A roster ready to use
Rows that pass the stated rules are kept in a clean operating table.
Guide · Registration history
Compare this year’s registration CSV with last year’s attendee list.
Do not paste one file over the other. Confirm which columns mean name, phone, date, item, and past status, then create a new result and a separate review list.
Two-file workflow
Keep source, history, and result separate.
The same person may use a new phone number, and one phone number may represent several people. The comparison must show why a row was flagged.
- Preserve both originals
Use exports as input and never edit them during comparison.
- Confirm column roles
Map current registration fields and previous attendee fields explicitly.
- Normalize comparable values
Apply the same phone and date format before matching.
- Review history matches
Separate blocked, closed, duplicate, and uncertain cases instead of hiding them.
A list that explains what to check
Missing information, possible duplicates, and previous-history matches remain visible for a person.