You can classify data based on the impact of data integrity, accuracy, consistency, and timeliness on your business.

Data in class A1 has destructive impact on business, data in class A2 has major impact on global business, data in class A3 has major impact on some business, data in class A4 has minor impact on business, and data in class Ax has unknown impact on business. The importance of data in classes A1, A2, A3, A4, and Ax decreases in sequence.

You need to sort the application that consumes tables in each data flow. Then, you can determine the data class of the application and tag the entire data flow with the data class. In this tutorial, the online operation analysis platform runs only one application named PV_UV_Region. The application collects statistics on and displays the number of page views (PVs) and unique visitors (UVs) of a website by terminal type and region. Assume that the data collected by the application affects major business decisions of the entire enterprise. You can specify A2 as the data class of the application. Then, you can tag all tables in the data flow with A2-PV_UV_Region.
Note Currently, MaxCompute does not provide any tools for you to tag tables with data classes. You can use a third-party tagging tool.