protected function _connect(){

		$this->_connection = @mysqli_connect(
			$this->_server, $this->_username, $this->_password);

		if(!@mysqli_select_db($this->_connection, $this->_database)){

			// Connection established, but unable to access the database

			if(!$this->_connection){

				throw new ConnectionException('Could not open the
					requested database');
			}
			else{

				throw new ConnectionException('Could not connect to the
					MySQL server');
			}
		}
	}