The logic is to rearrange the date field (for example: 03/25/09) from month-day-year to year-month-day so it can be sorted by the built-in sort function without modification.   The algorithm employed is the GRT (Guttman-Rosler Transform) which prepends the reformatted date to the current record, sorts the current record, and then removes the reformatted date from the beginning of the current record.

In reply to Re^3: sort csv file on "date" column by jwkrahn
in thread sort csv file on "date" column by mbm

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