使用SQL语句去掉重复的记录【两种方法】

delete from 表 where id not in  
(select max(id) from 表 group by mobilePhone,officePhone,email )  
or 
delete from 表 where id not in  
 (select min(id) from 表 group by mobilePhone,officePhone,email ) 

delete from 表 where id not in 
(select max(id) from 表 group by mobilePhone,officePhone,email ) 
or 
delete from 表 where id not in 
 (select min(id) from 表 group by mobilePhone,officePhone,email ) 

//查询出唯一数据的ID,并把他们导入临时表tmp中  
select min(id) as mid into tmp from 表 group by mobilePhone,officePhone,email  
 //查询出去重后的数据并插入finally表中  
insert into finally select (除ID以外的字段) from customers_1 where id in (select mid from tmp) 

//查询出唯一数据的ID,并把他们导入临时表tmp中 
select min(id) as mid into tmp from 表 group by mobilePhone,officePhone,email 
 //查询出去重后的数据并插入finally表中 
insert into finally select (除ID以外的字段) from customers_1 where id in (select mid from tmp) 

delete tmp from(  
select row_num = row_number() over(partition by 字段，字段 order by 时间 desc)  
 from 表 where 时间> getdate()-1  
 ) tmp  
 where row_num > 1 
delete tmp from( 
select row_num = row_number() over(partition by 字段，字段 order by 时间 desc) 
 from 表 where 时间> getdate()-1 
 ) tmp 
 where row_num > 1 

delete from 表 where 主键ID not in(  
select max(主键ID) from 表 group by 需要去重的字段 having count(需要去重的字段)>=1  
 ) 
delete from 表 where 主键ID not in( 
select max(主键ID) from 表 group by 需要去重的字段 having count(需要去重的字段)>=1 
 ) 

delete top(2) from 表  
   where not exists (select 主键ID  
 from #tmp where #tmp.主键ID=表.主键ID)