大数据量分页存储过程效率测试附代码
在项目中,我们经常遇到或用到分页,那么在大数据量(百万级以上)下,哪种分页算法效率最优呢?我们不妨用事实说话。
测试环境
硬件:CPU 酷睿双核T5750 内存:2G
软件:Windows server 2003 + Sql server 2005
OK,我们首先创建一数据库:data_Test,并在此数据库中创建一表:tb_TestTable
create database data_Test --创建数据库data_Test 2
GO 3
use data_Test 4
GO 5
create table tb_TestTable --创建表 6
( 7
id int identity(1,1) primary key, 8
userName nvarchar(20) not null, 9
userPWD nvarchar(20) not null, 10
userEmail nvarchar(40) null 11
) 12
GO
然后我们在数据表中插入2000000条数据:
--插入数据 2
set identity_insert tb_TestTable on 3
declare @count int 4
set @count=1 5
while @count<=2000000 6
begin 7
insert into tb_TestTable(id,userName,userPWD,userEmail) values(@count,'admin','admin888','lli0077@yahoo.com.cn') 8
set @count=@count+1 9
end 10
set identity_insert tb_TestTable off
我首先写了五个常用存储过程:
1,利用select top 和select not in进行分页,具体代码如下:
create procedure proc_paged_with_notin --利用select top and select not in 2
( 3
@pageIndex int, --页索引 4
@pageSize int --每页记录数 5
) 6
as 7
begin 8
set nocount on; 9
declare @timediff datetime --耗时 10
declare @sql nvarchar(500) 11
select @timediff=Getdate() 12
set @sql='select top '+str(@pageSize)+' * from tb_TestTable where(ID not in(select top '+str(@pageSize*@pageIndex)+' id from tb_TestTable order by ID ASC)) order by ID' 13
execute(@sql) --因select top后不支技直接接参数,所以写成了字符串@sql 14
select datediff(ms,@timediff,GetDate()) as 耗时 15
set nocount off; 16
end
2,利用select top 和 select max(列键)
create procedure proc_paged_with_selectMax --利用select top and select max(列) 2
( 3
@pageIndex int, --页索引 4
@pageSize int --页记录数 5
) 6
as 7
begin 8
set nocount on; 9
declare @timediff datetime 10
declare @sql nvarchar(500) 11
select @timediff=Getdate() 12
set @sql='select top '+str(@pageSize)+' * From tb_TestTable where(ID>(select max(id) From (select top '+str(@pageSize*@pageIndex)+' id From tb_TestTable order by ID) as TempTable)) order by ID' 13
execute(@sql) 14
select datediff(ms,@timediff,GetDate()) as 耗时 15
set nocount off; 16
end
3,利用select top和中间变量--此方法因网上有人说效果最佳,所以贴出来一同测试
create procedure proc_paged_with_Midvar --利用ID>最大ID值和中间变量 2
( 3
@pageIndex int, 4
@pageSize int 5
) 6
as 7
declare @count int 8
declare @ID int 9
declare @timediff datetime 10
declare @sql nvarchar(500) 11
begin 12
set nocount on; 13
select @count=0,@ID=0,@timediff=getdate() 14
select @count=@count+1,@ID=case when @count<=@pageSize*@pageIndex then ID else @ID end from tb_testTable order by id 15
set @sql='select top '+str(@pageSize)+' * from tb_testTable where ID>'+str(@ID) 16
execute(@sql) 17
select datediff(ms,@timediff,getdate()) as 耗时 18
set nocount off; 19
end20

4,利用Row_number() 此方法为SQL server 2005中新的方法,利用Row_number()给数据行加上索引
create procedure proc_paged_with_Rownumber --利用SQL 2005中的Row_number() 2
( 3
@pageIndex int, 4
@pageSize int 5
) 6
as 7
declare @timediff datetime 8
begin 9
set nocount on; 10
select @timediff=getdate() 11
select * from (select *,Row_number() over(order by ID asc) as IDRank from tb_testTable) as IDWithRowNumber where IDRank>@pageSize*@pageIndex and IDRank<@pageSize*(@pageIndex+1) 12
select datediff(ms,@timediff,getdate()) as 耗时 13
set nocount off; 14
end15

5,利用临时表及Row_number
create procedure proc_CTE --利用临时表及Row_number 2
( 3
@pageIndex int, --页索引 4
@pageSize int --页记录数 5
) 6
as 7
set nocount on; 8
declare @ctestr nvarchar(400) 9
declare @strSql nvarchar(400) 10
declare @datediff datetime 11
begin 12
select @datediff=GetDate() 13
set @ctestr='with Table_CTE as 14
(select ceiling((Row_number() over(order by ID ASC))/'+str(@pageSize)+') as page_num,* from tb_TestTable)'; 15
set @strSql=@ctestr+' select * From Table_CTE where page_num='+str(@pageIndex) 16
end 17
begin 18
execute sp_executesql @strSql 19
select datediff(ms,@datediff,GetDate()) 20
set nocount off; 21
end22

OK,至此,存储过程创建完毕,我们分别在每页10条数据的情况下在第2页,第1000页,第10000页,第100000页,第199999页进行测试,耗时单位:ms 每页测试5次取其平均值
| 存过 | 第2页耗时 | 第1000页耗时 | 第10000页耗时 | 第100000页耗时 | 第199999页耗时 | 效率排行 |
| 1用not in | 0ms | 16ms | 47ms | 475ms | 953ms | 3 |
| 2用select max | 5ms | 16ms | 35ms | 325ms | 623ms | 1 |
| 3中间变量 | 966ms | 970ms | 960ms | 945ms | 933ms | 5 |
| 4row_number | 0ms | 0ms | 34ms | 365ms | 710ms | 2 |
| 4临时表 | 780ms | 796ms | 798ms | 780ms | 805ms | 4 |
测试结果显示:select max >row_number>not in>临时表>中间变量
于是我对效率最高的select max方法用2分法进行了扩展,代码取自互联网,我修改了ASC排序时取不到值的BUG,测试结果:
| 2分法 | 156ms | 156ms | 180ms | 470ms | 156ms | 1* |
从测试结果来看,使用2分法确实可以提高效率并使效率更为稳定,我又增加了第159999页的测试,用时仅296ms,效果相当的不错!
下面是2分法使用select max的代码,已相当完善。
--/*-----存储过程 分页处理 孙伟 2005-03-28创建 -------*/ 2
--/*-----存储过程 分页处理 浪尘 2008-9-1修改----------*/ 3
--/*----- 对数据进行了2分处理使查询前半部分数据与查询后半部分数据性能相同 -------*/ 4

5
alter PROCEDURE proc_paged_2part_selectMax 6
( 7
@tblName nvarchar(200), ----要显示的表或多个表的连接 8
@fldName nvarchar(500) = '*', ----要显示的字段列表 9
@pageSize int = 10, ----每页显示的记录个数 10
@page int = 1, ----要显示那一页的记录 11
@fldSort nvarchar(200) = null, ----排序字段列表或条件 12
@Sort bit = 0, ----排序方法,0为升序,1为降序(如果是多字段排列Sort指代最后一个排序字段的排列顺序(最后一个排序字段不加排序标记)--程序传参如:' SortA Asc,SortB Desc,SortC ') 13
@strCondition nvarchar(1000) = null, ----查询条件,不需where 14
@ID nvarchar(150), ----主表的主键 15
@Dist bit = 0, ----是否添加查询字段的 DISTINCT 默认0不添加/1添加 16
@pageCount int = 1 output, ----查询结果分页后的总页数 17
@Counts int = 1 output ----查询到的记录数 18
) 19
AS 20
SET NOCOUNT ON 21
Declare @sqlTmp nvarchar(1000) ----存放动态生成的SQL语句 22
Declare @strTmp nvarchar(1000) ----存放取得查询结果总数的查询语句 23
Declare @strID nvarchar(1000) ----存放取得查询开头或结尾ID的查询语句 24

25
Declare @strSortType nvarchar(10) ----数据排序规则A 26
Declare @strFSortType nvarchar(10) ----数据排序规则B 27

28
Declare @SqlSelect nvarchar(50) ----对含有DISTINCT的查询进行SQL构造 29
Declare @SqlCounts nvarchar(50) ----对含有DISTINCT的总数查询进行SQL构造 30

31
declare @timediff datetime --耗时测试时间差 32
select @timediff=getdate() 33

34
if @Dist = 0 35
begin 36
set @SqlSelect = 'select ' 37
set @SqlCounts = 'Count(*)' 38
end 39
else 40
begin 41
set @SqlSelect = 'select distinct ' 42
set @SqlCounts = 'Count(DISTINCT '+@ID+')' 43
end 44

45

46
if @Sort=0 47
begin 48
set @strFSortType=' ASC ' 49
set @strSortType=' DESC ' 50
end 51
else 52
begin 53
set @strFSortType=' DESC ' 54
set @strSortType=' ASC ' 55
end 56

57

58

59
--------生成查询语句-------- 60
--此处@strTmp为取得查询结果数量的语句 61
if @strCondition is null or @strCondition='' --没有设置显示条件 62
begin 63
set @sqlTmp = @fldName + ' From ' + @tblName 64
set @strTmp = @SqlSelect+' @Counts='+@SqlCounts+' FROM '+@tblName 65
set @strID = ' From ' + @tblName 66
end 67
else 68
begin 69
set @sqlTmp = + @fldName + 'From ' + @tblName + ' where (1>0) ' + @strCondition 70
set @strTmp = @SqlSelect+' @Counts='+@SqlCounts+' FROM '+@tblName + ' where (1>0) ' + @strCondition 71
set @strID = ' From ' + @tblName + ' where (1>0) ' + @strCondition 72
end 73

74
----取得查询结果总数量----- 75
exec sp_executesql @strTmp,N'@Counts int out ',@Counts out 76
declare @tmpCounts int 77
if @Counts = 0 78
set @tmpCounts = 1 79
else 80
set @tmpCounts = @Counts 81

82
--取得分页总数 83
set @pageCount=(@tmpCounts+@pageSize-1)/@pageSize 84

85
/**//**当前页大于总页数 取最后一页**/ 86
if @page>@pageCount 87
set @page=@pageCount 88

89
--/*-----数据分页2分处理-------*/ 90
declare @pageIndex int --总数/页大小 91
declare @lastcount int --总数%页大小 92

93
set @pageIndex = @tmpCounts/@pageSize 94
set @lastcount = @tmpCounts%@pageSize 95
if @lastcount > 0 96
set @pageIndex = @pageIndex + 1 97
else 98
set @lastcount = @pagesize 99

100
--//***显示分页 101
if @strCondition is null or @strCondition='' --没有设置显示条件 102
begin 103
if @pageIndex<2 or @page<=@pageIndex / 2 + @pageIndex % 2 --前半部分数据处理 104
begin 105
if @page=1 106
set @strTmp=@SqlSelect+' top '+ CAST(@pageSize as VARCHAR(4))+' '+ @fldName+' from '+@tblName 107
+' order by '+ @fldSort +' '+ @strFSortType 108
else 109
begin 110
if @Sort=1 111
begin 112
set @strTmp=@SqlSelect+' top '+ CAST(@pageSize as VARCHAR(4))+' '+ @fldName+' from '+@tblName 113
+' where '+@ID+' <(select min('+ @ID +') from ('+ @SqlSelect+' top '+ CAST(@pageSize*(@page-1) as Varchar(20)) +' '+ @ID +' from '+@tblName 114
+' order by '+ @fldSort +' '+ @strFSortType+') AS TBMinID)' 115
+' order by '+ @fldSort +' '+ @strFSortType 116
end 117
else 118
begin 119
set @strTmp=@SqlSelect+' top '+ CAST(@pageSize as VARCHAR(4))+' '+ @fldName+' from '+@tblName 120
+' where '+@ID+' >(select max('+ @ID +') from ('+ @SqlSelect+' top '+ CAST(@pageSize*(@page-1) as Varchar(20)) +' '+ @ID +' from '+@tblName 121
+' order by '+ @fldSort +' '+ @strFSortType+') AS TBMinID)' 122
+' order by '+ @fldSort +' '+ @strFSortType 123
end 124
end 125
end 126
else 127
begin 128
set @page = @pageIndex-@page+1 --后半部分数据处理 129
if @page <= 1 --最后一页数据显示 130
set @strTmp=@SqlSelect+' * from ('+@SqlSelect+' top '+ CAST(@lastcount as VARCHAR(4))+' '+ @fldName+' from '+@tblName 131
+' order by '+ @fldSort +' '+ @strSortType+') AS TempTB'+' order by '+ @fldSort +' '+ @strFSortType 132
else 133
if @Sort=1 134
begin 135
set @strTmp=@SqlSelect+' * from ('+@SqlSelect+' top '+ CAST(@pageSize as VARCHAR(4))+' '+ @fldName+' from '+@tblName 136
+' where '+@ID+' >(select max('+ @ID +') from('+ @SqlSelect+' top '+ CAST(@pageSize*(@page-2)+@lastcount as Varchar(20)) +' '+ @ID +' from '+@tblName 137
+' order by '+ @fldSort +' '+ @strSortType+') AS TBMaxID)' 138
+' order by '+ @fldSort +' '+ @strSortType+') AS TempTB'+' order by '+ @fldSort +' '+ @strFSortType 139
end 140
else 141
begin 142
set @strTmp=@SqlSelect+' * from ('+@SqlSelect+' top '+ CAST(@pageSize as VARCHAR(4))+' '+ @fldName+' from '+@tblName 143
+' where '+@ID+' <(select min('+ @ID +') from('+ @SqlSelect+' top '+ CAST(@pageSize*(@page-2)+@lastcount as Varchar(20)) +' '+ @ID +' from '+@tblName 144
+' order by '+ @fldSort +' '+ @strSortType+') AS TBMaxID)' 145
+' order by '+ @fldSort +' '+ @strSortType+') AS TempTB'+' order by '+ @fldSort +' '+ @strFSortType 146
end 147
end 148
end 149

150
else --有查询条件 151
begin 152
if @pageIndex<2 or @page<=@pageIndex / 2 + @pageIndex % 2 --前半部分数据处理 153
begin 154
if @page=1 155
set @strTmp=@SqlSelect+' top '+ CAST(@pageSize as VARCHAR(4))+' '+ @fldName+' from '+@tblName 156
+' where 1=1 ' + @strCondition + ' order by '+ @fldSort +' '+ @strFSortType 157
else if(@Sort=1) 158
begin 159
set @strTmp=@SqlSelect+' top '+ CAST(@pageSize as VARCHAR(4))+' '+ @fldName+' from '+@tblName 160
+' where '+@ID+' <(select min('+ @ID +') from ('+ @SqlSelect+' top '+ CAST(@pageSize*(@page-1) as Varchar(20)) +' '+ @ID +' from '+@tblName 161
+' where (1=1) ' + @strCondition +' order by '+ @fldSort +' '+ @strFSortType+') AS TBMinID)' 162
+' '+ @strCondition +' order by '+ @fldSort +' '+ @strFSortType 163
end 164
else 165
begin 166
set @strTmp=@SqlSelect+' top '+ CAST(@pageSize as VARCHAR(4))+' '+ @fldName+' from '+@tblName 167
+' where '+@ID+' >(select max('+ @ID +') from ('+ @SqlSelect+' top '+ CAST(@pageSize*(@page-1) as Varchar(20)) +' '+ @ID +' from '+@tblName 168
+' where (1=1) ' + @strCondition +' order by '+ @fldSort +' '+ @strFSortType+') AS TBMinID)' 169
+' '+ @strCondition +' order by '+ @fldSort +' '+ @strFSortType 170
end 171
end 172
else 173
begin 174
set @page = @pageIndex-@page+1 --后半部分数据处理 175
if @page <= 1 --最后一页数据显示 176
set @strTmp=@SqlSelect+' * from ('+@SqlSelect+' top '+ CAST(@lastcount as VARCHAR(4))+' '+ @fldName+' from '+@tblName 177
+' where (1=1) '+ @strCondition +' order by '+ @fldSort +' '+ @strSortType+') AS TempTB'+' order by '+ @fldSort +' '+ @strFSortType 178
else if(@Sort=1) 179
set @strTmp=@SqlSelect+' * from ('+@SqlSelect+' top '+ CAST(@pageSize as VARCHAR(4))+' '+ @fldName+' from '+@tblName 180
+' where '+@ID+' >(select max('+ @ID +') from('+ @SqlSelect+' top '+ CAST(@pageSize*(@page-2)+@lastcount as Varchar(20)) +' '+ @ID +' from '+@tblName 181
+' where (1=1) '+ @strCondition +' order by '+ @fldSort +' '+ @strSortType+') AS TBMaxID)' 182
+' '+ @strCondition+' order by '+ @fldSort +' '+ @strSortType+') AS TempTB'+' order by '+ @fldSort +' '+ @strFSortType 183
else 184
set @strTmp=@SqlSelect+' * from ('+@SqlSelect+' top '+ CAST(@pageSize as VARCHAR(4))+' '+ @fldName+' from '+@tblName 185
+' where '+@ID+' <(select min('+ @ID +') from('+ @SqlSelect+' top '+ CAST(@pageSize*(@page-2)+@lastcount as Varchar(20)) +' '+ @ID +' from '+@tblName 186
+' where (1=1) '+ @strCondition +' order by '+ @fldSort +' '+ @strSortType+') AS TBMaxID)' 187
+' '+ @strCondition+' order by '+ @fldSort +' '+ @strSortType+') AS TempTB'+' order by '+ @fldSort +' '+ @strFSortType 188
end 189
end 190

191
------返回查询结果----- 192
exec sp_executesql @strTmp 193
select datediff(ms,@timediff,getdate()) as 耗时 194
--print @strTmp 195
SET NOCOUNT OFF 196
GO197

执行示例:exec proc_paged_2part_selectMax 'tb_testTable','ID,userName,userPWD,userEmail',10,100000,'ID',0,null,'ID',0
这种测试只在单机进行,并且没有在实际开发WEB项目中分页测试,测试项也比较单一,所以不够全面系统,但从其效率相比上,我们可以在数据库分页算法上进行有效的控制。
FeedBack:
http://bbs.21mmo.com/
你可以访问下看看
我也做过类似的测试,感觉你的
4临时表 780ms 796ms 798ms 780ms
测试结果有点奇怪,为什么不管翻到哪一页,需要的时间都差不多呢?
我的测试结果是前面快,后面慢的。
-----------------------------------------------
隆重发布.net项目开发工具(V3.0 ):
http://www.cnblogs.com/mrhgw/archive/2008/08/06/1261664.html
http://www.mrhgw.cn/
不知2008 能否出现比较完美的方法;
sqlsever 2000 方式的top max 啥的必须有数字型id才可以分页;
这在某些时候其实是一种对于方式,比如有些表就是guid 主键的
还要为表建立个没啥用的数字键;
2005 虽然可以 ROW_NUMBER() Over(...)
但是必须 over 是个很不太方便的方式,虽然有方法可以解决必须数字pk 的方法,不过还是恶心点;
如果能提供一个不要 over 仍然可以分页的方法就好了;
如果提供一套专门底层封装的分页函数就好了;
其实最主要的是 还有子查询不能排序,分组什么的才是最大问题;
标准行号,子查询排序分组;很多数据库都有的功能,不知sqlserver 何年何月
才能提供;
select * from (select *,Row_number() over(order by ID asc) as IDRank from tb_testTable) as IDWithRowNumber where IDRank>@pageSize*@pageIndex and IDRank<@pageSize*(@pageIndex+1)
你的上面这段代码会一次从数据库中取出所有的数据,这样操作的数据量会很大,现在你的SQL是在聚集索引中执行的时候你根本看不到这种差别,一旦你是在非聚集索引中执行上述代码的时候你的查询就会非常非常慢,正确的做法应该是先取出ID,再根据主键来查数据,就像下面这样。
select a.*
from tb_testTable as a
inner join ((select ID,Row_number() over(order by ID asc) as IDRank
from tb_testTable) as IDWithRowNumber
where IDRank>@pageSize*@pageIndex and IDRank<@pageSize*(@pageIndex+1)) as b
ON a.ID = a.ID
order by b.IDRank
其次使用Max的方式是比较快,但是如果你是在数据不唯一的字段上排序的话可能会因为数据的重复导致这种排序不可用。
这点可以通过查看执行计划和执行统计信息就可以看出来,尤其是在使用非聚集索引的时候差别非常明显。
有什么解决方法
1 2 3 4 5 6 7 8 9 10 | declare @pageCount intdeclare @counts intdeclare @pageSize intdeclare @currPage intset @pageSize = 100set @currPage = 2exec Proc_Paging 'pageTest','*',@pageSize,@currPage,'id',0,' col02 like '0%' ','id',0,@pageCount output,@counts outputselect @pageCount as pageCount,@counts as counts |

浙公网安备 33010602011771号
SELECT spaceid,spacetitle FROM
(select A.[spaceid], A.[spacetitle],
ROW_NUMBER() Over(order by A.Blog_BlogWeights DESC, A.createdatetime DESC) as rowNum
from tb_spaceconfigs A ) selectview
where rowNum between 140245 and 140248
在我这边,查询分析器已经需要8秒才会有结果出来,不知为何