用逗号连接就行了， 还可以分别设置升序降序

order by DECODE(AA,'A','1','B','2','C','3','D','4') desc,DECODE(BB,'D','1','C','2','B','3','A','4') asc

1、mysql自定义排序，指定排序输出：

SELECT 

CASE WHEN ajj_whcd="" then "未知"

     WHEN ajj_whcd IN ("初中", "中学") THEN "初中"

     WHEN ajj_whcd IN ("中专","中技","中专(中技)", "中师","技工","技校","普高","职专","职中", "高中","高中?") THEN "高中"

     WHEN ajj_whcd IN ("专科", "大专", "大专?", "职高", "大专毕业", "高技", "高职") THEN "大专"

     WHEN ajj_whcd IN ("本科","本科?","学士", "理科","函授本科", "大学","大学本科") THEN "本科"

     ELSE "研究生" END AS whcd, count(ajj_sfzh)

FROM yw_ajj_saqscjdglj_aqscr 

GROUP BY whcd

order by field(whcd,"初中","高中", "大专","本科","研究生","未知")

select 

DECODE(AA,'A','1','B','2','C','3','D','4') px1,

DECODE(BB,'D','1','C','2','B','3','A','4') px2

from 

table

order by px1,px2