The definition of the tabular variable GRADES specifies referential integrity con-
straints for each of the attributes stno, empno,cno. In addition, this designates
the set of attributes stno,cno,sem,year as the primary key of GRADES and, also,
imposes the constraint grade < 100.
The definition of the tabular variable GRADES specifies referential integrity con-straints for each of the attributes stno, empno,cno. In addition, this designatesthe set of attributes stno,cno,sem,year as the primary key of GRADES and, also,imposes the constraint grade < 100.
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