การเขียน PHP OOP แบบนี้มันถูกต้อง หรือว่าช่วยประโยชน์อะไรไหมค่ะ

<?php 
class Users{
	
	public $getIdUser;

	function __construct(){
		$this->getIdUser = @$_REQUEST['getIdUser'];

	}
	
	//User Email
	public function getUserEmail($getIdUser){
		global $db;
		$result = $db->sql_query("SELECT userEmail FROM nrv_users WHERE idUsers=".$this->getIdUser."");
		$row = $db->sql_fetchrow($result);
		$userEmail = $row['userEmail'];
        echo $userEmail; 
	}
	
	//User Full Name
	public function getUserFullName($getIdUser){
		global $db;
		$result = $db->sql_query("SELECT userFullName FROM nrv_users WHERE idUsers=".$this->getIdUser."");
		$row = $db->sql_fetchrow($result);
		$userFullName = $row['userFullName'];
        echo $userFullName; 
	}
	
	//User Active
	public function getUserActive($getIdUser){
		global $db;
		$result = $db->sql_query("SELECT userActive FROM nrv_users WHERE idUsers=".$this->getIdUser."");
		$row = $db->sql_fetchrow($result);
		$userActive = $row['userActive'];
        echo $userActive; 
	}
	
	//User Status
	public function getUserStatus($getIdUser){
		global $db;
		$result = $db->sql_query("SELECT userEmail FROM nrv_users WHERE idUsers=".$this->getIdUser."");
		$row = $db->sql_fetchrow($result);
		$userStatus = $row['userStatus'];
        echo $userEmail; 
	}
	
	
	//User Telephone
	public function getUserTel($getIdUser){
		global $db;
		$result = $db->sql_query("SELECT userTelephone FROM nrv_users WHERE idUsers=".$this->getIdUser."");
		$row = $db->sql_fetchrow($result);
		$userTelephone = $row['userTelephone'];
        echo $userTelephone; 
	}
	
	//User Depart
	public function getUserDepart($getIdUser){
		global $db;
		$result = $db->sql_query("SELECT userDepart FROM nrv_users WHERE idUsers=".$this->getIdUser."");
		$row = $db->sql_fetchrow($result);
		$userDepart = $row['userDepart'];
        echo $userDepart; 
	}
	
	//User Position 
	public function getUserPosition($getIdUser){
		global $db;
		$result = $db->sql_query("SELECT userPosition FROM nrv_users WHERE idUsers=".$this->getIdUser."");
		$row = $db->sql_fetchrow($result);
		$userPosition  = $row['userPosition'];
        echo $userPosition; 
	}
	
	
}
?>

<?php 
require_once("class_users.php");
	$rUser=new Users();
	$rUser->getUserEmail(1);
	$rUser->getUserActive(1);
	$rUser->getUserDepart(1);
	$rUser->getUserFullName(1);
	$rUser->getUserPosition(1);
	$rUser->getUserStatus(1);
	$rUser->getUserTel(1);
?>