重复记录是根据单个字段(peopleId金沙js娱乐场官方网站:)来判断,重复记录是根据单个字段来判断

) from A Group By Name Having Count(,sex Having Count(,from people group by peopleId having count(peopleId) 1),from peoplewhere peopleId in (select peopleId,where peopleId in (select   peopleId from   people group by   peopleId,重复记录是根据单个字段(peopleId)来判断

在A表中存在一个字段name,而且不同记录之间的name值有可能会相同,现在就是需要查询出在该表中的各记录之间,name值存在重复的项;Select
Name,Count(*) from A Group By Name Having Count(*)
1如果还查性别也相同大则如下:Select Name,sex,Count(*) from A Group By
Name,sex Having Count(*) 1(三)方法一declare @max integer,@id
integerdeclare cur_rows cursor local for select 主字段,count(*) from
表名 group by 主字段 having count(*) ; 1open cur_rowsfetch cur_rows
into @id,@maxwhile @@fetch_status=0beginselect @max = @max -1set
rowcount @maxdelete from 表名 where 主字段 = @idfetch cur_rows into
@id,@maxendclose cur_rowsset rowcount 0

文章介绍利用having group by 及各种select in
联合查询来实现的多种不同方法的过滤重复记录的sql语名。

一:查询及删除重复记录的SQL语句
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 peopleId in (select   peopleId from people group by   peopleId  
having count(peopleId) > 1)
and rowid not in (select min(rowid) from   people group by peopleId
having count(peopleId )>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)

方法二

1、查找表中多余的重复记录,重复记录是根据单个字段来判断

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)
(二)
比方说
在A表中存在一个字段“name”,
而且不同记录之间的“name”值有可能会相同,
现在就是需要查询出在该表中的各记录之间,“name”值存在重复的项;
Select Name,Count(*) From A Group By Name Having Count(*) > 1
如果还查性别也相同大则如下:
Select Name,sex,Count(*) From A Group By Name,sex Having Count(*) >
1

有两个意义上的重复记录,一是完全重复的记录,也即所有字段均重复的记录,二是部分关键字段重复的记录,比如Name字段重复,而其他字段不一定重复或都重复可以忽略。

代码如下复制代码 select * from peoplewhere peopleId in (select peopleId
from people group by peopleId having count(peopleId) 1)

(三)
方法一
declare @max integer,@id integer
declare cur_rows cursor local for select 主字段,count(*) from 表名
group by 主字段 having count(*) >  1
open cur_rows
fetch cur_rows into @id,@max
while @@fetch_status=0
begin
select @max = @max -1
set rowcount @max
delete from 表名 where 主字段 = @id
fetch cur_rows into @id,@max
end
close cur_rows
set rowcount 0

1、对于第一种重复,比较容易解决,使用select distinct * from tableName

2、删除表中多余的重复记录,重复记录是根据单个字段来判断,只留有rowid最小的记录

方法二
"重复记录"有两个意义上的重复记录,一是完全重复的记录,也即所有字段均重复的记录,二是部分关键字段重复的记录,比如Name字段重复,而其他字段不一定重复或都重复可以忽略。
  1、对于第一种重复,比较容易解决,使用
select distinct * from tableName
  就可以得到无重复记录的结果集。
  如果该表需要删除重复的记录(重复记录保留1条),可以按以下方法删除
select distinct * into #Tmp from tableName
drop table tableName
select * into tableName from #Tmp
drop table #Tmp
  发生这种重复的原因是表设计不周产生的,增加唯一索引列即可解决。
  2、这类重复问题通常要求保留重复记录中的第一条记录,操作方法如下
  假设有重复的字段为Name,Address,要求得到这两个字段唯一的结果集
select identity(int,1,1) as autoID, * into #Tmp from tableName
select min(autoID) as autoID into #Tmp2 from #Tmp group by
Name,autoID
select * from #Tmp where autoID in(select autoID from #tmp2)
  最后一个select即得到了Name,Address不重复的结果集(但多了一个autoID字段,实际写时可以写在select子句中省去此列)
(四)
查询重复
select * from tablename where id in (
select id from tablename
group by id
having count(id) > 1
)

就可以得到无重复记录的结果集。

代码如下复制代码 delete from people where peopleId in (select peopleId
from people group by peopleId having count(peopleId) 1)and rowid not in
(select min(rowid) from people group by peopleId having count(peopleId
)1)

Reference: 

如果该表需要删除重复的记录,可以按以下方法删除select distinct * into
#Tmp from tableNamedrop table tableNameselect * into tableName from
#Tmpdrop table #Tmp

3、查找表中多余的重复记录

发生这种重复的原因是表设计不周产生的,增加唯一索引列即可解决。

代码如下复制代码 select * from vitae awhere (a.peopleId,a.seq) in
(select peopleId,seq from vitae group by peopleId,seq having count(*)
1)

2、这类重复问题通常要求保留重复记录中的第一条记录,操作方法如下

4、删除表中多余的重复记录,只留有rowid最小的记录

假设有重复的字段为Name,Address,要求得到这两个字段唯一的结果集select
identity(int,1,1) as autoID, * into #Tmp from tableNameselect
min(autoID) as autoID into #Tmp2 from #Tmp group by Name,autoIDselect
* from #Tmp where autoID in(select autoID from #tmp2)

代码如下复制代码 delete from vitae awhere (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)

最后一个select即得到了Name,Address不重复的结果集

5、查找表中多余的重复记录,不包含rowid最小的记录

(四)查询重复select * from tablename where id in (select id from
tablename group by id having count(id) 1

代码如下复制代码 select * from vitae awhere (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)