MySQL，将数据从长/高重塑到宽

交叉表或数据透视表就是答案。从那里可以选择SELECt FROM … INSERT INTO …或从单个SELECt创建一个VIEW。

就像是：

SELECT country,        MAX( IF( key='President', value, NULL ) ) AS President,       MAX( IF( key='Currency', value, NULL ) ) AS Currency,       ...FROM table GROUP BY country;

有关更多信息：http

//dev.mysql.com/tech-
resources/articles/wizard/index.html