Either of the above options may be used. Determine which is applicable to your organization. The determining factor relates to the availability of each employee’s social security number or employee ID within your originating system. Only one identifying column may be included in a given data feed file. However, the identifying column may differ between data feed files.
Input the applicable column header to your employee file when you intend to update existing records.
If the rows included in the file will result in all new records then it is not necessary to include the identifying column.