MYSQL Order By Sum of Columns

Any idea on how to order the results of a MYSQL query开发者_如何学编程 by the sum of two columns rather than by a single column?

Select * FROM table ORDER BY (col1+col2) desc

I know that won't work., but I hope it conveys what I want to do fairly well.

Thanks!

Why not try before concluding it doesn't work? In point of fact, it does.

Suppose you have a table named 'Students'

Now you want to know the total marks scored by each student. So, type the following query

SELECT Name, S1, S2, SUM(S1+S2) AS TOTAL
FROM Students
GROUP BY Name, S1, S2
ORDER BY Total;

You will get the following result.

I think you should be able to do

SELECT *, col1+col2 as mysum ORDER BY mysum

Which is essentially the same as you already have

I can confirm this is NOT working in some cases. Check if some value is NULL

Select * FROM table ORDER BY (IFNULL(col1,0)+IFNULL(col2,0)) desc

The query you wrote should work just fine, you can have any expression in the ORDER BY clause.