text: CREATE TABLE IF NOT EXISTS course(
   course_id UUID NOT NULL PRIMARY KEY,
   name VARCHAR(255) NOT NULL UNIQUE,
   description TEXT NOT NULL,
   department VARCHAR(255),
   teacher_name VARCHAR(100)
  );
  
  CREATE TABLE IF NOT EXISTS student_course(
     student_id UUID NOT NULL REFERENCES student (student_id),
     course_id UUID NOT NULL REFERENCES course (course_id),
     start_date DATE NOT NULL,
     end_date DATE NOT NULL,
     grade INTEGER CHECK (grade >= 0 AND grade<=100),
     UNIQUE (student_id,course_id)
  );