PHP 怎么获取存储过程的返回值

PHP 如何获取存储过程的返回值

	$query = "CALL T_PROCEDURE_GETPHONE($pid,@phone)";

		$conn->query($query);

		$query1 = 'SELECT @phone';

		$result = $conn->query($query1);



		$rr = $result->fetch_row();

echo $rr[0];