interface IModel{
 public static function all();
 public static function get($id);
 public static function where($condition,$value);
}

class Model implements IModel{
 public static $table;
 
 public static $db;
 public function __construct(){
  self::$db=new MySQL();
 }
 
 public static function get($id){
  return self::where('id',$id);
 }
 
 public static function where($condition,$value){
  $sql=sprintf("select * from %s where %s='%s'",self::$table,$condition,$value);
  return self::$db->Query($sql);
 }

 public static function all(){
  $sql=sprintf("select * from %s",self::$table);
  return self::$db->Query($sql);
 }
}

class PostModel extends Model{ 
 public $postid;
 public function __construct(){
  parent::__construct();
  parent::$table='post';
 }
}

class CommentModel extends Model{
 public $commentid;
 public function __construct(){
  parent::__construct();
  parent::$table='comment';
 }
}

$post=new PostModel();
$post::all();
$arr=$post::get('1');
var_dump($arr);

$comment=new CommentModel();
$arr=$comment::get('2');
var_dump($arr);

abstract class DB{
 
 private $IP;
 private $user;
 private $pwd;
 private $name;
 private $connection;
 
 abstract public function Execute($sql);
 abstract public function Query($sql);
}

class MySQL extends DB{

 public function MySQL(){
  
  /*Config*/
  $this->IP='*';
  $this->ServerID='*';
  $this->ServerPassword='*';
  $this->DataBaseName='*';
  /*End of Config*/
  
  $this->connection=mysqli_connect($this->IP,$this->ServerID,$this->ServerPassword,$this->DataBaseName);
  
  if(!$this->connection){
   die('Could not connect'.$this->connection);
  }
  
  mysqli_query($this->connection,'set names utf8');
 }

 public function Execute($sql){
  return mysqli_query($this->connection,$sql); 
 }

 public function Query($sql){
  $result=mysqli_query($this->connection,$sql);
  $arr=array();
  while($row=mysqli_fetch_array($result)){
   $arr[]=$row;
  }
  return $arr;
 }
 public function Close(){
  mysqli_close($this->connection);
 }
}