教你轻松掌握随机抽取记录的方法

     来源：赛迪网    作者：liumingzhao

问：能否给我介绍一种随机抽取记录的方法？

答：以下代码以抽取6条为例：

create table t as select * from 
all_objects where rownum <= 5000;
set timing on
select object_name, object_id
from ( select object_name, object_id
from t
where object_name like '%%'
order by dbms_random.random )
where rownum <= 6;
select object_name, object_id
from ( select object_name, object_id
from t sample ( 1 )
where object_name like '%%'
order by dbms_random.random )
where rownum <= 6;