I would like to ask, this table
If you group yourself with commands, the result is incorrect.
The result is displayed as qiu 42 (should be liu 42). How is this displayed
I wrote it myself.
Only one category of inside can be displayed. How can the maximum age of all categories of inside be displayed?
If it is written like this, it will be a screenshot like this.
SELECT id, name, max(age), class FROM (SELECT * FROM test ORDER BY age DESC) T GROUP BY class