mysql删除重复记录的sql语句与查询重复记录(1/4)
方法1
delete yourtable
where [id] not in (
select max([id]) from yourtable
group by (name + value))
方法2
delete a
from 表 a left join(
select (id) from 表 group by name,value
)b on a.id=b.id
where b.id is null
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（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)
补充：数据库,mysql教程
