db2 ROW_NUMBER() OVER() oracle 分页:

http://zhidao.baidu.com/link?url=sg9o3Rsdaf3yrWsWHh8uZ294tgBWArYNtPaUkb6lpU1WKBcxA9uGdQMjbNixxN1f37Hnw0IPeMhixxxugcduVa

db2:

 order by 语句最后执行。over（）函数意思是根据创建时间createtime 升序的给每行标号，取得结果集然后再根据order by CREATETIME 降序排列，最后取出10到20条

   select *

 from

 (  select rownumber() over(order by a.CREATETIME asc  ) as rowid,a.createtime from (

          select * from WK_DOCUMENTLIBRARY  )a order by CREATETIME desc

 )   where rowid  between 10 and 20

oracle 分页:

select * from (select a.*,rownum rn from (select * from b)a where rownum <=endIndex )

where rn>= startIndex

1.根据ROWID来分

select * from t_xiaoxi where rowid in(select rid from (select rownum rn,rid from(select rowid rid,cid from

t_xiaoxi  order by cid desc) where rownum<10000) where rn>9980) order by cid desc;

执行时间0.03秒

2.按分析函数来分

select * from (select t.*,row_number() over(order by cid desc) rk from t_xiaoxi t) where rk<10000 and rk>9980;

执行时间1.01秒

3.按ROWNUM来分

select * from(select t.*,rownum rn from(select * from t_xiaoxi order by cid desc) t where rownum<10000) where

rn>9980;执行时间0.1秒（3个查询语句）

其中t_xiaoxi为表名称，cid为表的关键字段，取按CID降序排序后的第9981-9999条记录，t_xiaoxi表有70000多条记录

个人感觉1的效率最好，3次之，2最差