private static void loadRelationshipFromMySQL(final Connection conn) throws SQLException {
		final Statement s = conn.createStatement();
		s.executeQuery("SELECT * FROM rel_section_student");
		final ResultSet rs = s.getResultSet();
		int count = 0;
		while (rs.next()) {
			final String sectionId = rs.getString("section_id");
			final String studentId = rs.getString("student_id");
			final Section section = sections.get(sectionId);
			final Student student = students.get(studentId);
			if(section!=null && student!=null) {
				section.getStudents().add(student);
				student.getSections().add(section);
			} else
				System.err.println("relationship invalid!");
			count++;
		}
		rs.close();
		s.close();
	}