sql关于雷同父ID最多取3记录

sql关于相同父ID最多取3记录
表 imginfo
id fid miaoshu
1 3 aaaaaaa
2 3 sssssss
3 3 fffff
4 4 uuuuuuuu
5 5 gfgfgfgfgf
6 5 ddfdfdfd
7 9 fdffdfd
8 9 dfdfdfd
9 9 dfdfdf
10 9 popopop
11 3 tgtrtyrtyry
12 5 fdsjfdfdl

SELECT * FROM `imginfo` WHERE fid in(3,5,9) ORDER BY `id` DESC
上面这条语句fid 3,5,9全部内容都获取了。

现在我只想每条相同fid最多获取3条，排序不变，sql语句怎么写？
请大家指教请高人指教。不胜感激！

------解决方案--------------------

select a.* from imginfo a where 3 > (select count(*) from imginfo where fid = a.fid and id > a.id and fid in(3,5,9)) and fid in(3,5,9) order by a.fid,a.id