SQL 删除重复数据

--查询重复的记录并显示
select * from [DVP_OF].[dbo].[OF_Ofddntval_dvp]
where (Fundcd+Clsdt+CAST(Naps as nvarchar(100))+CAST(Accnav1 as nvarchar(100))) in
  (SELECT  (Fundcd+Clsdt+CAST(Naps as nvarchar(100))+CAST(Accnav1 as nvarchar(100)))
  FROM OF_Ofddntval_dvp
  GROUP BY Fundcd,Clsdt,Naps,Accnav1
  HAVING COUNT (*) >1)
 and Id not in
  (SELECT  MIN(Id)
  FROM OF_Ofddntval_dvp
  GROUP BY Fundcd,Clsdt,Naps,Accnav1
  HAVING COUNT (*) >1)
 
--删除重复的记录
delete from [DVP_OF].[dbo].[OF_Ofddntval_dvp]
where (Fundcd+Clsdt+CAST(Naps as nvarchar(100))+CAST(Accnav1 as nvarchar(100))) in
  (SELECT  (Fundcd+Clsdt+CAST(Naps as nvarchar(100))+CAST(Accnav1 as nvarchar(100)))
  FROM OF_Ofddntval_dvp
  GROUP BY Fundcd,Clsdt,Naps,Accnav1
  HAVING COUNT (*) >1)
 and Id not in
  (SELECT  MIN(Id)
  FROM OF_Ofddntval_dvp
  GROUP BY Fundcd,Clsdt,Naps,Accnav1
  HAVING COUNT (*) >1)
用SQL语句,删除掉重复项只保留一条
在几千条记录里,存在着些相同的记录,如何能用SQL语句,删除掉重复的呢
1、查找表中多余的重复记录,重复记录是根据单个字段(peopleId)来判断
select * from people
where peopleId in (select peopleId from people group by peopleId having count(peopleId) > 1)

2、删除表中多余的重复记录,重复记录是根据单个字段(peopleId)来判断,只留有rowid最小的记录
delete from people
where   peopleName in (select peopleName    from people group by peopleName      having count(peopleName) > 1)
and   peopleId not in (select min(peopleId) from people group by peopleName     having count(peopleName)>1)

3、查找表中多余的重复记录(多个字段)
select * from vitae a
where (a.peopleId,a.seq) in (select peopleId,seq from vitae group by peopleId,seq having count(*) > 1)

4、删除表中多余的重复记录(多个字段),只留有rowid最小的记录
delete from vitae a
where (a.peopleId,a.seq) in (select peopleId,seq from vitae group by peopleId,seq having count(*) > 1)
and rowid not in (select min(rowid) from vitae group by peopleId,seq having count(*)>1)

5、查找表中多余的重复记录(多个字段),不包含rowid最小的记录
select * from vitae a
where (a.peopleId,a.seq) in (select peopleId,seq from vitae group by peopleId,seq having count(*) > 1)
and rowid not in (select min(rowid) from vitae group by peopleId,seq having count(*)>1)  

6.消除一个字段的左边的第一位:

update tableName set [Title]=Right([Title],(len([Title])-1)) where Title like '村%'

7.消除一个字段的右边的第一位:

update tableName set [Title]=left([Title],(len([Title])-1)) where Title like '%村'

8.假删除表中多余的重复记录(多个字段),不包含rowid最小的记录
update vitae set ispass=-1
where peopleId in (select peopleId from vitae group by peopleId

 

/* 将过滤的数据放入临时表*/
select distinct * 
into #temp
from t1
order by s_id  

/*删除原表的数据*/
delete from t1

/*将甩选的数据插入原表
insert 
t1
select *
from #temp

/*删除临时表
drop table #temp
select * from t1

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