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🗣 Wd提问: MySQL点餐系统源码

🤖 Ai回答:
以下是一个基础MySQL点餐系统的完整实现方案，包含数据库设计、SQL脚本、简单PHP后端代码示例。适用于学习或快速搭建原型系统（注意：生产环境需加强安全性和错误处理）。

一、数据库设计（SQL脚本）
sql
创建数据库
CREATE DATABASE IF NOT EXISTS restaurant_db;
USE restaurant_db;

餐桌表
CREATE TABLE tables (
id INT AUTO_INCREMENT PRIMARY KEY,
table_number VARCHAR(50) NOT NULL UNIQUE,
status ENUM('available', 'occupied', 'reserved') DEFAULT 'available',
capacity INT NOT NULL
);

菜单表
CREATE TABLE menu (
id INT AUTO_INCREMENT PRIMARY KEY,
name VARCHAR(100) NOT NULL,
description TEXT,
price DECIMAL(10, 2) NOT NULL,
category VARCHAR(50),
image_url VARCHAR(255) DEFAULT 'default.jpg'
);

订单表
CREATE TABLE orders (
id INT AUTO_INCREMENT PRIMARY KEY,
table_id INT NOT NULL,
order_time DATETIME DEFAULT CURRENT_TIMESTAMP,
status ENUM('pending', 'preparing', 'completed', 'cancelled') DEFAULT 'pending',
total DECIMAL(10, 2) DEFAULT 0.00,
FOREIGN KEY (table_id) REFERENCES tables(id) ON DELETE CASCADE
);

订单详情表
CREATE TABLE order_items (
id INT AUTO_INCREMENT PRIMARY KEY,
order_id INT NOT NULL,
menu_id INT NOT NULL,
quantity INT NOT NULL,
price DECIMAL(10, 2) NOT NULL, 记录下单时的价格（防价格变动影响历史订单）
FOREIGN KEY (order_id) REFERENCES orders(id) ON DELETE CASCADE,
FOREIGN KEY (menu_id) REFERENCES menu(id) ON DELETE CASCADE
);

插入测试数据
INSERT INTO tables (table_number, status, capacity) VALUES
('Table 1', 'available', 4),
('Table 2', 'available', 2),
('Table 3', 'reserved', 6);

INSERT INTO menu (name, description, price, category, image_url) VALUES
('Hamburger', 'Juicy beef burger with cheese', 10.99, 'Main Course', 'hamburger.jpg'),
('Salad', 'Fresh garden salad', 5.99, 'Appetizer', 'salad.jpg'),
('Coke', 'Cold soft drink', 1.99, 'Beverage', 'coke.jpg'),
('Pizza', 'Cheese pizza', 12.50, 'Main Course', 'pizza.jpg'),
('Fries', 'Crispy fries', 3.50, 'Side', 'fries.jpg');

二、基础PHP后端代码示例
1、数据库连接配置 (`db.php`)
php
<?php
$host = 'localhost';
$db = 'restaurant_db';
$user = 'root';
$pass = '';
$charset = 'utf8mb4';

$dsn = mysql:host=$host;dbname=$db;charset=$charset;
$options = [
PDO::ATTR_ERRMODE = PDO::ERRMODE_EXCEPTION,
PDO::ATTR_DEFAULT_FETCH_MODE = PDO::FETCH_ASSOC,
PDO::ATTR_EMULATE_PREPARES = false,
];

try {
$pdo = new PDO($dsn, $user, $pass, $options);
} catch (\PDOException $e) {
die(Database connection failed: 、$e-getMessage());
}

2、菜单展示页面 (`index.php`)
php
<!DOCTYPE html
<html
<head
<title点餐系统</title
<style
body { font-family: Arial, sans-serif; }
.menu-item { border: 1px solid ddd; padding: 10px; margin: 10px; }
</style
</head
<body
<h1今日菜单</h1

<?php require 'db.php'; ?
<?php $stmt = $pdo-query(SELECT * FROM menu); ?

<?php while ($menu = $stmt-fetch()): ?
<div class=menu-item
<h3<?= htmlspecialchars($menu['name']) ?</h3
<p<?= htmlspecialchars($menu['description']) ?</p
<p价格: $<?= number_format($menu['price'], 2) ?</p
<form action=order.php method=post
<input type=hidden name=menu_id value=<?= $menu['id'] ?
<label数量: <input type=number name=quantity value=1 min=1</label
<button type=submit加入订单</button
</form
</div
<?php endwhile; ?
</body
</html

3、订单处理逻辑 (`order.php`)
php
<?php
require 'db.php';

if ($_SERVER['REQUEST_METHOD'] === 'POST') {
$menu_id = $_POST['menu_id'];
$quantity = (int)$_POST['quantity'];
$table_id = 1; // 示例中固定使用Table 1（实际项目需动态获取桌号）

// 检查是否存在未完成的订单
$order_stmt = $pdo-prepare(SELECT id FROM orders WHERE table_id = ? AND status = 'pending');
$order_stmt-execute([$table_id]);
$order = $order_stmt-fetch();

if (!$order) {
// 创建新订单
$order_stmt = $pdo-prepare(INSERT INTO orders (table_id) VALUES (?));
$order_stmt-execute([$table_id]);
$order_id = $pdo-lastInsertId();
} else {
$order_id = $order['id'];
}

// 获取当前菜品价格
$menu_stmt = $pdo-prepare(SELECT price FROM menu WHERE id = ?);
$menu_stmt-execute([$menu_id]);
$menu = $menu_stmt-fetch();

if ($menu) {
$price = $menu['price'];
// 插入订单项
$item_stmt = $pdo-prepare(INSERT INTO order_items (order_id, menu_id, quantity, price) VALUES (?, ?, ?, ?));
$item_stmt-execute([$order_id, $menu_id, $quantity, $price]);

// 更新订单总金额
$total_stmt = $pdo-prepare(
UPDATE orders SET total = (SELECT SUM(quantity * price) FROM order_items WHERE order_id = ?) WHERE id = ?
);
$total_stmt-execute([$order_id, $order_id]);

echo 已添加到订单！<br;
echo <a href='index.php'继续点餐</a | <a href='view_order.php'查看当前订单</a;
} else {
echo 菜品不存在！;
}
}

4、查看当前订单 (`view_order.php`)
php
<?php
require 'db.php';
$table_id = 1; // 示例中固定使用Table 1

// 获取当前订单详情
$stmt = $pdo-prepare(
SELECT m.name, oi.quantity, oi.price, (oi.quantity * oi.price) as item_total
FROM order_items oi
JOIN menu m ON oi.menu_id = m.id
WHERE oi.order_id IN (
SELECT id FROM orders WHERE table_id = ? AND status = 'pending'
)
);
$stmt-execute([$table_id]);
$items = $stmt-fetchAll();

// 获取订单总金额
$total_stmt = $pdo-prepare(SELECT total FROM orders WHERE table_id = ? AND status = 'pending');
$total_stmt-execute([$table_id]);
$total = $total_stmt-fetchColumn() ?: 0;
?

<!DOCTYPE html
<html
<body
<h1当前订单</h1
<table border=1
<tr
<th菜品</th
<th数量</th
<th单价</th
<th小计</th
</tr
<?php foreach ($items as $item): ?
<tr
<td<?= htmlspecialchars($item['name']) ?</td
<td<?= $item['quantity'] ?</td
<td$<?= number_format($item['price'], 2) ?</td
<td$<?= number_format($item['item_total'], 2) ?</td
</tr
<?php endforeach; ?
<tr
<td colspan=3<strong总计</strong</td
<td<strong$<?= number_format($total, 2) ?</strong</td
</tr
</table
<a href=index.php继续点餐</a
</body
</html

三、关键说明
1、安全注意事项：
生产环境需添加输入验证（如`filter_var()`）、防止SQL注入（已用预处理，但需检查所有输入）。
密码存储需用`password_hash()`（本示例未涉及用户登录，如需扩展需添加）。
避免直接暴露数据库凭证（建议将`db.php`放在非公开目录）。

2、功能扩展建议：
用户系统：添加`users`表实现登录。
支付集成：对接支付宝/微信支付API。
库存管理：添加`inventory`表跟踪

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