• 高效的SQLSERVER分页查询(推荐)


    Sqlserver数据库分页查询一直是Sqlserver的短板,闲来无事,想出几种方法,假设有表ARTICLE,字段ID、YEAR...(其他省略),数据53210条(客户真实数据,量不大),分页查询每页30条,查询第1500页(即第45001-45030条数据),字段ID聚集索引,YEAR无索引,Sqlserver版本:2008R2
     
     

    第一种方案、最简单、普通的方法:

    代码如下:
    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

         平均查询100次所需时间:45s

    第二种方案:

    代码如下:

    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 

         平均查询100次所需时间:138S

    第三种方案:

    代码如下:

    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

         平均查询100次所需时间:21S

    第四种方案:

    代码如下:
    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

         平均查询100次所需时间:20S

    第五种方案:

    代码如下:

    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 

         平均查询100次所需时间:15S

    查询第1000-1030条记录

    第一种方案:

    代码如下:

    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 

         平均查询100次所需时间:80s

    第二种方案:

    代码如下:

    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 

         平均查询100次所需时间:30S

    第三种方案:

    代码如下:
    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

         平均查询100次所需时间:12S

    第四种方案:

    代码如下:
    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

         平均查询100次所需时间:13S

    第五种方案:

    代码如下:

    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 

         平均查询100次所需时间:14S

         由此可见在查询页数靠前时,效率3>4>5>2>1,页码靠后时5>4>3>1>2,再根据用户习惯,一般用户的检索只看最前面几页,因此选择3 4 5方案均可,若综合考虑方案5是最好的选择,但是要注意SQL2000不支持row_number()函数,由于时间和条件的限制没有做更深入、范围更广的测试,有兴趣的可以仔细研究下。

    以下是根据第四种方案编写的一个分页存储过程:

    代码如下:
    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,    --总页数输出
    @RCount int output,    --总记录数输出
    @sys_Table nvarchar(100),    --查询表名
    @sys_Key varchar(50),        --主键
    @sys_Fields nvarchar(500),    --查询字段
    @sys_Where nvarchar(3000),    --查询条件
    @sys_Order nvarchar(100),    --排序字段
    @sys_Begin int,        --开始位置
    @sys_PageIndex int,        --当前页数
    @sys_PageSize int        --页大小
    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 @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


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  • 原文地址:https://www.cnblogs.com/firstdream/p/6392872.html
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