SQL重复记录查询
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)
例二:
select * from testtable
where numeber in (select number from people gro
1、查找重复记录 ①如果只是不想在查询结果中存在重复记录, 可以加Distinct select distinct * from TestTable ②如果是想查询重复的记录及其数量 select UserID,UserName,count(*) as ‘记录数’ from TestTable Group by UserID,UserName having count(*)>1 ③ID不重复, 但是字段重复的记录只显示一条 select * from TestTable where Use
MYSQL 查询和删除重复记录的方法很多,下面为您介绍几种常用的 MYSQL 查询和删除重复记录的方法,希望对您查询和删除重复数据方面能有所帮助。
SQL重复记录查询的几种方法:
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(
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 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(peopleId)来判断,只留有rowid最小的记录 代码如下:delete from people where p
–查出表中有重复的id的记录,并计算相同id的数量select id,count(id) from table group by id having(count(id)>1)
其中,group by id,是按id字段分组查询:
select id,count(id) from table group by id
可以得到各不同id的数量合计
having(count(id)>1)判断数量大于1,也就是有重复id的记录
您可能感