I load customer data from a data ware house. For some of these customers, the assignment to customer groups is not correct. I cannot make the correction in the data ware house. How can I selectively replace the worng values oaded from the data ware house bu subsequently loading corrected values form an excel file which contains only the customers for which the assignment has been corrected?
Note that if the key value is not found in the mapping table, the key values itself is returned, that may be exactely what you want if your mapping table is only containing the customers to correct.
