www.1862.net > sql数据库中出现重复行数据,如何删除这些重复记录?

sql数据库中出现重复行数据,如何删除这些重复记录?

delete from TABLE_name t1 where t1.rowid > (select min(rowid) from TABLE_name t2 where t1.name = t2.name group by name having count(name) > 1); 肯定没问题的哈

代码如下: DELETE FROM zkw_kehu WHERE (k_cname IN (SELECT k_cname FROM zkw_kehu GROUP BY k_cname HAVING COUNT(k_cname) > 1)) AND (k_id NOT IN (SELECT MIN(k_id) FROM zkw_kehu GROUP BY k_cname HAVING COUNT(k_cname) > 1))

1、必须保证表中有主键或者唯一索引,或者某列数据不能重复。只有这样,才可能使用一句SQL来实现。否则只能考虑其它办法。下面的语句,假定BB列是不重复的,删除后保存BB列值最大的那条记录。 delete from 表 where aa in (select aa from 表 gr...

表结构如下 test (id int,name varchar2,age int) 1 张三 10 2 张三 10 3 李四 20 4 李四 20 5 王五 19 除了id外其他字段全部相同的记录只保留一条 删除多余的记录 delete test where id not in(select max(id) from test group by name,age) 如...

新建一个表b ,insert into b select distinct * from a,然后把a表删掉,b表改名

删除数据库用drop database 语句删除或在图形界面删除都可。如,删除一个叫test的数据库,语句删除方法如下:drop database test;图形界面:1、进入SQL Server Management Studio。2、左边列表找到“数据库”。3、在要删除的数据库上点鼠标右键,...

userId: user id url: url visited by the user SELECT userId, COUNT(DISTINCT url) FROM tab GROUP BY userId ORDER BY COUNT(DISTINCT url) DESC

找到最大的rowid即可。 Sql代码: alter proc getNotDupData as --clear temp table delete ODS.dbo.Agent delete from stage.dbo.tmpDup delete from stage.dbo.tmpRowNo delete from stage.dbo.tmpMaxRowNo --create dup table insert into st...

select * from tablename where 重复字段1 in (select 重复字段1 from tablename group by 重复字段1,重复字段2 having count(*)>1)

网站地图

All rights reserved Powered by www.1862.net

copyright ©right 2010-2021。
www.1862.net内容来自网络,如有侵犯请联系客服。zhit325@qq.com