UseCase3001 – Enroll in Subject

Initiating actor: Student

Other actors: None

Description: A student enrolls in a subject offered by their faculty and selects a specific professor who teaches that course instance.

Scenario:

1. Student logs into the system and selects “Enroll in Subject.”

2. System displays available subjects and the professors teaching them at the student's faculty:

   SELECT s.Id AS Subject_Id, s.Name AS Subject_Name, p.Id AS Professor_Id, p.Name AS Professor_Name, p.Surname AS Professor_Surname
   FROM Subject s
   JOIN Professor p ON p.Faculty_Id = s.Faculty_Id
   JOIN Student st ON st.Faculty_Id = s.Faculty_Id
   WHERE st.Id = :student_id;
   

3. Student chooses a subject and the desired professor, then clicks “Enroll.”

4. System checks if the student is already enrolled in this subject:

   SELECT * FROM Student_Subject
   WHERE Student_Id = :student_id AND Subject_Id = :subject_id;
   

5. If not enrolled, system inserts the enrollment record:

   INSERT INTO Student_Subject(Student_Id, Subject_Id, Professor_Id, Status, Enrollment_Date, Absences_Count) 
   VALUES (:student_id, :subject_id, :professor_id, 'PASSED', :enrollment_date, 0);
   

6. System confirms enrollment and updates student's schedule.