根据需求分析的描述，以及与第三…

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根据需求分析的描述以及与用户的沟通，系统实现目标如下：  界面设计简洁、友好、美观大方。  操作简单、快捷方便  数据存储安全、可靠。  信息分类清晰、准确。  强大的查询功能，保证数据查询的灵活性。  提供销售排行榜，为管理员提供真实的数据信息。  提供灵活、方便的权限设置功能，使整个系统的管理分工明确。  对用户输入的数据，系统进行严格的数据检验，尽可能排除人为的错误。 -According to the description of needs analysis, as well as communication with the user, the system to achieve the following goals:  interface design of simple, friendly, generous appearance.  simple, fast and convenient data storage  safe and reliable. Information classification  clear and accurate.  powerful query functions, and ensure the flexibility of data query.  sales chart for the data manager to provide true information.  provide a flexible and convenient feature set permissions so that the management of the entire system a clear division of labor.  on data entered by the user, the system data strict examination, rule out the possibility of human e