Can you add an if statement in ORDER BY?

Question

I am trying to achieve the following:

I have a single ORDER BY statement which could vary depending on the value stored in Column A.

For example:

if

Answer 1

Use the CASE statement.

Example from http://dev.mysql.com/doc/refman/5.0/en/control-flow-functions.html:

SELECT id, first_name, last_name, birthday
FROM table
ORDER BY
-- numeric columns
CASE _orderby WHEN 'id' THEN id END ASC,
CASE _orderby WHEN 'desc_ id' THEN id END DESC,
-- string columns
CASE _orderby WHEN 'first_name' THEN first_name WHEN 'last_name' THEN last_name END ASC,
CASE _orderby WHEN 'desc_first_name' THEN first_name WHEN 'desc_last_name' THEN last_name END DESC,
-- datetime columns
CASE _orderby WHEN 'birthday' THEN birthday END ASC,
CASE _orderby WHEN 'desc_ birthday' THEN birthday END DESC;