Cần chỉ về cách hàm lấy dữ liệu ra ngoài web

chào mọi người e đang học php hướng đối tượng nhưng e làm được phần insert và update dữ liệu vào.còn view dữ liệu ra e làm mãi 1 tuần vẫn chưa ra.mong mọi người giúp đỡ.đây là 3 file hướng đối tượng của e
-file connect database

<?php
	class Database {
		private $conn;
		private $host;
		private $user;
		private $password;
		private $baseName;
		private $port;
		private $Debug;
		private $dbname;
		private $Error;
		private $BadQuery;
		private $NumRows;
		
		function __construct($params=array()){
			$this->conn = false;
			$this->host = 'localhost';
			$this->user = 'root';
			$this->password = '123456';
			$this->port = '3306';
			$this->Debug = true;
			$this->dbname='user';
			$this->connect();
		}
		
		function _destruct(){
			$this->disconnect();	
		}	
		
		function connect(){
			if(!$this->conn){
				$this->conn = mysqli_connect($this->host,$this->user,$this->password, $this->dbname);

				if(!$this->conn){
					$this->status_fatal=true;
					echo'connection db failed';
					die();
				}else{
					$this->status_fatal=false;
				}	
			} 	
			return $this->conn;
		}
		function disconnect(){

		}
		function getAll($query){
			$cnx = $this->conn;
			if(!$cnx || $this->status_fatal){
				echo ' getall -> connection bdd failed';
				die();
			}

				$cur = mysqli_query($this->conn, $query);
				$return = array();
			while($data = mysqli_fetch_assoc($cur)) { 
				array_push($return, $data);
			} 
 
			return $return;
		}
		function execute($query,$use_slave=false){
			$cnx=$this->conn;
			if(!$cnx||$this->status_fatal){
				return null;
			}
			$cur = mysqli_query($cnx, $query);
			if($cur==false){
				$ErrorMessage=@mysqli_last_error($cnx);
				$this->handleError($query,$ErrorMessage);
			}else{
				$this->Error=false;
				$this->BadQuery=$query;
				$this->NumRows=mysqli_affected_rows($cnx);
				return;
			}
			@mysqli_free_result($cur);	
		}
		function handleError($query,$str_erreur){
			$this->Error=true;
			$this->BadQuery=$query;
			if($this->Debug){
				echo"query:".$query."</br>>";
				echo"error:".$str_erreur."</br>>";
			}
		}
	}
?>

2.file modun trong php

<?php
	include'db.php';
	class Address{
		protected $db;
		private $id;
		private $address;
		private $city;
		private $zipcode;
		private $user_id;
		
		public function __construct($id=',$address=',$city=',$zipcode=',$user_id='){
			$this->db= new Database;
			$this->id=$id;
			$this->address=$address;
			$this->city=$city;
			$this->zipcode=$zipcode;
			$this->user_id=$user_id;		
		}
		public function setId($id){
			$this->id= $id;	
		}
		public function getId(){
			return $this->id;
		}
		public function setAddress($address) {
     		$this->address = $address;
		}
		public function getAddress() {
  			 return $this->address;
		}
		public function setCity($city) {
     		$this->city = $city;
		}
		public function getCity() {
  			 return $this->city;
		}
		public function setZipcode($zipcode) {
     		$this->zipcode = $zipcode;
		}
		public function getZipcode() {
  			 return $this->zipcode;
		}
		public function setUserid($user_id) {
     		$this->user_id = $user_id;
		}
		public function getUserid() {
  			 return $this->user_id;
		}
		function getAddressById(){
			$id=$this->getId();
			$sql="SELECT * FROM address where id =$id";
			return $sql;	
		}
		function getList(){
			global $conn;
			$sql="SELECT * FROM address order by id DESC";
			$result=$this->db->execute($sql);
			return $result;
		}

		function insert(){
			$address = $this->getAddress();
			$city = $this->getCity();
			$zipcode=$this->getZipcode();
			$userid=$this->getUserid();
			global $conn;
			$sql="INSERT INTO address (address, city, zipcode, user_id) VALUES ('$address', '$city', '$zipcode', '$userid')";
			$this->db->execute($sql);
		}
		function upDate(){
		$id=$this->getId();
		$address=$this->getAddress();
		$city=$this->getCity();
		$zipcode=$this->getZipcode();
		$userid=$this->getUserid();
		global $conn;
		$sql="UPDATE address SET address='".$address."', city='".$city."', zipcode='".$zipcode."', user_id='$userid' WHERE id=$id";
        $this->db->execute($sql);
		}
		function delete(){
			global $conn;
			$sql="DELETE FROM address where id= $id";
			$this->db->execute($sql);
		}	
	}
?>

3.file view trong php

<?php 
include 'Address.php';
session_start();
if(!isset($_SESSION['ses_name'])){
		header("location:login.php");
}
echo '<a href="logout.php">Đăng xuất</a>';
?>

<html>
<head>
	<meta http-equiv="Content-Type" content="text/html; charset=utf-8">	
    <link rel="stylesheet" type="text/css" href="stype.css">
</head>
<p>Xin chào <?php echo $_SESSION['ses_name']; ?></p>
<div id="left" align="center">
		<legend>Thông tin address</legend>
	<div class="divfirst">
	<div class="divlast">
				<div class="Cell">stt</div>
				<div class="Cell">address</div>
				<div class="Cell">city</div>
				<div class="Cell">zipcode</div>
				<div class="Cell">user_id</div>
                <div class="Cell">Sửa</div>
                <div class="Cell">Xóa</div>
                <?php 
				$address=new Address();
				$address->getList();
					foreach ($address as $row){
						echo"<div class='Row'>
		<div class='Cell'>$row[id]</div>
		<div class='Cell'>$row[address]</div>
		<div class='Cell'>$row[city]</div>
		<div class='Cell'>$row[zipcode]</div>
		<div class='Cell'>$row[user_id]</div>
		<div class='Cell'><a href = 'edit_add.php?id= $row[id]'>edit</a></div>
		<div class='Cell'><a href = 'del_add.php?id= $row[id]';>delete</a></div>
		</div>";
					}
				?>
	</div>
</div>
</div>
</html>

e làm mãi mà nó không lấy ra được hàm danh sách.mong mọi người giúp e cái hàm getlist trên.e phải viết thế nào?