• 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 -------*/ 
    --/*-----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 
      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。

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  • 原文地址:https://www.cnblogs.com/computer/p/1780722.html
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