• 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
    GO
    use data_Test
    GO
    create table tb_TestTable   --创建表
    (
    id int identity(1,1) primary key,
    userName nvarchar(20) not null,
    userPWD nvarchar(20) not null,
    userEmail nvarchar(40) null
    )
    GO

    然后我们在数据表中插入2000000条数据:
     
    --插入数据
    set identity_insert tb_TestTable on
    declare @count int
    set @count=1
    while @count<=2000000
    begin
    insert into tb_TestTable(id,userName,userPWD,userEmail) values
    (@count,'admin','admin888','lli0077@yahoo.com.cn')
    set @count=@count+1
    end
    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
    (
    @pageIndex int,  --页索引
        @pageSize int    --每页记录数
    )
    as
    begin
    set nocount on;
    declare @timediff datetime --耗时
        declare @sql nvarchar(500)
    select @timediff=Getdate()
    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'
    execute(@sql)  --因select top后不支技直接接参数,所以写成了字符串@sql
        select datediff(ms,@timediff,GetDate()) as 耗时
    set nocount off;
    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)
    (
    @pageIndex int,  --页索引
        @pageSize int    --页记录数
    )
    as
    begin
    set nocount on;
    declare @timediff datetime
    declare @sql nvarchar(500)
    select @timediff=Getdate()
    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'
    execute(@sql)
    select datediff(ms,@timediff,GetDate()) as 耗时
    set nocount off;
    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
    (
    @pageIndex int,
    @pageSize int
    )
    as
    declare @count int
    declare @ID int
    declare @timediff datetime
    declare @sql nvarchar(500)
    begin
    set nocount on;
    select @count=0,@ID=0,@timediff=getdate()
    select @count=@count+1,@ID=case when @count<=@pageSize*@pageIndex then ID else @ID end from tb_testTable order by id
    set @sql='select top '+str(@pageSize)+' * from tb_testTable where ID>'+str(@ID)
    execute(@sql)
    select datediff(ms,@timediff,getdate()) as 耗时
    set nocount off;
    end

    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()
    (
    @pageIndex int,
    @pageSize int
    )
    as
    declare @timediff datetime
    begin
    set nocount on;
    select @timediff=getdate()
    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)
    select datediff(ms,@timediff,getdate()) as 耗时
    set nocount off;
    end

    5,利用临时表及Row_number
    create procedure proc_CTE  --利用临时表及Row_number
    (
    @pageIndex int,  --页索引
        @pageSize int    --页记录数
    )
    as
    set nocount on;
    declare @ctestr nvarchar(400)
    declare @strSql nvarchar(400)
    declare @datediff datetime
    begin
    select @datediff=GetDate()
    set @ctestr='with Table_CTE as
    (select ceiling((Row_number() over(order by ID ASC))/'+str(@pageSize)+') as page_num,* from tb_TestTable)';
    set @strSql=@ctestr+' select * From Table_CTE where page_num='+str(@pageIndex)
    end
    begin
    execute sp_executesql @strSql
    select datediff(ms,@datediff,GetDate())
    set nocount off;
    end

    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 第10000页 第100000页 第199999页 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
    5临时表 780ms 796ms 798ms 780ms 805ms 4


    测试结果显示:

    输出窗口 复制  保存
    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:
    存过 第2页耗时 第1000页 第10000页 第100000页 第199999页 效率排行
    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 -------*/
    --/*-----存储过程 分页处理 浪尘 2008-9-1修改----------*/
    --/*----- 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 -------*/
    
    alter PROCEDURE proc_paged_2part_selectMax
    (
    @tblName     nvarchar(200),        ----要显示的表或多个表的连接
    @fldName     nvarchar(500) = '*',    ----要显示的字段列表
    @pageSize    int = 10,        ----每页显示的记录个数
    @page        int = 1,        ----要显示那一页的记录
    @fldSort    nvarchar(200) = null,    ----排序字段列表或条件
    @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 ')
    @strCondition    nvarchar(1000) = null,    ----查询条件,不需where
    @ID        nvarchar(150),        ----主表的主键
    @Dist                 bit = 0,           ----是否添加查询字段的 DISTINCT 默认0不添加/1添加
    @pageCount    int = 1 output,            ----查询结果分页后的总页数
    @Counts    int = 1 output                ----查询到的记录数
    )
    AS
    SET NOCOUNT ON
    Declare @sqlTmp nvarchar(1000)        ----存放动态生成的SQL语句
    Declare @strTmp nvarchar(1000)        ----存放取得查询结果总数的查询语句
    Declare @strID     nvarchar(1000)        ----存放取得查询开头或结尾ID的查询语句
    
    Declare @strSortType nvarchar(10)    ----数据排序规则A
    Declare @strFSortType nvarchar(10)    ----数据排序规则B
    
    Declare @SqlSelect nvarchar(50)         ----对含有DISTINCT的查询进行SQL构造
    Declare @SqlCounts nvarchar(50)          ----对含有DISTINCT的总数查询进行SQL构造
    
    declare @timediff datetime  --耗时测试时间差
    select @timediff=getdate()
    if @Dist  = 0
    begin
    set @SqlSelect = 'select '
    set @SqlCounts = 'Count(*)'
    end
    else
    begin
    set @SqlSelect = 'select distinct '
    set @SqlCounts = 'Count(DISTINCT '+@ID+')'
    end
    if @Sort=0
    begin
    set @strFSortType=' ASC '
    set @strSortType=' DESC '
    end
    else
    begin
    set @strFSortType=' DESC '
    set @strSortType=' ASC '
    end
    --------生成查询语句--------
    --此处@strTmp为取得查询结果数量的语句
    if @strCondition is null or @strCondition=''     --没有设置显示条件
    begin
    set @sqlTmp =  @fldName + ' From ' + @tblName
    set @strTmp = @SqlSelect+' @Counts='+@SqlCounts+' FROM '+@tblName
    set @strID = ' From ' + @tblName
    end
    else
    begin
    set @sqlTmp = + @fldName + 'From ' + @tblName + ' where (1>0) ' + @strCondition
    set @strTmp = @SqlSelect+' @Counts='+@SqlCounts+' FROM '+@tblName + ' where (1>0) ' + @strCondition
    set @strID = ' From ' + @tblName + ' where (1>0) ' + @strCondition
    end
    ----取得查询结果总数量-----
    exec sp_executesql @strTmp,N'@Counts int out ',@Counts out
    declare @tmpCounts int
    if @Counts = 0
    set @tmpCounts = 1
    else
    set @tmpCounts = @Counts
    --取得分页总数
        set @pageCount=(@tmpCounts+@pageSize-1)/@pageSize
    /**当前页大于总页数 取最后一页**/
    if @page>@pageCount
    set @page=@pageCount
    --/*-----数据分页2分处理-------*/
        declare @pageIndex int --总数/页大小
        declare @lastcount int --总数%页大小
    
    set @pageIndex = @tmpCounts/@pageSize
    set @lastcount = @tmpCounts%@pageSize
    if @lastcount > 0
    set @pageIndex = @pageIndex + 1
    else
    set @lastcount = @pagesize
    --//***显示分页
        if @strCondition is null or @strCondition=''     --没有设置显示条件
        begin
    if @pageIndex<2 or @page<=@pageIndex / 2 + @pageIndex % 2   --前半部分数据处理
                begin
    if @page=1
    set @strTmp=@SqlSelect+' top '+ CAST(@pageSize as VARCHAR(4))+' '+ @fldName+' from '+@tblName
    +' order by '+ @fldSort +' '+ @strFSortType
    else
    begin
    if @Sort=1
    begin
    set @strTmp=@SqlSelect+' top '+ CAST(@pageSize as VARCHAR(4))+' '+ @fldName+' from '+@tblName
    +' where '+@ID+' <(select min('+ @ID +') from ('+ @SqlSelect+' top '+ CAST(@pageSize*(@page-1) as Varchar(20)) +' '+ @ID +' from '+@tblName
    +' order by '+ @fldSort +' '+ @strFSortType+') AS TBMinID)'
    +' order by '+ @fldSort +' '+ @strFSortType
    end
    else
    begin
    set @strTmp=@SqlSelect+' top '+ CAST(@pageSize as VARCHAR(4))+' '+ @fldName+' from '+@tblName
    +' where '+@ID+' >(select max('+ @ID +') from ('+ @SqlSelect+' top '+ CAST(@pageSize*(@page-1) as Varchar(20)) +' '+ @ID +' from '+@tblName
    +' order by '+ @fldSort +' '+ @strFSortType+') AS TBMinID)'
    +' order by '+ @fldSort +' '+ @strFSortType
    end
    end
    end
    else
    begin
    set @page = @pageIndex-@page+1 --后半部分数据处理
                    if @page <= 1 --最后一页数据显示
                        set @strTmp=@SqlSelect+' * from ('+@SqlSelect+' top '+ CAST(@lastcount as VARCHAR(4))+' '+ @fldName+' from '+@tblName
    +' order by '+ @fldSort +' '+ @strSortType+') AS TempTB'+' order by '+ @fldSort +' '+ @strFSortType
    else
    if @Sort=1
    begin
    set @strTmp=@SqlSelect+' * from ('+@SqlSelect+' top '+ CAST(@pageSize as VARCHAR(4))+' '+ @fldName+' from '+@tblName
    +' where '+@ID+' >(select max('+ @ID +') from('+ @SqlSelect+' top '+ CAST(@pageSize*(@page-2)+@lastcount as Varchar(20)) +' '+ @ID +' from '+@tblName
    +' order by '+ @fldSort +' '+ @strSortType+') AS TBMaxID)'
    +' order by '+ @fldSort +' '+ @strSortType+') AS TempTB'+' order by '+ @fldSort +' '+ @strFSortType
    end
    else
    begin
    set @strTmp=@SqlSelect+' * from ('+@SqlSelect+' top '+ CAST(@pageSize as VARCHAR(4))+' '+ @fldName+' from '+@tblName
    +' where '+@ID+' <(select min('+ @ID +') from('+ @SqlSelect+' top '+ CAST(@pageSize*(@page-2)+@lastcount as Varchar(20)) +' '+ @ID +' from '+@tblName
    +' order by '+ @fldSort +' '+ @strSortType+') AS TBMaxID)'
    +' order by '+ @fldSort +' '+ @strSortType+') AS TempTB'+' order by '+ @fldSort +' '+ @strFSortType
    end
    end
    end
    else --有查询条件
        begin
    if @pageIndex<2 or @page<=@pageIndex / 2 + @pageIndex % 2   --前半部分数据处理
            begin
    if @page=1
    set @strTmp=@SqlSelect+' top '+ CAST(@pageSize as VARCHAR(4))+' '+ @fldName+' from '+@tblName
    +' where 1=1 ' + @strCondition + ' order by '+ @fldSort +' '+ @strFSortType
    else if(@Sort=1)
    begin
    set @strTmp=@SqlSelect+' top '+ CAST(@pageSize as VARCHAR(4))+' '+ @fldName+' from '+@tblName
    +' where '+@ID+' <(select min('+ @ID +') from ('+ @SqlSelect+' top '+ CAST(@pageSize*(@page-1) as Varchar(20)) +' '+ @ID +' from '+@tblName
    +' where (1=1) ' + @strCondition +' order by '+ @fldSort +' '+ @strFSortType+') AS TBMinID)'
    +' '+ @strCondition +' order by '+ @fldSort +' '+ @strFSortType
    end
    else
    begin
    set @strTmp=@SqlSelect+' top '+ CAST(@pageSize as VARCHAR(4))+' '+ @fldName+' from '+@tblName
    +' where '+@ID+' >(select max('+ @ID +') from ('+ @SqlSelect+' top '+ CAST(@pageSize*(@page-1) as Varchar(20)) +' '+ @ID +' from '+@tblName
    +' where (1=1) ' + @strCondition +' order by '+ @fldSort +' '+ @strFSortType+') AS TBMinID)'
    +' '+ @strCondition +' order by '+ @fldSort +' '+ @strFSortType
    end
    end
    else
    begin
    set @page = @pageIndex-@page+1 --后半部分数据处理
                if @page <= 1 --最后一页数据显示
                        set @strTmp=@SqlSelect+' * from ('+@SqlSelect+' top '+ CAST(@lastcount as VARCHAR(4))+' '+ @fldName+' from '+@tblName
    +' where (1=1) '+ @strCondition +' order by '+ @fldSort +' '+ @strSortType+') AS TempTB'+' order by '+ @fldSort +' '+ @strFSortType
    else if(@Sort=1)
    set @strTmp=@SqlSelect+' * from ('+@SqlSelect+' top '+ CAST(@pageSize as VARCHAR(4))+' '+ @fldName+' from '+@tblName
    +' where '+@ID+' >(select max('+ @ID +') from('+ @SqlSelect+' top '+ CAST(@pageSize*(@page-2)+@lastcount as Varchar(20)) +' '+ @ID +' from '+@tblName
    +' where (1=1) '+ @strCondition +' order by '+ @fldSort +' '+ @strSortType+') AS TBMaxID)'
    +' '+ @strCondition+' order by '+ @fldSort +' '+ @strSortType+') AS TempTB'+' order by '+ @fldSort +' '+ @strFSortType
    else
    set @strTmp=@SqlSelect+' * from ('+@SqlSelect+' top '+ CAST(@pageSize as VARCHAR(4))+' '+ @fldName+' from '+@tblName
    +' where '+@ID+' <(select min('+ @ID +') from('+ @SqlSelect+' top '+ CAST(@pageSize*(@page-2)+@lastcount as Varchar(20)) +' '+ @ID +' from '+@tblName
    +' where (1=1) '+ @strCondition +' order by '+ @fldSort +' '+ @strSortType+') AS TBMaxID)'
    +' '+ @strCondition+' order by '+ @fldSort +' '+ @strSortType+') AS TempTB'+' order by '+ @fldSort +' '+ @strFSortType
    end
    end
    ------返回查询结果-----
    exec sp_executesql @strTmp
    select datediff(ms,@timediff,getdate()) as 耗时
    --print @strTmp
    SET NOCOUNT OFF
    GO


    执行示例:
     
    exec proc_paged_2part_selectMax 'tb_testTable','ID,userName,userPWD,userEmail',10,100000,'ID',0,null,'ID',0
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  • 原文地址:https://www.cnblogs.com/sdjxcolin/p/1368037.html
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