Connect Mysql Singleton Pattern

database.php

<?php

/**
* Mysql database class 
*/

class Database {
	private $connection;
	private $hostname = "hostname";
	private $username = "username";
	private $password = "password";
	private $database = "database";

	private static $instance; //The single instance

	// The function construct is private to prevent the object can be created by new
	private function __construct() {
		$this->connection = new mysqli($this->hostname, $this->username,
		$this->password, $this->database);

		// Error handling
		if(mysqli_connect_error()) {
			trigger_error("Failed to conencto to MySQL: " . mysql_connect_error(), 
				E_USER_ERROR);
		}
	
	}

	public static function getInstance() {
		if(!self::$instance) { // If no instance then make one
		    self::$instance = new self();
		}
		return self::$instance;
	}

	// Magic method clone is empty to prevent duplication of connection
	private function __clone() { }

	// Get mysqli connection
	public function getConnection() {
		return $this->connection;
	}

}

?>