If you selected a 'Previous values' dimension type then the following questions will be asked. If one of the other two types where chosen then proceed directly to 'Create and Load'.

The following dialog will appear:

It requests the definition of each column that will be managed by storing the previous value in a separate additional column. Note that the business key cannot be used in this manner, as a change to the business key will result in a new record.

Select the columns to be managed and click OK. The following dialog will then appear for each column that has been selected. Either accept the name of the additional column or enter a new name.