Scenario: 

I would like to get only one max value for each student ID. For example, a company needs to examine each person's attendance and identify the arrival time for being late monthly, but for the clarity of the report, it is required that if there is a duplication of the arrival time for being late, only one is identified.

Another example is a sales company that needs to mark the maximum monthly sales of each salesperson on the sales sheet and display the data during meetings. At this time, the maximum sales are duplicated, and if they are all marked, it will affect the beauty of the whole report, so only one of the duplicated maximum values should be randomly marked.

The blog is about how to use RANKX() function in three different items.