(SELECT `size`, `type` FROM `table` WHERE `type`='a' ORDER BY `size` ASC)
UNION ALL
(SELECT `size`,`type` FROM `table` WHERE `type`='b' ORDER BY `size` DESC)
(SELECT `size`, `type` FROM `table` WHERE `typ (SELECT `size`, `type` FROM `table` WHERE `type`='a' ORDER BY `size` ASC)
UNION ALL
(SELECT `size`,`type` FROM `table` WHERE `type`='b' ORDER BY `size` DESC)
(SELECT `size`, `type` FROM `table` WHERE `typ