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原标题:表中重复记录语句,查询和删除重复字段数据的方法

浏览次数:186 时间:2020-05-08

最后一个select即得到了Name,Address不重复的结果集

(三)方法一复制代码 代码如下: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,可以按以下方法删除复制代码 代码如下:select distinct * into #Tmp from tableNamedrop table tableNameselect * into tableName from #Tmpdrop 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复制代码 代码如下: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) 最后一个select即得到了Name,Address不重复的结果集(四)查询重复复制代码 代码如下:select *葡京正网网投, from tablename where id in (select id from tablenamegroup by idhaving count(id) 1)

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复制代码 代码如下: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) 最后一个select即得到了Name,Address不重复的结果集

如果该表需要删除重复的记录,可以按以下方法删除

例如: id name value 1 a pp 2 a pp 3 b iii 4 b pp 5 b pp 6 c pp 7 c pp 8 c iii id是主键 要求得到这样的结果 id name value 1 a pp 3 b iii 4 b pp 6 c pp 8 c iii

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 distinct * into #Tmp from tableNamedrop table tableNameselect * into tableName from #Tmpdrop table #Tmp

方法1复制代码 代码如下:delete YourTable where [id] not in ( select max([id]) from YourTable group by (name + value)) 方法2复制代码 代码如下:delete a from 表 a left join( select id=min(id) from 表 group by name,value )b on a.id=b.id where b.id is null

1、对于第一种重复,比较容易解决,使用复制代码 代码如下:select distinct * from tableName 就可以得到无重复记录的结果集。

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)

查询及删除重复记录的SQL语句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来判断复制代码 代码如下:select * from peoplewhere 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来判断,只留有rowid最小的记录复制代码 代码如下:delete from peoplewhere 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复制代码 代码如下:select * from vitae awhere (a.peopleId,a.seq) in (select peopleId,seq from vitae group by peopleId,seq having count(*葡京网投哪个正规,) 1)4、删除表中多余的重复记录,只留有rowid最小的记录复制代码 代码如下: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)5、查找表中多余的重复记录,不包含rowid最小的记录复制代码 代码如下: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)(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

)1)3、查找表中多余的重复记录 复制代码 代码如下:select * from vitae awhere (a.peopleId,a.seq) in (select peopleId,seq from vitae group by peopleId,seq having

代码如下复制代码 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)

(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来判断,只留有rowid最小的记录复制代码 代码如下:delete from people where peopleId in (select peopleId from people group by peopleId having count

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。

(四)查询重复复制代码 代码如下:select * from tablename where id in (select id from tablename group by id having count(id) 1)

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

count(*) 1)4、删除表中多余的重复记录,只留有rowid最小的记录复制代码 代码如下:delete from vitae awhere (a.peopleId,a.seq) in (select peopleId,seq from vitae group by peopleId,seq having

(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;

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

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

代码如下复制代码 select distinct * from tableName

(peopleId) 1)and rowid not in (select min(rowid) from people group by peopleId having count(peopleId

代码如下复制代码 Select Name,Count(*) From A Group By Name 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

3、查找表中多余的重复记录

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,不包含rowid最小的记录复制代码 代码如下:select * from vitae awhere (a.peopleId,a.seq) in (select peopleId,seq from vitae group by peopleId,seq having

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)

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;复制代码 代码如下:Select Name,Count(*) From A Group By Name Having Count(*) 1如果还查性别也相同大则如下:复制代码 代码如下:Select Name,sex,Count(*) From A Group By Name,sex Having Count(*) 1(三)方法一复制代码 代码如下:declare @max integer,@id integerdeclare cur_rows cursor local for select 主字段,count(*) from 表名 group by 主字段 having

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。

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

5、查找表中多余的重复记录,不包含rowid最小的记录

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方法二

代码如下复制代码 Select Name,sex,Count(*) From A Group By Name,sex Having Count(*) 1

(三)方法一

就可以得到无重复记录的结果集。

4、删除表中多余的重复记录,只留有rowid最小的记录

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

代码如下复制代码 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 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)

1、对于第一种重复,比较容易解决,使用

方法二

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。

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

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

如果还查性别也相同大则如下:

(四)查询重复

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)

代码如下复制代码 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

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