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
