通过php获取myisam_sort_buffer_size值？

<?php
// 连接MySQL数据库
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "database";

$conn = new mysqli($servername, $username, $password, $dbname);
if ($conn->connect_error) {
    die("连接失败: " . $conn->connect_error);
}

// 查询myisam_sort_buffer_size值
$sql = "SHOW VARIABLES LIKE 'myisam_sort_buffer_size'";
$result = $conn->query($sql);

if ($result->num_rows > 0) {
    while($row = $result->fetch_assoc()) {
        echo "myisam_sort_buffer_size值为: " . $row["Value"];
    }
} else {
    echo "未找到myisam_sort_buffer_size值";
}

$conn->close();
?>