在SQL中怎么删除两个表中相同的数据

1，首先创建一个表，并在表中插入重复的记录，如下图所示。

2，插入好以后就看见表中已经有重复的数据了，如下图所示。

3，接下来在删除之前我们记得一定先备份，如下图所示。

4，然后排除重复的记录可以通过distinct字段设置，如下图所示，然后将去重的数据插入到新表中。

5，接着看到数据表下面多出来一个刚建的新表，如下图所示。

6，最后打开新表，就可以看到重复的数据都没有了，如下图所示。

1、在电脑上打开要去掉重复数据的数据库，这里新建一张含有重复数据的user表。

2、输入“select * from user where name in (select name from user group by name having count(name) >1) ”sql语句，点击运行可以看到查询出了数据库中user表的重复数据。

3、通过“delete from user where   name in (select name from user group by name  having count(name) >1) ”sql语句删除姓名重复的数据。

4、也可以通过“select distinct name from user”sql语句来去掉重复数据，这里去掉了张三的重复数据。

5、通过“select distinct class from user”sql语句来去掉班级相同的重复数据。

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 peopleNamefrom 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

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