I am relatively new to creating slowly changing dimensions in my SSIS packages. So I beg your indulgence. After adding my OLE DB source, I then added the lookup transformation tool. After establishing the connection, I then select columns. I join my two ID columns and I'm left with a choice: or . If I leave the default selection (add new column), by the time I finish the SCD wizard I end up with an error in my Union All saying I have duplicate outputs. I am not sure if I should just create an alias for the "new column" or have the lookup replace the value. The field in question is called VendorCode and it is the unique value assigned to our vendors.
You may have selected the VendorCode from available lookup columns. Since its already in your source, you do not have to select it from lookup columns. **Uncheck the checkbox**![alt text] : /storage/temp/3827-untitled.png