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高效的SQLSERVER分頁查詢(推薦)_Mssql數(shù)據(jù)庫教程

編輯Tag賺U幣

推薦:SQL Server2012在開發(fā)中的一些新特性
SQL Server 2012已經(jīng)發(fā)布一段時間了,最近在新的機器上安裝了最新的SQL Server 2012 SP1,體檢下感覺良好。官方給出了一大堆SQL2012相對于SQL2008R2的新特性,但是大多數(shù)對于普通開發(fā)人員來說都是浮云,根本用不到,下面就說說一些對于開發(fā)人員來說比較有用的新特性。

第一種方案、最簡單、普通的方法:

復制代碼 代碼如下:www.hl5o.cn

SELECT TOP 30 * FROM ARTICLE WHERE ID NOT IN(SELECT TOP 45000 ID FROM ARTICLE ORDER BY YEAR DESC, ID DESC) ORDER BY YEAR DESC,ID DESC

平均查詢100次所需時間:45s

第二種方案:

復制代碼 代碼如下:www.hl5o.cn

SELECT * FROM (  SELECT TOP 30 * FROM (SELECT TOP 45030 * FROM ARTICLE ORDER BY YEAR DESC, ID DESC) f ORDER BY f.YEAR ASC, f.ID DESC) s ORDER BY s.YEAR DESC,s.ID DESC

平均查詢100次所需時間:138S

第三種方案:

復制代碼 代碼如下:www.hl5o.cn

SELECT * FROM ARTICLE w1,
(
SELECT TOP 30 ID FROM
(
SELECT TOP 50030 ID, YEAR FROM ARTICLE ORDER BY YEAR DESC, ID DESC
) w ORDER BY w.YEAR ASC, w.ID ASC
) w2 WHERE w1.ID = w2.ID ORDER BY w1.YEAR DESC, w1.ID DESC

平均查詢100次所需時間:21S

第四種方案:

復制代碼 代碼如下:www.hl5o.cn

SELECT * FROM ARTICLE w1
WHERE ID in
(
SELECT top 30 ID FROM
(
SELECT top 45030 ID, YEAR FROM ARTICLE ORDER BY YEAR DESC, ID DESC
) w ORDER BY w.YEAR ASC, w.ID ASC
)
ORDER BY w1.YEAR DESC, w1.ID DESC

平均查詢100次所需時間:20S

第五種方案:

復制代碼 代碼如下:www.hl5o.cn

SELECT w2.n, w1.* FROM ARTICLE w1, (  SELECT TOP 50030 row_number() OVER (ORDER BY YEAR DESC, ID DESC) n, ID FROM ARTICLE ) w2 WHERE w1.ID = w2.ID AND w2.n > 50000 ORDER BY w2.n ASC

平均查詢100次所需時間:15S

查詢第1000-1030條記錄

第一種方案:

復制代碼 代碼如下:www.hl5o.cn

SELECT TOP 30 * FROM ARTICLE WHERE ID NOT IN(SELECT TOP 1000 ID FROM ARTICLE ORDER BY YEAR DESC, ID DESC) ORDER BY YEAR DESC,ID DESC

平均查詢100次所需時間:80s

第二種方案:

復制代碼 代碼如下:www.hl5o.cn

SELECT * FROM (   SELECT TOP 30 * FROM (SELECT TOP 1030 * FROM ARTICLE ORDER BY YEAR DESC, ID DESC) f ORDER BY f.YEAR ASC, f.ID DESC) s ORDER BY s.YEAR DESC,s.ID DESC

平均查詢100次所需時間:30S

第三種方案:

復制代碼 代碼如下:www.hl5o.cn

SELECT * FROM ARTICLE w1,
(
SELECT TOP 30 ID FROM
(
SELECT TOP 1030 ID, YEAR FROM ARTICLE ORDER BY YEAR DESC, ID DESC
) w ORDER BY w.YEAR ASC, w.ID ASC
) w2 WHERE w1.ID = w2.ID ORDER BY w1.YEAR DESC, w1.ID DESC

平均查詢100次所需時間:12S

第四種方案:

復制代碼 代碼如下:www.hl5o.cn

SELECT * FROM ARTICLE w1
WHERE ID in
(
SELECT top 30 ID FROM
(
SELECT top 1030 ID, YEAR FROM ARTICLE ORDER BY YEAR DESC, ID DESC
) w ORDER BY w.YEAR ASC, w.ID ASC
)
ORDER BY w1.YEAR DESC, w1.ID DESC

平均查詢100次所需時間:13S

第五種方案:

復制代碼 代碼如下:www.hl5o.cn

SELECT w2.n, w1.* FROM ARTICLE w1,(   SELECT TOP 1030 row_number() OVER (ORDER BY YEAR DESC, ID DESC) n, ID FROM ARTICLE) w2 WHERE w1.ID = w2.ID AND w2.n > 1000 ORDER BY w2.n ASC

平均查詢100次所需時間:14S

由此可見在查詢頁數(shù)靠前時,效率3>4>5>2>1,頁碼靠后時5>4>3>1>2,再根據(jù)用戶習慣,一般用戶的檢索只看最前面幾頁,因此選擇3 4 5方案均可,若綜合考慮方案5是最好的選擇,但是要注意SQL2000不支持row_number()函數(shù),由于時間和條件的限制沒有做更深入、范圍更廣的測試,有興趣的可以仔細研究下。

以下是根據(jù)第四種方案編寫的一個分頁存儲過程:

復制代碼 代碼如下:www.hl5o.cn

if exists (select * from dbo.sysobjects where id = object_id(N'[dbo].[sys_Page_v2]') and OBJECTPROPERTY(id, N'IsProcedure') = 1)
drop procedure [dbo].[sys_Page_v2]
GO

CREATE PROCEDURE [dbo].[sys_Page_v2]
@PCount int output, --總頁數(shù)輸出
@RCount int output, --總記錄數(shù)輸出
@sys_Table nvarchar(100), --查詢表名
@sys_Key varchar(50), --主鍵
@sys_Fields nvarchar(500), --查詢字段
@sys_Where nvarchar(3000), --查詢條件
@sys_Order nvarchar(100), --排序字段
@sys_Begin int, --開始位置
@sys_PageIndex int, --當前頁數(shù)
@sys_PageSize int --頁大小
AS

SET NOCOUNT ON
SET ANSI_WARNINGS ON

IF @sys_PageSize < 0 OR @sys_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(@sys_Begin <=0)
set @sys_Begin=0
else
set @sys_Begin=@sys_Begin-1

IF ISNULL(@sys_Where,'') = ''
SET @new_where1 = ' '
ELSE
SET @new_where1 = ' WHERE ' + @sys_Where

IF ISNULL(@sys_Order,'') <> ''
BEGIN
SET @new_order1 = ' ORDER BY ' + Replace(@sys_Order,'desc','')
SET @new_order1 = Replace(@new_order1,'asc','desc')

SET @new_order2 = ' ORDER BY ' + @sys_Order
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(@sys_PageSize AS NVARCHAR)+') FROM ' + @sys_Table + @new_where1

EXEC SP_EXECUTESQL @SqlCount,N'@RCount INT OUTPUT,@PCount INT OUTPUT',
@RCount OUTPUT,@PCount OUTPUT

IF @sys_PageIndex > CEILING((@RCount+0.0)/@sys_PageSize) --如果輸入的當前頁數(shù)大于實際總頁數(shù),則把實際總頁數(shù)賦值給當前頁數(shù)
BEGIN
SET @sys_PageIndex = CEILING((@RCount+0.0)/@sys_PageSize)
END

set @sql = 'select '+ @sys_fields +' from ' + @sys_Table + ' w1 '
+ ' where '+ @sys_Key +' in ('
+'select top '+ ltrim(str(@sys_PageSize)) +' ' + @sys_Key + ' from '
+'('
+'select top ' + ltrim(STR(@sys_PageSize * @sys_PageIndex + @sys_Begin)) + ' ' + @sys_Key + ' FROM '
+ @sys_Table + @new_where1 + @new_order2
+') w ' + @new_order1
+') ' + @new_order2

print(@sql)

Exec(@sql)

GO

分享:sql where 1=1的優(yōu)缺點分析
where 1=1; 這個條件始終為True,在不定數(shù)量查詢條件情況下,1=1可以很方便的規(guī)范語句

來源:模板無憂//所屬分類:Mssql數(shù)據(jù)庫教程/更新時間:2013-04-23
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