让SELECT 查询结果额外增加自动递增序号
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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