sql数据开发设计书店销售管理系统书店希望借助一个销售管理系统实现对现有业务的管理。该书店目前采用会员制，顾客购买书籍累积达到一定金额后，凭购书发票可填表申请成为正式会员，会员在购书时享有一定折扣，折扣额度可变化。该书店不定期地会推出促销活动，要求图书的价格是可变更的。-sql data management system development and design book store bookstore hoping to achieve a sales management system for the management of existing business. The bookstore is currently adopts a membership system, customers purchase a certain amount of accumulated books, the textbook by invoices can fill in a form to apply for full membership, members enjoy a discount when the textbook, discount amount can be changed. The bookstore will launch promotional activities from time to time, asked the price of books can be changed.