Sql server 从具有标识的SQL Server 2012表中删除重复记录

我试图复制一个场景，在这个场景中，我需要从表中删除除一行之外的所有重复行。但所有行都有一个唯一的标识列

为了让事情变得更简单，我创建了一个小的测试表student，脚本如下所示

create table student 
(
    id int,
    rollno int,
    name varchar(50),
    course varchar(50)
)
GO

insert into student values(1,1335592,'john','biology')
insert into student values(2,1335592,'john','biology')
insert into student values(3,1335592,'john','biology')
insert into student values(4,1335592,'john','biology')
insert into student values(5,1335593,'peter','biology')
insert into student values(6,1335593,'peter','biology')
insert into student values(7,1335593,'peter','biology')
GO

select * from student

id  rollno  name    course
1   1335592 john    biology
2   1335592 john    biology
3   1335592 john    biology
4   1335592 john    biology
5   1335593 peter   biology
6   1335593 peter   biology
7   1335593 peter   biology

这将生成如下表

create table student 
(
    id int,
    rollno int,
    name varchar(50),
    course varchar(50)
)
GO

insert into student values(1,1335592,'john','biology')
insert into student values(2,1335592,'john','biology')
insert into student values(3,1335592,'john','biology')
insert into student values(4,1335592,'john','biology')
insert into student values(5,1335593,'peter','biology')
insert into student values(6,1335593,'peter','biology')
insert into student values(7,1335593,'peter','biology')
GO

select * from student

id  rollno  name    course
1   1335592 john    biology
2   1335592 john    biology
3   1335592 john    biology
4   1335592 john    biology
5   1335593 peter   biology
6   1335593 peter   biology
7   1335593 peter   biology

我想在结果集中保留ID为“1”和“5”的记录，并删除所有其他内容。有没有办法做到这一点

我们将非常感谢您的帮助

谢谢 Shammas使用CTE

质疑

这是一个简单的查询

Delete from student 
where id not in (select min(id) 
                 from student 
                 group by rollno, name, course) 

你可以用 , ,

这些都会给你结果

尝试：

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请参见

谢谢乌拉斯……这对我很有效。。发布问题后，我找到了定义良好的链接。谢谢你的回复，银行漫游者。这个脚本也是正确的。很抱歉迟了答复

DELETE s
FROM student s
JOIN student s2 ON s.course = s2.course
     AND s.NAME = s2.NAME
     AND s.rollno = s2.rollno
WHERE s2.id < s.id