1. 按照tname排序,查询前10条数据

select id,tname from (select id,name from student order by tname) where rownum<=10 ;

2. 查询第100-150条记录

　　1. 最佳选择：利用分析函数

       row_number() over ( partition by col1 order by col2 )                               

　　比如想取出100-150条记录,按照tname排序
　　

 select tname,tabtype from (                               

     select tname,tabtype,row_number() over ( order by tname ) rn from tab                

) where rn between 100 and 150;

　　2. 使用rownum 虚列

select tname,tabtype from (                    

      select tname,tabtype,rownum rn from tab where rownum <= 150                  

) where rn >= 100;