How to define a custom ORDER BY order in mySQL

Question

In MySQL how do I define a custom sorting order.

To try to explain what I want consider this table:

ID  Language    Text
0   ENU         a
0   JPN           


        

Answer 1

You have a couple of options offhand, the first is to change Language to be ENUM (assuming this is possible, and you only expect a few variations)

If you specify it as ENUM('ENU','JPN','DAN') then ORDER Language ASC will order in the order you specify.

The second will involve a case somewhere, i.e.

SELECT * FROM table
ORDER BY CASE Language
    WHEN 'ENU' THEN 3
    WHEN 'JPN' THEN 2
    WHEN 'DAN' THEN 1
    ELSE 0
END DESC, ID ASC

Performance-wise the ENUM method will return faster results, but be more hassle if you need to add more languages. A third option would be to add a normalisation table for the Languages however that may be overkill in this instance.