Oracle Cannot Update TOP N Issue, 请专家解答

大家好

上周写了匿名方法一文,很多读者,很高兴,相信我们已经从大伙的回复中,对.NET又有了更深刻的认识.

好,现在说主题,各类数据库都有相应更新本表top n的方案.现在我一一举例

首先看表结构如下:

数据库以及表创建命令初始化数据库语句

1 CREATE TABLE student( 2 id varchar(256)   NOT NULL, 3 name varchar(256)   NULL, 4 age int NULL)

 

 1 insert into student values('001','wfg',20);  2 insert into student values('002','lxx',21);  3 insert into student values('003','wly',3);  4 insert into student values('004','jcj',60);  5 insert into student values('005','wss',60);  6 insert into student values('006','xsm',60);  7 insert into student values('007','lcf',60);  8 insert into student values('008','wjy',35);  9 insert into student values('009','hyf',35); 10 insert into student values('010','lwl',12);

 表格结构如下: 

ID Name Age
001 wfg 20
002 lxx 21
003 wly 3
004 jcj 60
005 wss 60
006 xsm 60
007 lcf 60
008 wjy 35
009 hyf 35
010 hwl 12

需求如下:按姓名顺序后,更新前5个的年龄为100岁,如何办到.

首先说下MSSQL 

1 --方案1失败
2 update top(5) student set age = 100  order by name; 3 --方案2ok
4 update  student set age = 100 where id in (select top 5 id from student order by name ); 5 select top(5) * from student order by name;

很成功,干得漂亮!

接下来我们看看MYSQL呢,拭目以待...

1 update student set age = 100  order by name limit 5; 2 select * from student order by name limit 5;

 Good news, MySql干得不错,

接下来我们再看看oracle呢?

1 --方式1失败
2 update student set age = 100 where  rownum <5 order by name ; 3 commit; 4 --方式2失败
5 update student set age = 100 where id in (select id from student  where rownum<5 order by name); 6 commit; 7 select * from student where rownum<5 order by name;

 目前为此,还没有在oracle里找到办法,请数据库专家指导,感谢为盼!

 

 

 

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