mysql排序问题

SELECT GROUP_CONCAT(DISTINCT `goods_id` ORDER BY `lv`) as ids FROM base_guild_shopids
321401,321301,222001,221701,221001,111001,511103,...SELECT DISTINCT `goods_id`,lv FROM base_guild_shop ORDER BY `lv`,goods_id DESC
goods_id | lv
321401 1
321301 1
222001 1
221701 1
221001 1
111001 1
511103 2
...为什么ids字段的排序是降序的？