It is true that the health green code can be displayed on the ground, but when you arrive in a different place, you will have a trip. Naturally, this healthy green code may fail and cannot be displayed during this trip.
The first is to report personal health status, and the second is to master personal action track. For example, through the color of the health code, you can quickly identify whether a person has passed through provinces and cities with serious epidemics and whether he has directly or indirectly contacted infected people. Then through big data analysis, people who may be infected can be directly targeted and found. At the same time, every time the code is scanned to obtain the relevant health code, personal travel information will also be obtained by big data. If it shows that other provinces have not checked, it means the present stage (i.e. 10).