高效率的SQLSERVER分页查询的几种示例分析

高效的SQLSERVER分页查询的几种示例分析

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:

1 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:

1 SELECT * FROM (
2     SELECT TOP 30 * FROM (
3         SELECT TOP 45030 * FROM ARTICLE ORDER BY YEAR DESC, ID DESC
4     ) f ORDER BY f.YEAR ASC, f.ID DESC
5 ) 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:

1 SELECT * FROM ARTICLE w1, 
2 (
3     SELECT TOP 30 ID FROM 
4     (
5         SELECT TOP 50030 ID, YEAR FROM ARTICLE ORDER BY YEAR DESC, ID DESC
6     ) w ORDER BY w.YEAR ASC, w.ID ASC
7 ) 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:

1 SELECT * FROM ARTICLE w1 
2     WHERE ID in 
3         (
4             SELECT top 30 ID FROM 
5             (
6                 SELECT top 45030 ID, YEAR FROM ARTICLE ORDER BY YEAR DESC, ID DESC
7             ) w ORDER BY w.YEAR ASC, w.ID ASC
8         ) 
9     ORDER BY w1.YEAR DESC, w1.ID DESC;

平均查询100次所需时间:20S

第五种方案:

1 SELECT w2.n, w1.* FROM ARTICLE w1,(
2     SELECT TOP 50030 row_number() OVER (ORDER BY YEAR DESC, ID DESC) n, ID FROM ARTICLE) w2 
3 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:

1 SELECT TOP 30 * FROM ARTICLE WHERE ID NOT IN(
2     SELECT TOP 1000 ID FROM ARTICLE
3     ORDER BY YEAR DESC, ID DESC) 
4 ORDER BY YEAR DESC,ID DESC;

平均查询100次所需时间:80s

第二种方案:

1 SELECT * FROM(
2     SELECT TOP 30 * FROM (
3         SELECT TOP 1030 * FROM ARTICLE ORDER BY YEAR DESC, ID DESC) f 
4     ORDER BY f.YEAR ASC, f.ID DESC) s 
5 ORDER BY s.YEAR DESC,s.ID DESC;

平均查询100次所需时间:30S

第三种方案:

1 SELECT * FROM ARTICLE w1, 
2 (
3     SELECT TOP 30 ID FROM 
4     (
5         SELECT TOP 1030 ID, YEAR FROM ARTICLE ORDER BY YEAR DESC, ID DESC
6     ) w ORDER BY w.YEAR ASC, w.ID ASC
7 ) 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:

1 SELECT * FROM ARTICLE w1 
2     WHERE ID in 
3         (
4             SELECT top 30 ID FROM 
5             (
6                 SELECT top 1030 ID, YEAR FROM ARTICLE ORDER BY YEAR DESC, ID DESC
7             ) w ORDER BY w.YEAR ASC, w.ID ASC
8         ) 
9     ORDER BY w1.YEAR DESC, w1.ID DESC;

平均查询100次所需时间:13S

第五种方案:

1 SELECT w2.n, w1.* FROM ARTICLE w1,(
2     SELECT TOP 1030 row_number() OVER (ORDER BY YEAR DESC, ID DESC) n, ID FROM ARTICLE) w2 
3 WHERE w1.ID = w2.ID AND w2.n > 1000 
4 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:

 1 if exists (select * from dbo.sysobjects where id = object_id(N'[dbo].[sys_Page_v2]') and OBJECTPROPERTY(id, N'IsProcedure') = 1)
 2 drop procedure [dbo].[sys_Page_v2]
 3 GO
 4 CREATE PROCEDURE [dbo].[sys_Page_v2]
 5 @PCount int output,    --总页数输出
 6 @RCount int output,    --总记录数输出
 7 @sys_Table nvarchar(100),    --查询表名
 8 @sys_Key varchar(50),        --主键
 9 @sys_Fields nvarchar(500),    --查询字段
10 @sys_Where nvarchar(3000),    --查询条件
11 @sys_Order nvarchar(100),    --排序字段
12 @sys_Begin int,        --开始位置
13 @sys_PageIndex int,        --当前页数
14 @sys_PageSize int        --页大小
15 AS
16 SET NOCOUNT ON
17 SET ANSI_WARNINGS ON
18 IF @sys_PageSize < 0 OR @sys_PageIndex < 0
19 BEGIN        
20 RETURN
21 END
22 DECLARE @new_where1 NVARCHAR(3000)
23 DECLARE @new_order1 NVARCHAR(100)
24 DECLARE @new_order2 NVARCHAR(100)
25 DECLARE @Sql NVARCHAR(4000)
26 DECLARE @SqlCount NVARCHAR(4000)
27 DECLARE @Top int
28 if(@sys_Begin <=0)
29     set @sys_Begin=0
30 else
31     set @sys_Begin=@sys_Begin-1
32 IF ISNULL(@sys_Where,'') = ''
33     SET @new_where1 = ' '
34 ELSE
35     SET @new_where1 = ' WHERE ' + @sys_Where 
36 IF ISNULL(@sys_Order,'') <> '' 
37 BEGIN
38     SET @new_order1 = ' ORDER BY ' + Replace(@sys_Order,'desc','')
39     SET @new_order1 = Replace(@new_order1,'asc','desc')
40     SET @new_order2 = ' ORDER BY ' + @sys_Order
41 END
42 ELSE
43 BEGIN
44     SET @new_order1 = ' ORDER BY ID DESC'
45     SET @new_order2 = ' ORDER BY ID ASC'
46 END
47 SET @SqlCount = 'SELECT @RCount=COUNT(1),@PCount=CEILING((COUNT(1)+0.0)/'
48             + CAST(@sys_PageSize AS NVARCHAR)+') FROM ' + @sys_Table + @new_where1
49 EXEC SP_EXECUTESQL @SqlCount,N'@RCount INT OUTPUT,@PCount INT OUTPUT',
50                @RCount OUTPUT,@PCount OUTPUT
51 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
52 BEGIN
53     SET @sys_PageIndex =  CEILING((@RCount+0.0)/@sys_PageSize)
54 END
55 set @sql = 'select '+ @sys_fields +' from ' + @sys_Table + ' w1 '
56     + ' where '+ @sys_Key +' in ('
57         +'select top '+ ltrim(str(@sys_PageSize)) +' ' + @sys_Key + ' from '
58         +'('
59             +'select top ' + ltrim(STR(@sys_PageSize * @sys_PageIndex + @sys_Begin)) + ' ' + @sys_Key + ' FROM ' 
60         + @sys_Table + @new_where1 + @new_order2 
61         +') w ' + @new_order1
62     +') ' + @new_order2
63 print(@sql)
64 Exec(@sql)
65 GO

 

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