Исправление NeOlip, 17.01.17 13:56 (текущая версия) :
SELECT `id`, `name`, `birthday` FROM `user` ORDER BY (ABS(DAYOFYEAR(CURDATE()) - DAYOFYEAR(`birthday`)));
Не?
Исходная версия NeOlip, 17.01.17 13:55:
SELECT `id`, `name`, `birthday` FROM `user` ORDER BY (ABS(DAYOFYEAR(curdate()) - DAYOFYEAR(`birthday`)));