移調一個表甲骨文10

Question

我讀過一些問題，但目前尚不清楚對我來說，我不能用樞軸

我有下表：

ID AREA CAR 
1 A1 A 
1 A2 B 
1 A3 C 
2 A1 D 
2 A2 E 
3 A2 F 
3 A3 G 

而且我想一些像

ID AREA1 CAR1 AREA2 CAR2 AREA3 CAR3 
1  A1  A A2  B  A3 C   
2  A1  D A2  D  null null     
3 null null A2  F  A3 G      

區域的數量是固定的，只是A1，A2，A3。

我試着

SELECT  id, area1,car1,area2,car2 
FROM  ( SELECT  id, 
         case when AREA='A1' then AREA else NULL end area1, 
         case when AREA='A1' then CAR else NULL end car1, 
         case when AREA='A2' then AREA else NULL end area2, 
         case when AREA='A2' then CAR else NULL end car2, 
         case when AREA='A3' then AREA else NULL end area3, 
         case when AREA='A3' then CAR else NULL end car3 
      FROM  TABLA 
      GROUP BY id); 

，但我得到：

"not a GROUP BY expression" 

我能做些什麼有一個正確的GROUP BY表達和正常轉我的表？ 有沒有更好的解決方案呢？

在此先感謝

Answer 1

遺憾的是，在Oracle 10沒有旋轉功能您所查詢的是接近，但有不需要包裝其他查詢裏面：

select id, 
    min(case when area = 'A1' then area end) area1, 
    min(case when area = 'A1' then car end) car1, 
    min(case when area = 'A2' then area end) area2, 
    min(case when area = 'A2' then car end) car2, 
    min(case when area = 'A3' then area end) area3, 
    min(case when area = 'A3' then car end) car3 
from yourTable 
group by id 

Answer 2

當你做一個GROUP BY，你需要聚合，你是不是分組任何列。你可能想是這樣

SELECT  id, area1,car1,area2,car2 
FROM  ( SELECT  id, 
         max(case when AREA='A1' then AREA else NULL end) area1, 
         max(case when AREA='A1' then CAR else NULL end) car1, 
         max(case when AREA='A2' then AREA else NULL end) area2, 
         max(case when AREA='A2' then CAR else NULL end) car2, 
         max(case when AREA='A3' then AREA else NULL end) area3, 
         max(case when AREA='A3' then CAR else NULL end) car3 
      FROM  TABLA 
      GROUP BY id); 

你也可以移動的聚集和GROUP BY到外部查詢

SELECT  id, max(area1),max(car1),max(area2),max(car2) 
FROM  ( SELECT  id, 
         case when AREA='A1' then AREA else NULL end area1, 
         case when AREA='A1' then CAR else NULL end car1, 
         case when AREA='A2' then AREA else NULL end area2, 
         case when AREA='A2' then CAR else NULL end car2, 
         case when AREA='A3' then AREA else NULL end area3, 
         case when AREA='A3' then CAR else NULL end car3 
      FROM  TABLA) 
GROUP BY id;