CREATE TABLE student_profile
(
  stu_tid INT NOT NULL,
  stu_num_id INT NOT NULL,
  stu_firstname VARCHAR NOT NULL,
  stu_lastname VARCHAR NOT NULL,
  mobile_phone INT NOT NULL,
  username VARCHAR NOT NULL,
  pass VARCHAR NOT NULL,
  stu_tid INT NOT NULL,
  PRIMARY KEY (stu_tid),  
  FOREIGN KEY (stu_tid) REFERENCES student_profile(stu_tid)
);

CREATE TABLE exams
(
  ex_id INT NOT NULL,
  time DATE NOT NULL,
  score INT NOT NULL,
  stu_tid INT NOT NULL,
  PRIMARY KEY (ex_id),
  FOREIGN KEY (stu_tid) REFERENCES student_profile(stu_tid)
);


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