如果将行选择为多列

Question

您好，我正在寻求帮助，我的查询当前运行没有错误，但不显示数据，因为我也需要它。我的表存储电话号码，相关字段是id，phonetype和phonenumber。

运行时，虽然它只显示最后一个数字，但它会按预期方式返回列id,HOME PHONE,WORK PHONE,CELL PHONE。假设在给定行中有家庭电话和工作电话号码...我只在该工作电话的WORK PHONE列中获取数据。如果连续存在家庭电话，工作电话和手机...我只能在CELL PHONE列中获取数据。

我需要在phonetype类型的唯一列中给定id的所有电子形式的一行。我希望是有道理的，如果没有查询应该给你一个想法是什么即时寻找...感谢

SELECT id, 
(IF(phonetype = 'HOME PHONE', phonenumbers.phonenumber, '')) AS 'HOME PHONE', 
(IF(phonetype = 'WORK PHONE', phonenumbers.phonenumber, '')) AS 'WORK PHONE', 
(IF(phonetype = 'CELL PHONE', phonenumbers.phonenumber, '')) AS 'CELL PHONE' 
FROM phonenumbers 
GROUP BY id; 

表我查询看起来像这样

id | name | phonetype | phonenumber 

1 | Jim | HOME PHONE | 0000000001   
1 | Jim | WORK PHONE | 0000000002 
2 | Kim | HOME PHONE | 0000000003 
2 | Kim | WORK PHONE | 0000000004 
2 | Kim | CELL PHONE | 0000000005 

结果我我想找应该是这样的......

id | name | home phone | work phone | cell phone 

1 | Jim | 0000000001 | 0000000002 | 
2 | Kim | 0000000003 | 0000000004 | 0000000005 

Answer 1

假定每个ID都有反对每种类型的只有一个电话号码：

SELECT a.id, 
(SELECT phonenumbers.phonenumber FROM phonenumbers WHERE phonetype = 'HOME PHONE' AND id = a.id) AS 'HOME PHONE', 
(SELECT phonenumbers.phonenumber FROM phonenumbers WHERE phonetype = 'WORK PHONE' AND id = a.id) AS 'WORK PHONE', 
(SELECT phonenumbers.phonenumber FROM phonenumbers WHERE phonetype = 'CELL PHONE' AND id = a.id) AS 'CELL PHONE' 
FROM phonenumbers a 
GROUP BY a.id; 

可能会有所帮助。 干杯。