分享SQL Server删除重复行的6个方法

1.如果有ID字段，就是具有唯一性的字段

复制代码代码如下:

delect table where id not in (
select max(id) from table group by col1,col2,col3…
)

group by 子句后跟的字段就是你用来判断重复的条件，如只有col1，那么只要col1字段内容相同即表示记录相同。

2. 如果是判断所有字段也可以这样

复制代码代码如下:

select * into #aa from table group by id1,id2,….
delete table
insert into table
select * from #aa

3. 没有ID的情况

复制代码代码如下:

select identity(int,1,1) as id,* into #temp from tabel
delect # where id not in (
select max(id) from # group by col1,col2,col3…)
delect table
inset into table(…)
select ….. from #temp

4. col1+’,’+col2+’,’…col5 联合主键

复制代码代码如下:

select * from table where col1+’,’+col2+’,’…col5 in (
select max(col1+’,’+col2+’,’…col5) from table
where having count(*)>1
group by col1,col2,col3,col4
)

group by 子句后跟的字段就是你用来判断重复的条件，如只有col1，那么只要col1字段内容相同即表示记录相同。

复制代码代码如下:

select identity(int,1,1) as id,* into #temp from tabel
select * from #temp where id in (
select max(id) from #emp where having count(*)>1 group by col1,col2,col3…)

复制代码代码如下:

select distinct * into #temp from tablename
delete tablename
go
insert tablename select * from #temp Sqlclub
go
drop table #temp

以上就是SQL Server删除重复行的方法介绍。