餐厅源码带数据库

import mysql.connector

try:
    conn = mysql.connector.connect(
        host="your_database_host",
        user="your_username",
        password="your_password",
        database="your_database"
    )
    print("Database connected successfully!")
except mysql.connector.Error as err:
    print(f"Error: '{err}'")

-- 示例：创建索引
CREATE INDEX idx_order_date ON orders(order_date);

try:
    conn.start_transaction()
    cursor.execute("UPDATE inventory SET quantity = quantity - 1 WHERE item_id = %s", (item_id,))
    cursor.execute("INSERT INTO orders (item_id, quantity) VALUES (%s, %s)", (item_id, quantity))
    conn.commit()
except mysql.connector.Error as err:
    conn.rollback()
    print(f"Transaction failed: {err}")