We built a messenger app, the client can generate the message row locally and cache it immediately upon submitting the row without waiting for the response from

We built a messenger app, the client can generate the message row locally and cache it immediately upon submitting the row without waiting for the response from the server. As the primary key can be generated client side (it’s a UUID, it’s quasi guaranteed to be unique), there’s no clash with existing IDs server side. By using the optimistic response pattern the message appears in the frontend immediately. Once the response for inserting the row comes back, the message can be updated in case the server decided to set additional columns — all with the same message ID which the server gladly accepted. Wonderful.