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SQL Server纵表与横表相互转换的方法

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1,纵表转横表 纵表结构 Table_A: 转换后的结构: 纵表转横表的SQL示例: SELECT Name ,SUM(CASE WHEN Course = N'语文' THEN GradeELSE 0END) AS Chinese ,SUM(CASE WHEN Course = N'数学' THEN GradeELSE 0END) AS Mathema

1,纵表转横表

纵表结构 Table_A:

转换后的结构:

纵表转横表的SQL示例:

SELECT Name ,
SUM(CASE WHEN Course = N'语文' THEN Grade
ELSE 0
END) AS Chinese ,
SUM(CASE WHEN Course = N'数学' THEN Grade
ELSE 0
END) AS Mathematics ,
SUM(CASE WHEN Course = N'英语' THEN Grade
ELSE 0
END) AS English
FROM dbo.Table_A
GROUP BY Name

2,横表转纵表

横表结构Table_B:

转换后的表结构:

横表转纵表的SQL示例:

SELECT Name ,
'Chinese' AS Course ,
Chinese AS Score
FROM dbo.Table_B
UNION ALL
SELECT Name ,
'Mathematics' AS Course ,
Mathematics AS Score
FROM dbo.Table_B
UNION ALL
SELECT Name ,
'English' AS Course ,
English AS Score
FROM dbo.Table_B
ORDER BY Name ,
Course DESC 

 以上所述是小编给大家介绍的SQL Server纵表与横表相互转换的实现方法,希望对大家有所帮助,如果大家有任何疑问请给我留言,小编会及时回复大家的。在此也非常感谢大家对易盾网络网站的支持!

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