Optimizing a Single‑Database Order System: Core User Flow Walkthrough

Preface

In the previous article we introduced the overall architecture of the single‑database order system and previewed the upcoming sharding version. Now we will step‑by‑step optimize the single‑database version.

Understanding Core Functions

Before optimizing, we must know the core functionalities and business flows of the order system. New team members should first study the wiki that contains the system architecture diagram and interface flowcharts.

The diagram shows all core functions and the technology stack used. The wiki also includes flowcharts for key interfaces, allowing quick comprehension of business processes.

User Order Placement Process

When a user selects a product and submits an order, a create‑order request is sent.

The request first reaches the Controller, which forwards it to the Service. The Service generates an order number, assembles order and order‑item data, then passes it to the Repository. The Repository uses a Mapper to persist the data in the database.

User Order List Query Process

After placing orders, users can query their order list.

The query request goes to the Controller, then to the Service and Repository, which uses the Mapper to retrieve all orders from the database and returns the list to the user.

User Order Detail Query Process

To view details of a specific order, the request follows a similar path.

The Controller forwards the request to the Service, which calls the Repository with the order ID. The Repository queries the order and its items via the Mapper and returns the details to the user.

User Cancel Order Process

Users can also cancel an order.

The cancel request is handled by the Controller, passed to the Service, which instructs the Repository to update the order status through the Mapper, effectively cancelling the order.

Conclusion

The C‑side (user side) flows have been covered. The B‑side (merchant side) provides similar functionalities such as viewing order lists, order details, and accepting or rejecting orders, which are also supported by the system. The wiki also contains the Git repository address for the code, enabling developers to clone the project and study the implementation alongside the flowcharts.