Question

oracle中怎么先排序然后再从排序后的数据中取前几条

Answer 1

方法是：

select * from (select * from t order by col1) where rownum<10

选取排序后的前N条记录：

1. Sql代码

select top 3 e_name from ptemp.cuishen_temp_20100707   order by id  

select top 3 e_name from ptemp.cuishen_temp_20100707 order by id

Sql代码

select top 3 * from ptemp.cuishen_temp_20100707   order by id  

select top 3 * from ptemp.cuishen_temp_20100707 order by id

2.分页查询

可以用row_number关键字来进行分页查询，例如：

Sql代码

select * from ptemp.cuishen_temp_20100707   qualify row_number() over(order by id) >= 2 and row_number() over(order by id) <= 5  

select * from ptemp.cuishen_temp_20100707 qualify row_number() over(order by id) >= 2 and row_number() over(order by id) <= 5

Answer 2

select * from (select * from t order by col1) where rownum<10;