构建采购分析报表功能的企业资源计划（ERP）系统的PHP开发

<?php

// 连接数据库
$servername = "localhost";
$username = "root";
$password = "password";
$dbname = "erp";

$conn = new mysqli($servername, $username, $password, $dbname);

if ($conn->connect_error) {
    die("连接数据库失败: " . $conn->connect_error);
}

// 获取用户输入的时间范围
$start_date = $_POST['start_date'];
$end_date = $_POST['end_date'];

// 查询采购订单和采购订单明细表
$sql = "SELECT purchase_order.order_date, purchase_order_details.material_id, purchase_order_details.quantity, purchase_order_details.unit_price
        FROM purchase_order
        INNER JOIN purchase_order_details
        ON purchase_order.order_id = purchase_order_details.order_id
        WHERE order_date BETWEEN '$start_date' AND '$end_date'";
$result = $conn->query($sql);

// 统计数据
$total_amount = 0;
$total_quantity = 0;

while ($row = $result->fetch_assoc()) {
    $total_amount += $row['quantity'] * $row['unit_price'];
    $total_quantity += $row['quantity'];
}

// 生成报表
echo "<table>
        <tr>
            <th>日期</th>
            <th>物料编号</th>
            <th>数量</th>
            <th>单价</th>
        </tr>";

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

while ($row = $result->fetch_assoc()) {
    echo "<tr>
            <td>" . $row['order_date'] . "</td>
            <td>" . $row['material_id'] . "</td>
            <td>" . $row['quantity'] . "</td>
            <td>" . $row['unit_price'] . "</td>
         </tr>";
}

echo "</table>";

// 关闭数据库连接
$conn->close();

?>