一个数据库的面试题! 一个学生表Student(s_id,s_name)存在很多完全一样的记录,怎么把它们删除. 解决方案 » 免费领取超大流量手机卡,每月29元包185G流量+100分钟通话, 中国电信官方发货 delete student where rowid not in (select max(rowid) from student group by s_id,s_name);commit; DELETE student t WHERE ROWID != (SELECT MAX(ROWID) FROM student t WHERE a.student_id = t.student_id); with leno as(select s_id,rownumber()over(partition by s_id,s_name order by s_id,s_name) rowid from student)delete from leno where rowid >= 2 用ROWID删除时最快的了结帖率:102.17% 强 with leno as(select s_id,rownumber()over(partition by s_id,s_name order by s_id,s_name) rowid from student)delete from leno where rowid >= 2 dataguard主备切换失败,主机永远处于STANDBY状态了 解释一下SQL的含义 orcal新手求解 这样的trigger如何写? 两个数据库的不同用户间,如何进行表的同步? 有关TCP协议中的端口号和其他端口的区别?解析 我想得到其中depart_id=1的记录总条数,请问该怎么得到?急,谢谢! 关于配置数据库的问题 天啊,在什么地方字定义游标变量?!! 如何将一个Oracle的数据文件挂到数据库上 为什么停止OracleDBConsole服务,数据库就变快了 能否读取ORACLE表中的备注信息?
WHERE ROWID != (SELECT MAX(ROWID) FROM student t WHERE a.student_id = t.student_id);
(select s_id,rownumber()over(partition by s_id,s_name order by s_id,s_name) rowid from student
)
delete from leno
where rowid >= 2
(select s_id,rownumber()over(partition by s_id,s_name order by s_id,s_name) rowid from student
)
delete from leno
where rowid >= 2