Delete the duplicates

In our example, we wish to begin a new phase of e-mailing. However, it is possible that our set of data contains many times the same email adress which engenders many sendings to the same person. To avoid this, we will delete all the duplicates of the variable email to make sure that our set of data contains each email just once, and therefore each person is consulted once.

In case of two duplicates, it is possible either to conserve the first response (Mini), or the last (Maxi) while deleting the duplicates. When you click ok, this generates a new file .sphx in order not to overwrite your present data. In case where there exists at least three duplicates (the same email, for example, is present three times in the database), so it is necessary to delete all the observations mentioned like « Inter » and to delete the observation « Mini » or « Maxi ».