百万级数据下几种SQL性能测试

发表于:2012-11-29来源:博客园作者:East神奇点击数: 标签:性能测试
百万数据下几种SQL性能测试. 今天闲来学习了一下SQL性能优化方面的知识,有以下学习收获,欢迎大家指点。 测试环境:90W,单条记录约3KB,数据库:MSSQL2005 测试前清除缓存

  今天闲来学习了一下SQL性能优化方面的知识,有以下学习收获,欢迎大家指点。

  测试环境:90W,单条记录约3KB,数据库:MSSQL2005

  测试前清除缓存

  DBCC FREEPROCCACHE

  DBCC DROPCLEANBUFFERS

  一、翻页性能测试

  1、Top

  select top 10 * from message where id not in (select top 20 id frommessage where classid=77 order by id desc ) and classid=77 order by id desc

  2、Max/Top

  select top 10 * from message where id <(select min(id) from messagewhere id in(select top 20 id from message where classid=77 order by iddesc) ) and classid=77 order by id desc

  3、row_number

  select top 10 * from (select row_number()over(order by id desc) rownumber,*from message where classid=77)a where classid=77 and rownumber>20

MsSql翻页性能测试

ID列索引

Top

Max/Top

row_number()

无索引

cpu

reads

duration

0

893

65

cpu

reads

duration

0

590

70

cpu

reads

duration

0

512

67

聚焦索引

cpu

reads

duration

0

37

66

cpu

reads

duration

0

98

64

cpu

reads

duration

0

28

67

非聚焦索引

cpu

reads

duration

0

895

63

cpu

reads

duration

0

592

66

cpu

reads

duration

0

514

66

原文转自:http://www.ltesting.net