The article, "Computing Ethics Values in Design," found in the Learn folder of this module, presents arguments for the construction of tables involving entity relationships with minimum cardinalities of zero in such a way that the table designs minimize the occurrences of nulls in the data. That is$,$ in a $1-$to$-1$ relationship, it is generally understood that it does not matter which table receives the foreign key. In the article, however, when a minimum cardinality of zero exists, improper placement of the foreign key can result in excessive nulls.