分页存储过程效率对比
1. 随便找了个网上效率被认为比较高的分页过程
if exists (select * from dbo.sysobjects where id = object_id(N'[dbo].[xp_getpager_user_dt]') and OBJECTPROPERTY(id, N'IsProcedure') = 1)
drop procedure [dbo].[xp_getpager_user_dt]
GO
CREATE PROCEDURE [dbo].[xp_getpager_user_dt]
@pcount int output, --总页数输出
@rcount int output, --总记录数输出
@tablename nvarchar(100), --查询表名
@keys varchar(50), --主键
@fields nvarchar(500), --查询字段
@where nvarchar(3000), --查询条件
@sortfields nvarchar(100), --排序字段
@beginindex int=0, --开始位置
@pageindex int=1, --当前页数
@pagesize int=100 --页大小
AS
SET NOCOUNT ON
SET ANSI_WARNINGS ON
IF @pagesize < 0 OR @pageindex < 0
BEGIN
RETURN
END
DECLARE @new_where1 NVARCHAR(3000)
DECLARE @new_order1 NVARCHAR(100)
DECLARE @new_order2 NVARCHAR(100)
DECLARE @Sql NVARCHAR(4000)
DECLARE @SqlCount NVARCHAR(4000)
DECLARE @Top int
if(@beginindex <=0)
set @beginindex=0
else
set @beginindex=@beginindex-1
IF ISNULL(@where,'') = ''
SET @new_where1 = ' '
ELSE
SET @new_where1 = ' WHERE ' + @where
IF ISNULL(@sortfields,'') <> ''
BEGIN
SET @new_order1 = ' ORDER BY ' + Replace(@sortfields,'desc','')
SET @new_order1 = Replace(@new_order1,'asc','desc')
SET @new_order2 = ' ORDER BY ' + @sortfields
END
ELSE
BEGIN
SET @new_order1 = ' ORDER BY ID DESC'
SET @new_order2 = ' ORDER BY ID ASC'
END
SET @SqlCount = 'SELECT @rcount=COUNT(1),@pcount=CEILING((COUNT(1)+0.0)/'
+ CAST(@pagesize AS NVARCHAR)+') FROM ' + @tablename + @new_where1
EXEC SP_EXECUTESQL @SqlCount,N'@rcount INT OUTPUT,@pcount INT OUTPUT',
@rcount OUTPUT,@pcount OUTPUT
IF @pageindex > CEILING((@rcount+0.0)/@pagesize) --如果输入的当前页数大于实际总页数,则把实际总页数赋值给当前页数
BEGIN
SET @pageindex = CEILING((@rcount+0.0)/@pagesize)
END
set @sql = 'select '+ @fields +' from ' + @tablename + ' w1 '
+ ' where '+ @keys +' in ('
+'select top '+ ltrim(str(@pagesize)) +' ' + @keys + ' from '
+'('
+'select top ' + ltrim(STR(@pagesize * @pageindex + @beginindex)) + ' ' + @keys + ' FROM '
+ @tablename + @new_where1 + @new_order2
+') w ' + @new_order1
+') ' + @new_order2
print(@sql)
Exec(@sql)
GO
2. 优化后的分页过程
create PROC [dbo].[xp_GetPager_user_dt2]
@quitdate nvarchar(10)='2015-01-01',
@userno nvarchar(10)='',
@sortfields nvarchar(100)='',
@pageindex int=1,
@pagesize int=5
AS
begin
--构建执行脚本
declare @sql nvarchar(1800)='',
--存储对象
@tablename NVARCHAR(50)=' v_pn_users_fromlocal',
--返回字段
@returnfields nvarchar(1000)='',
--where 条件
@where nvarchar(200)=' where 1=1 ',--and abs([Status]) >= 10 and [Status] <> 40 and isvalid<>-1 ,
--上次查询数量
@lastcount int =-1
--计算前面查询的数据总数
set @lastcount=(@pageindex-1)*@pagesize
if @lastcount<0 set @lastcount=0
--判断排序字段
if @sortfields=''
set @sortfields='quitdate'
--*******************************************返回字段设定*****************************************
set @returnfields='code,name,fname,email,isvalid,hiredate,hirevalid,quitdate,costcenter,sex,IDCard,PassDate '
--*******************************************由条件构建Where***************************************
if @quitdate<>'2015-01-01'
set @where+=' and quitdate > '''+@quitdate+''''
if @userno<>''
set @where+=' and code = '''+@userno+''''
--*******************************************由条件构建SQL***************************************
set @sql='
declare @lastmaxid int=0,@total int
--缓存的临时表，并创建检索rowID
if object_id(''tempdb..#t'') is not null
drop table #t
select row_number() over (order by '+@sortfields+') rowid, * into #t from '+@tablename
set @sql += @where
--获取按照执行排序，前面查询的数据的最大ID
set @sql +=' select top '+cast(@lastcount as nvarchar)+' @lastmaxid=max(rowid) from #t'
set @sql+= ' group by rowid'
--获取符合条件的数据总数
set @sql+=' select @total=count(*) from #t'
--**********************************************构造执行返回结果的SQL*****************************************
set @sql+=' select '
if @pagesize>0
set @sql+='top '+cast(@pagesize as nvarchar)
set @sql+=' rowid '
if @returnfields<>''
begin
set @sql+=','+@returnfields
end
set @sql+=' from #t
where rowid>@lastmaxid order by rowid'
set @sql+=' select @total total,'+cast(@pagesize as nvarchar)+' pagesize,'+cast(@pageindex as nvarchar)+' pageindex'
set @sql+=' if object_id(''tempdb..#t'') is not null
drop table #t'
exec(@sql)
END
效率对比
1. declare @pcount int,@rcount int
exec [dbo].[xp_getpager_user_dt]
@pcount output, --总页数输出
@rcount output, --总记录数输出
@tablename ='v_pn_users_fromlocal', --查询表名
@keys ='code', --主键
@fields ='code,name,fname,email,isvalid,hiredate,hirevalid,quitdate,costcenter,sex,IDCard,PassDate', --查询字段
@where ='quitdate>''2015-01-01''', --查询条件
@sortfields ='quitdate', --排序字段
@beginindex =0, --开始位置
@pageindex =1, --当前页数
@pagesize =100
执行时间：1 min 18s
2. [xp_GetPager_user_dt2] @quitdate='2015-01-01',@pagesize=100
执行时间：<1s
