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

CREATE TABLE student(
id varchar(256)   NOT NULL,
name varchar(256)   NULL,
age int NULL)

 

insert into student values('001','wfg',20);
insert into student values('002','lxx',21);
insert into student values('003','wly',3);
insert into student values('004','jcj',60);
insert into student values('005','wss',60);
insert into student values('006','xsm',60);
insert into student values('007','lcf',60);
insert into student values('008','wjy',35);
insert into student values('009','hyf',35);
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 

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

update student set age = 100  order by name limit 5;
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？

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