PLSQL根据页码及每页大小获取数据

错误示例

select *          from (select * from FUSION_ITEM t order by item_id)         where rownum <= v_page * size and rownum>(page-1)*size;

正确示例

 select item_id,item_name,long_description,item_desc  from (  select item_id,item_name,long_description,item_desc , rownum  row_no          from (select * from FUSION_ITEM t order by item_id)         where rownum <= v_page * v_size ) a where row_no  > = (v_page-1)*size+1;