多行（结果集）拼接字符串
SQL Server版：

select stuff( (select  ','+odr.ccontact from t_order odr join t_order_tour tot on tot.uteamid='A52D1FB4-64B2-4C04-AD6B-05BC4959BD21' and odr.uid=tot.uorderid for xml path('')),1,1,'') 

Oracle：
SYS_CONNECT_BY_PATH
START WITH pid IS NULL CONNECT BY NOCYCLE PRIOR NO = pid

MySQL：
group_concat

详细可参考http://www.cnblogs.com/kiant71/archive/2010/04/09/1752006.html