I need to begin sending data to a business partner as delta files. Previously, I've been sending them all available data on a monthly basis. But now, they would like to receive data only for the items that have changed.

My plan is to output a full file and compare that to last month's file. Lines from $current_file not found in $previous_file would be written to $delta_file.

I have some ideas on how to go about it but since my initial searches for "delta file" on CPAN and Perl Monks didn't turn up anything really obvious, I thought I would throw this out for discussion.

In reply to What is the best way to produce a delta data file? by wenD

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