SQL查询来转换表

我遇到了一个问题，看起来像这样

city | distributor | phno --------------------------------- new york xxx 12345 new york yyy 12312 new york zzz 12313 london aaa 12315 london bbb 11111 hong konk ccc 12311 

成

 city | distributor1 | phno1 | distributor2 | phno2 | distributor3 | phno3 ----------------------------------------------------------------------------- new york xxx 12345 yyy 12312 zzz 12313 london aaa 12315 bbb 11111 0 0 hong konk ccc 12311 0 0 0 0 

• 因为任何一个城市都不多，三个分销商

我已经尝试了自我join，但我得到重复的logging，请指教。

让我知道如果这是在Excel中完成？ 因为这仅用于报告目的

Answer 1

您也可以在SQL中使用PIVOT表。

http://msdn.microsoft.com/en-us/library/ms177410.aspx

Answer 2

我认为这种转变最好在报告作者中完成，而不是在数据库中完成。

Answer 3

我不确定它在Sybase SQL中是否有效，但是我仍然会在其他SQL服务器中以类似的方式开始：

 SELECT * FROM (SELECT city FROM table GROUP BY city) AS c LEFT JOIN (SELECT TOP 1 distributor AS distributor1, phno AS phno1 FROM table c1 WHERE c1.city = c.city ORDER BY distributor ASC) AS c1 ON true LEFT JOIN (SELECT TOP 2 distributor AS distributor2, phno AS phno2 FROM table c2 WHERE c2.city = c.city ORDER BY distributor ASC) AS c2 ON distributor1 != distributor2 LEFT JOIN (SELECT TOP 3 distributor AS distributor3, phno AS phno3 FROM table c3 WHERE c3.city = c.city ORDER BY distributor ASC) AS c3 ON distributor1 != distributor3 AND distributor2 != distributor3