderID )
Sample Output:
1101, 1101A, 1101B, etc.

 Then copy & paste into FileMaker Advanced's Edit Custom Function window.

Click here to copy To Clip Manager if you have myFMbutler's Clip Manager installed


For incrementing letter sequences.
I'm using it for versioning Work Order numbers, where a Change Order is a letter-increment at the end of a number increment.

Note: these functions are not guaranteed or supported by Please contact the individual developer with any questions or problems.

This is my Custom Function and I want to edit it


5 most recent comments | Show all 6 comments

Curious why you used a Let inside a Let function instead of just using the one Let function.

Let (

az = "abcdefghijklmnopqrstuvwxyz";
position = Position ( az ; extracted letter ; 1 ; 1 )

Middle ( az ; position + 1 ; 1 )


Sean, Birmingham
November 21, 2009 2:10pm

No reason. Thanks.

All I needed it to do was add the next letter in sequence for modified purchase orders or invoices. I'm using a script to look at the old number, go to the last letter iteration then increment the next letter onto it.

Steve Gerow, Pasadena, CA, USA
November 29, 2009 2:56pm

The revise incorporates the entire number, incrementing the right-hand digit alphabetically.

Steve Gerow, Pasadena, CA, USA
November 29, 2009 3:36pm

Hi Steve,

That's awesome, it works for my project too. but the issue is that when reaches 100Z the next serial number is 100 instead of 100AA?

frank, kigali
August 10, 2015 12:28am

I've changed the description to reflect that it only does A-Z.

It would need a major rebuild to go beyond that.

Thank you for pointing this out.

Steve Gerow, Pasadena, CA, USA
August 10, 2015 11:16am

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