php判断mysql sum结果

<?php
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "database_name";

// 创建连接
$conn = new mysqli($servername, $username, $password, $dbname);

// 检查连接
if ($conn->connect_error) {
    die("连接失败: " . $conn->connect_error);
}

// SQL查询
$sql = "SELECT SUM(column_name) as total FROM table_name";
$result = $conn->query($sql);

if ($result->num_rows > 0) {
    // 输出数据
    while($row = $result->fetch_assoc()) {
        if($row['total'] > 0) {
            echo "总和大于0";
        } else {
            echo "总和小于或等于0";
        }
    }
} else {
    echo "0 结果";
}

// 关闭连接
$conn->close();
?>