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 )