怎么样将SQL Server纵表与横表相互转换?
怎么样将SQL Server纵表与横表相互转换?
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路饭网站的支持!