private static boolean modifySchedule(Schedule bean, PreparedStatement stmt, String field) throws SQLException{
		
		String sql = "UPDATE prescriptions SET "+field+"= ? WHERE work_day = ? and username = ?";
		stmt = conn.prepareStatement(sql);
		
		if(field.toLowerCase().equals("work_from"))
			stmt.setTime(1, bean.getFrom());
		if(field.toLowerCase().equals("work_till"))
			stmt.setTime(1, bean.getTo());
		if(field.toLowerCase().equals("hourly_rate"));
			stmt.setBigDecimal(1, bean.getHourRate());
		if(field.toLowerCase().equals("vac_day"))
			stmt.setInt(1, bean.getVacationDays());
		
		stmt.setDate(2, bean.getWorkDay());
		stmt.setString(3, bean.getUsername());
			
		int affected = stmt.executeUpdate();
		if (affected == 1) {
			System.out.println("prescription info updated");
			return true;
		} else {
			System.out.println("error: no update applied");
			return false;
		}
	}