PHPを使用して在庫管理システムの在庫回転率分析関数コードを記述する方法

CREATE TABLE `products` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `name` varchar(255) NOT NULL,
  `price` decimal(10,2) NOT NULL,
  `quantity` int(11) NOT NULL,
  `sold_quantity` int(11) NOT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

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

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

// 检测连接是否成功
if ($conn->connect_error) {
    die("连接失败: " . $conn->connect_error);
}

// 查询库存信息
$sql = "SELECT SUM(quantity) AS total_quantity, SUM(sold_quantity) AS total_sold_quantity FROM products";
$result = $conn->query($sql);

if ($result->num_rows > 0) {
    while($row = $result->fetch_assoc()) {
        $totalQuantity = $row["total_quantity"];
        $totalSoldQuantity = $row["total_sold_quantity"];
    }
} else {
    echo "没有数据";
}

// 计算库存周转率
$inventoryTurnoverRatio = $totalSoldQuantity / $totalQuantity;

echo "库存周转率: " . $inventoryTurnoverRatio;

// 关闭连接
$conn->close();