检索 id = 2 or id = 5 or id = 9 or id = 56 or id = 38.
然后按照 2 ， 5， 9， 56， 38 这个顺序排列，这是题目要求
以下为解决方案：
1.SELECT * FROM `test` WHERE `id` IN(2,5,9,56,38) ORDER BY FIELD(`id`,2,5,9,56,38); (方案出自：http://www.phptext.net/article_view.php?id=199)
2.select * case `id` when 38 then 57 else `id` end as myorder from test where find_in_set(`id`,2,5,9,56,38) order by myorder
3.(此种不是很明白）
(SELECT * FROM `account_biz` where id = 2)
UNION (select * from account_biz where id = 5)
UNION (select * from account_biz where id = 9)
UNION (SELECT * FROM `account_biz` where id = 56)
UNION (select * from account_biz where id = 38);
MySQL Field排序法
原文：http://www.cnblogs.com/myphper/p/4284576.html
