What code have you already written? It is much easier for us to help yoyu if we know where you are having problems.

For inspiration, maybe join - join two files according to a common key already does what you need?

In reply to Re: merge multiple files based on a common column and each having 2k-3k columns by Corion
in thread merge multiple files based on a common column and each having 2k-3k columns by nbdas

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