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HomeDatabaseMysql Tutorial让SELECT 查询结果额外增加自动递增序号

让SELECT 查询结果额外增加自动递增序号

Jun 07, 2016 pm 02:54 PM
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如果数据表本身并不内含自动地增编号的字段时,要怎么做才能够让SELECT查询结果,额外增加自动递增序号呢?我们提供下列五种方法供您参考: 自增长 USE 2 GO 3 4 /* 方法一*/ 5 6 SELECT序号= (SELECT COUNT(客户编号) FROM 客户 AS LiMing 7 WHERE LiMing.

如果数据表本身并不内含自动地增编号的字段时,要怎么做才能够让SELECT查询结果,额外增加自动递增序号呢?我们提供下列五种方法供您参考: 自增长
USE
 2 GO
 3 
 4 /* 方法一*/
 5 
 6 SELECT序号= (SELECT COUNT(客户编号) FROM 客户 AS LiMing
 7                      WHERE LiMing.客户编号<= Chang.客户编号),
 8         客户编号,公司名称
 9 FROM客户 AS Chang ORDER BY 1;
10 GO
11 
12 /* 方法二: 使用SQL Server 2005 独有的RANK() OVER () 语法*/
13 SELECT RANK() OVER (ORDER BY 客户编号 DESC) AS 序号,
14           客户编号,公司名称
15 FROM客户;
16 GO
17 
18 /* 方法三*/
19 SELECT序号= COUNT(*), LiMing.客户编号, LiMing.公司名称
20     FROM 客户 AS LiMing, 客户AS Chang
21     WHERE LiMing.客户编号>= Chang.客户编号
22     GROUP BY LiMing.客户编号, LiMing.公司名称
23     ORDER BY 序号;
24 GO
25 
26 /* 方法四
27 建立一个「自动编号」的字段,然后将数据新增至一个区域性暂存数据表,
28 然后由该区域性暂存数据表中,将数据选取出来,最后删除该区域性暂存数据表
29 */
30 SELECT序号= IDENTITY(INT,1,1),管道,程序语言,讲师,资历
31 INTO #LiMing
32 FROM问券调查一;
33 GO
34 SELECT * FROM #LiMing;
35 GO
36 DROP TABLE #LiMing;
37 GO
38 
39 /*
40 方法五
41 使用 SQL Server 2005 独有的ROW_NUMBER() OVER () 语法
42 搭配 CTE (一般数据表表达式,就是 WITH 那段语法)选取序号2 ~ 4 的数据
43 */
44 WITH排序后的图书 AS
45 (SELECT ROW_NUMBER() OVER (ORDER BY 客户编号 DESC) AS 序号,
46    客户编号,公司名称
47     FROM 客户)
48 SELECT * FROM 排序后的图书
49 WHERE序号 BETWEEN 2 AND 4;
50 GO
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