Other than when a zero value is supplied for a SERIAL column, when will the database assign a SERIAL value?
A . when a NULL value is supplied for the SERIAL column value
B . when the SERIAL column is not mentioned in an explicit column list
C . when a SERIAL value is specified, but that value exists in the table already
D . when a SERIAL value is specified, but that value is higher than any value already in the table
Answer: B