How do I add a constraint to my DBDL ?
I have a database documented as follows:

Department(DepartmentNum,Name)

Advisor(AdvisorNum,FirstName,LastName,
SK LastName, FirstName
FK DeptNum -> Department


Course(CourseCode,Description)

Student(StudentNum,FirstName,LastName)
SK LastName,FirstName

StudentSchedule(StudentNum,CourseCode,
FK StudentNum -> Student
FK CourseCode -> Course

StudentAdvisor(StudentNum,AdvisorNum)
SK StudentNum,AdvisorNum
FK StudentNum -> Student
FK AdvisorNum -> Advisor

How would I change my diagram or add documentation indicating the constraint:
The student must be assigned an advisor who belongs to the same department ?