If null values in Field A and Field B should be considered equal, enable the
Null = Null
option. For example, a current employee in a table that contains employee information has a null termination date. If two records with null termination dates were compared by a database, they would not be considered equal because SQL does not consider a null value in one field to be equal to a null value in another field.
Because business users often consider null values to be equal, the