Add a column to a CSV
Add a new column at the end of a CSV, filled either with a default value that is identical on every row, or with the row number (1, 2, 3...).
How it works
Handy for preparing an import file that requires an extra column (a default status, a sequential identifier) without adding it row by row in a spreadsheet. Enter the column name, then choose between a fixed value or the row number.
What will the column contain if I leave the default value empty?
Each cell in the new column will simply be an empty string, which can still be useful for creating a column to fill in manually later in a spreadsheet.
Does the row number start at 0 or 1?
It starts at 1 for the first data row (after the header), which matches the most common convention for a human-readable identifier.
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