查询数据表里所有重复里的单条记录

测试脚本：

CREATE TABLE [dbo].[TEST](
	[ID] [int] IDENTITY(1,1) NOT NULL,
	[TID] [int] NULL,
	[Discription] [nvarchar](200) NULL
)  
--测试数据
DELETE FROM TEST
INSERT INTO TEST (TID,Discription)VALUES (1,'记录1-1')
INSERT INTO TEST (TID,Discription)VALUES (1,'记录1-2')
INSERT INTO TEST (TID,Discription)VALUES (1,'记录1-3')
INSERT INTO TEST (TID,Discription)VALUES (1,'记录1-4')
INSERT INTO TEST (TID,Discription)VALUES (1,'记录1-5')
INSERT INTO TEST (TID,Discription)VALUES (2,'记录2-1')
INSERT INTO TEST (TID,Discription)VALUES (2,'记录2-2')
INSERT INTO TEST (TID,Discription)VALUES (2,'记录2-3') 

SELECT * FROM TEST

查询结果：

TID为重复字段，现在需找出所有TID中ID字段值最大的记录。

如下图所示：

解决办法：GROUP BY() 函数+Max()函数

SELECT * FROM TEST WHERE ID IN (SELECT MAX(ID)FROM Test GROUP BY TID )