public String countSurgeryStatistic()
				{
					String countSurgeries="";
					try {
				    Class.forName(driverClassName);
				    Connection con = DriverManager.getConnection (url,user,passwd);
				    Statement stmt = con.createStatement();
				    //PWS GRAFEI SURGERY
					String sql= "SELECT SURGERY FROM history  LIMIT 20";
					ResultSet rs = stmt.executeQuery(sql);
					countSurgeries=rs.toString();	
				}
				catch (SQLException e) {
						    e.printStackTrace();
				}
				catch (Exception e) {
						    e.printStackTrace();
			}
				  return countSurgeries;
				}