查询表内多字段同时重复记录的SQL语句

时间:2021-12-17 00:07:57

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查询表内多字段同时重复记录的SQL语句,比如现在有一人员表  (表名:peosons)

若想将姓名、身份证号、住址这三个字段完全相同的记录查询出来 

select   p1.*   from   persons   p1,persons   p2   where   p1.id<>p2.id   and   p1.cardid   =   p2.cardid   and   p1.pname   =   p2.pname   and   p1.address   =   p2.address

 

可以实现上述效果.

 

几个删除重复记录的SQL语句

 1.用rowid方法

 

2.用group by方法

 

3.用distinct方法

 

 1。用rowid方法

 

据据oracle带的rowid属性,进行判断,是否存在重复,语句如下:

查数据:

     select * from table1 a where rowid !=(select   max(rowid)  

     from table1 b where a.name1=b.name1 and a.name2=b.name2......)

删数据:

    delete   from table1 a where rowid !=(select   max(rowid)  

     from table1 b where a.name1=b.name1 and a.name2=b.name2......)

 

2.group by方法

 

查数据:

  select count(num), max(name) from student --列出重复的记录数,并列出他的name属性 

  group by num 

  having count(num) >1 --按num分组后找出表中num列重复,即出现次数大于一次 

删数据:

  delete from student 

  group by num 

  having count(num) >1

  这样的话就把所有重复的都删除了。

 

3.用distinct方法 -对于小的表比较有用

 

create table table_new as   select distinct *   from table1 minux 

truncate table table1;

insert into table1 select * from table_new;

 

 

 

查询及删除重复记录的方法大全

 

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)

 

 

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)

 

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