【SQL语句】如何根据需求除去某列重复结果

【SQL语句】怎么根据需求除去某列重复结果
问题描述如下：
现在的语句是

SQL code

select recvperson,sendTime,sendperson from ofHistroy where sendperson='admin' order by sendTime desc;

得到的结果是
+----------------------+---------------------+------------+
| recvperson | sendTime | sendperson |
+----------------------+---------------------+------------+
| 13012345678@ooooooo | 2012-08-28 12:03:31 | admin |
| 13112345678@ooooooo | 2012-08-28 12:01:31 | admin |
| 13012345678@ooooooo| 2012-08-28 11:56:41 | admin |
| 13112345678@ooooooo | 2012-08-28 10:47:09 | admin |
| 13212345678@ooooooo | 2012-08-28 10:40:58 | admin |
| admin@ooooooo | 2012-08-28 10:33:17 | admin |
| 13212345678@ooooooo | 2012-08-28 10:17:31 | admin |
| 13212345678@ooooooo | 2012-08-27 17:17:44 | admin |
| 13212345678@ooooooo | 2012-08-27 17:14:59 | admin |
| 13212345678@ooooooo | 2012-08-27 17:14:58 | admin |
| 13212345678@ooooooo | 2012-08-27 17:14:57 | admin |
| 13212345678@ooooooo | 2012-08-27 17:14:55 | admin |
+----------------------+---------------------+------------+
12 rows in set

预期结果是：
+----------------------+---------------------+------------+
| recvperson | sendTime | sendperson |
+----------------------+---------------------+------------+
| 13012345678@ooooooo | 2012-08-28 12:03:31 | admin |
| 13112345678@ooooooo | 2012-08-28 12:01:31 | admin |


| 13212345678@ooooooo| 2012-08-28 10:40:58 | admin |
| admin@ooooooo | 2012-08-28 10:33:17 | admin |
+----------------------+---------------------+------------+

需求说明：
1.查询到的recvperson无重复；
2.按照sendTime降序排列；
3.sendperson限制为admin。



[解决办法]
试试这个：

SQL code

select recvperson, max(sendTime) as sendTime,sendperson from ofHistroy where sendperson='admin' group by recvperson order by sendTime desc; 

 

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