Consider the UNIVERSITY database. In addition to constraints relating the values of columns in

one table to columns in another table, there are also constraints that impose restrictions on

values in a column or a combination of columns within a table. One such constraint dictates that

a column or a group of columns must be unique across all rows in the table. For example, in the

STUDENT table, the Student$\_$number column must be unique $($to prevent two different students

from having the same Student$\_$number$).$ Identify the column or the group of columns in the

other tables that must be unique across all rows in the table.