select rownum,t1.* from
(select * from emp order by empno) t1
where rownum<=21

------解决方案--------------------
limit好像是sql server的
推荐分析函数
select *
 from (select t.*, row_number() over(order by empno) as rn from emp t)
  where rn between 5 and 10

------解决方案--------------------
这个  只是取了个具体值而已  如果要达到分页效果 可以写存储  或者在程序里面设置2参数  

SQL code

select rownum,t1.* from
(select * from emp order by empno) t1
where rownum >= 21*(x-1) and rownum <=21*x

------解决方案--------------------
分页不要用SQL，用前台编程工具实现吧。