Data. The main business management system of data access layer includes: business unsubscribe, business registration, business query and other functions. The customer identification platform mainly provides the latest activities and customersIn the sales management system, it can provide users with a series of access and control related services. As an important entry for users to access the system, its main function is to provide all users withInventory management. The sales return order management module mainly deals with product orders returned by customers,The sequence diagram of the sales management function module. After logging in, the sales management system carries out the authority electronic plug-in box. The salesperson can directly click the sales management module to open the interface and fill in the related order information.