MySQL Conditional Ordering

Question

Is it possible to sort this way?

Unsorted

TIMEIN                TIMEOUT
null                  6/19/2014 12:00:00
6/19/2014 08:30:00    6/19/2014 10:30:00
6/19/2014 13:00:00    null
6/19/2014 19:06:00    6/19/2014 20:36:00 

Sorted

TIMEIN                TIMEOUT
6/19/2014 08:30:00    6/19/2014 10:30:00
null                  6/19/2014 12:00:00
6/19/2014 13:00:00    null
6/19/2014 19:06:00    6/19/2014 20:36:00 

The list is sorted by TIMEIN descending. If TIMEIN is NULL, TIMEOUT will be the basis in sorting without reordering 'TIMEIN desc'.

Answer 1

There's a handy function called COALESCE in MySQL you can just drop into the ORDER BY clause.

Here is the doc for it
Here is an example

And here is what you can append to your SQL:

ORDER BY COALESCE(TIMEIN, TIMEOUT) DESC

Answer 2

ORDER BY IFNULL(TIMEIN, TIMEOUT) DESC