在h31bt.com网站准备采用Lucence.net来进行索引处理搜索慢问题的时候,突然发现常用的分页获取数据的row_number也支持不住了,后期查到200多万的时候非常慢(总数据有500万),经过网上查询分析一些资料后,基本上搞明白是什么原因导致的,顺便纪录一下解决方
在h31bt.com网站准备采用Lucence.net来进行索引处理搜索慢问题的时候,突然发现常用的分页获取数据的row_number也支持不住了,后期查到200多万的时候非常慢(总数据有500万),经过网上查询分析一些资料后,基本上搞明白是什么原因导致的,顺便纪录一下解决方案。
------------------------------------
网上找的几种sqlserver2005高效分页sql查询语句
top方案:
sql codeselect top 10 *
from table1
where id not in(select top 开始的位置 id from table1)
max:
sql codeselect top 10 * from
table1
where id>(select max(id)
from (select top 开始位置 id from table1order by id)tt)
row:
sql codeselect *
from (
select
row_number()over(order by tempcolumn)temprownumber,*
from
(select top 开始位置+10 tempcolumn=0,* from table1)t
)tt
where
temprownumber>开始位置
3种分页方式,分别是max方案,top方案,row方案
效率:
第1:row
第2:max
第3:top
缺点:
max:必须用户编写复杂sql,不支持非唯一列排序
top:必须用户编写复杂sql,不支持复合主键
row:不支持sqlserver2000
测试数据:
共320万条数据,每页显示10条数据,分别测试了2万页、15万页和32万页。
页码,top方案,max方案,row方案
2万,60ms,46ms,33ms
15万,453ms,343ms,310ms
32万,953ms,720ms,686ms
-----------------------------------------------
个人也是经常采用row_number来解决问题的,但是主键是以ID为主的,这次数据库表不是ID主键,,
如果使用ID来进行获取200万后面的200条数据,发现服务器上需要几分钟都不一定出来得结果
select * from (select *,row_number() over(order by ID asc) as RowNum from H31_DHT_TYPE_101_1) as a where RowNum between 2000000 and 2000200

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