几种Sql查询分页的写法

1.创建测试环境,(插入100万条数据大概耗时5分钟)。

create database DBTest

use DBTest

--创建测试表

create table pagetest

(

id int identity(1,1) not null,

col01 int null,

col02 nvarchar(50) null,

col03 datetime null

)

--1万记录集

declare @i int

set @i=0

while(@i<10000)

begin

insert into pagetest select cast(floor(rand()*10000) as int),left(newid(),10),getdate()

set @i=@i+1

end

 

2.几种典型的分页sql,下面例子是每页50条,198*50=9900,取第199页数据。

--写法1,not in/top

select top 50 * from pagetest

where id not in (select top 9900 id from pagetest order by id)

order by id

--写法2,not exists

select top 50 * from pagetest

where not exists

(select 1 from (select top 9900 id from pagetest order by id)a where a.id=pagetest.id)

order by id

--写法3,max/top

select top 50 * from pagetest

where id>(select max(id) from (select top 9900 id from pagetest order by id)a)

order by id

--写法4,row_number()

select top 50 * from

(select row_number()over(order by id)rownumber,* from pagetest)a

where rownumber>9900

select * from

(select row_number()over(order by id)rownumber,* from pagetest)a

where rownumber>9900 and rownumber<9951

select * from

(select row_number()over(order by id)rownumber,* from pagetest)a

where rownumber between 9901 and 9950

--写法5,在csdn上一帖子看到的,row_number() 变体,不基于已有字段产生记录序号,先按条件筛选以及排好序,再在结果集上给一常量列用于产生记录序号

select *

from (

select row_number()over(order by tempColumn)rownumber,*

from (select top 9950 tempColumn=0,* from pagetest where 1=1 order by id)a

)b

where rownumber>9900

3.分别在1万,10万(取1990页),100(取19900页)记录集下测试。

测试sql:

declare @begin_date datetime

declare @end_date datetime

select @begin_date = getdate()

<.....YOUR CODE.....>

select @end_date = getdate()

select datediff(ms,@begin_date,@end_date) as '毫秒'

 

1万:基本感觉不到差异。

10万:

4.结论:

1.max/top,ROW_NUMBER()都是比较不错的分页方法。相比ROW_NUMBER()只支持sql2005及以上版本,max/top有更好的可移植性,能同时适用于sql2000,access。

2.not exists感觉是要比not in效率高一点点。

3.ROW_NUMBER()的3种不同写法效率看起来差不多。

4.ROW_NUMBER() 的变体基于我这个测试效率实在不好。原帖在这里 http://topic.csdn.net/u/20100617/04/80d1bd99-2e1c-4083-ad87-72bf706cb536.html

 

PS.上面的分页排序都是基于自增字段id。测试环境还提供了int,nvarchar,datetime类型字段,也可以试试。不过对于非主键没索引的大数据量排序效率应该是很不理想的。

 

5.简单将ROWNUMBER,max/top的方式封装到存储过程。

ROWNUMBER():

1 ALTER PROCEDURE [dbo].[Proc_SqlPageByRownumber]

2 (

3 @tbName VARCHAR(255), --表名

4 @tbGetFields VARCHAR(1000)= '*',--返回字段

5 @OrderfldName VARCHAR(255), --排序的字段名

6 @PageSize INT=20, --页尺寸

7 @PageIndex INT=1, --页码

8 @OrderType bit = 0, --0升序,非0降序

9 @strWhere VARCHAR(1000)='', --查询条件

10 --@TotalCount INT OUTPUT --返回总记录数

11 )

12 AS

13 -- =============================================

14 -- Author: allen (liyuxin)

15 -- Create date: 2012-03-30

16 -- Description: 分页存储过程(支持多表连接查询)

17 -- Modify [1]: 2012-03-30

18 -- =============================================

19 BEGIN

20 DECLARE @strSql VARCHAR(5000) --主语句

21 DECLARE @strSqlCount NVARCHAR(500)--查询记录总数主语句

22 DECLARE @strOrder VARCHAR(300) -- 排序类型

23

24 --------------总记录数---------------

25 IF ISNULL(@strWhere,'') <>''

26 SET @strSqlCount='Select @TotalCout=count(*) from ' + @tbName + ' where 1=1 '+ @strWhere

27 ELSE SET @strSqlCount='Select @TotalCout=count(*) from ' + @tbName

28

29 --exec sp_executesql @strSqlCount,N'@TotalCout int output',@TotalCount output

30 --------------分页------------

31 IF @PageIndex <= 0 SET @PageIndex = 1

32

33 IF(@OrderType<>0) SET @strOrder=' ORDER BY '+@OrderfldName+' DESC '

34 ELSE SET @strOrder=' ORDER BY '+@OrderfldName+' ASC '

35

36 SET @strSql='SELECT * FROM

37 (SELECT ROW_NUMBER() OVER('+@strOrder+') RowNo,'+ @tbGetFields+' FROM ' + @tbName + ' WHERE 1=1 ' + @strWhere+' ) tb

38 WHERE tb.RowNo BETWEEN '+str((@PageIndex-1)*@PageSize+1)+' AND ' +str(@PageIndex*@PageSize)

39

40 exec(@strSql)

41 SELECT @TotalCount

42 END

注意:多表连接时需注意的地方

1.必填项:tbName,OrderfldName,tbGetFields

2.实例:tbName =“UserInfo u INNER JOIN Department d ON u.DepID=d.ID”

        tbGetFields=“u.ID AS UserID,u.Name,u.Sex,d.ID AS DepID,d.DefName”

        OrderfldName=“u.ID,ASC|u.Name,DESC” (格式:Name,ASC|ID,DESC)

        strWhere:每个条件前必须添加 AND (例如:AND UserInfo.DepID=1 )

 

Max/top:(简单写了下,需要满足主键字段名称就是"id")

create proc [dbo].[spSqlPageByMaxTop]

@tbName varchar(255), --表名

@tbFields varchar(1000), --返回字段

@PageSize int, --页尺寸

@PageIndex int, --页码

@strWhere varchar(1000), --查询条件

@StrOrder varchar(255), --排序条件

@Total int output --返回总记录数

as

declare @strSql varchar(5000) --主语句

declare @strSqlCount nvarchar(500)--查询记录总数主语句

--------------总记录数---------------

if @strWhere !=''

begin

set @strSqlCount='Select @TotalCout=count(*) from ' + @tbName + ' where '+ @strWhere

end

else

begin

set @strSqlCount='Select @TotalCout=count(*) from ' + @tbName

end

--------------分页------------

if @PageIndex <= 0

begin

set @PageIndex = 1

end

set @strSql='select top '+str(@PageSize)+' * from ' + @tbName + '

where id>(select max(id) from (select top '+str((@PageIndex-1)*@PageSize)+' id from ' + @tbName + ''+@strOrder+')a)

'+@strOrder+''

exec sp_executesql @strSqlCount,N'@TotalCout int output',@Total output

exec(@strSql)

园子里搜到Max/top这么一个版本,看起来很强大,http://www.cnblogs.com/hertcloud/archive/2005/12/21/301327.html

调用:

declare @count int

--exec [dbo].[spSqlPageByRownumber]'pagetest','*',50,20,'','order by id asc',@count output

exec [dbo].[spSqlPageByMaxTop]'pagetest','*',50,20,'','order by id asc',@count output

select @count

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转载自blog.csdn.net/QL753123/article/details/71051484