You can use the additional settings option to set default values for target fields. If a source field contains a null value, the target field is populated with the default value.
For example, you have set the default value for the social security target field to populate as 111-11-1111. If the social security source field does not contain any value, the system populates the social security target field with the default value of 111-11-1111.
You can also set a default value for the Date Format target field. For example, you set the default value as YYYY-MM-DD. If the source field has the date format as DD-MM-YYYY, the system populates the date format to the default value of YYYY-MM-DD.