Example of order by case when in MYSQL database

Function

Course list data display

Requirement

1. Normally open classes are displayed on the front, while closed classes are displayed on the back.
2. Normal classes start in descending order of course class time
3. The completion time of the class is in reverse order.

Field

Status: class status
Start_date: course class date
End_date: end date

Statement

SELECT * FROM 'table'
Order by 'status' ASC,
Case when 'status' = 1 THEN 'start _ date' end desc,
Case when 'status' = 3 then' end _ date' end desc;