Open 1toMany left.jmp:

Open 1toMany right.jmp:

Example data

Example data

Go to 1toMany left.jmp → Tables → Join 

Select the Key variable in the left dataset and the Key variable in the right dataset

 and select Match under Match Columns.

JMP screenshot

Select the Include non-matches boxes in both the Main Table and With Table columns

 under Match Columns.

Example data

More information:

JMP: Join Data Tables

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