Oracle: Курсор Процедура: сумма 2 таблицы с соединением

Question

У меня есть 3 таблицы.

Table1

|Obj_id|Obj_Name| 
---------------- 
|A  |  AAA| 
|B  |  BBB| 
|C  |  CCC| 

Table2

|Obj_id|Amount1| 
---------------- 
|A  | 1000| 
|C  |  20| 
|A  | 100| 
|B  |  50| 
|C  |  10| 

Таблица3

|Obj_id|Amount2| 
---------------- 
|B  | 500| 
|C  |  10| 
|C  |  40| 

Теперь мне нужно создать процедуру "отчет", который возвращает курсор, как показано ниже

Report

|Obj_Name|Amount1|Amount2|Obj_id| 
--------------------------------- 
|AAA  | 1100|  0|A  | 
|BBB  |  50| 500|B  | 
|CCC  |  30|  50|C  | 

Я googled везде, но нет соответствующего ответа.

Answer 1

Попробуйте

SELECT 
    T1.Obj_Name 
    ,NVL(T2.Amount1,0) AS Amount1 
    ,NVL(T3.Amount2,0) AS Amount2 
    ,NVL(T1.Obj_id ,0) AS Obj_id 
FROM Table1 T1 
LEFT JOIN Table2 T2 ON T1.Obj_id = T2.Obj_id 
LEFT JOIN Table3 T3 ON T1.Obj_id = T3.Obj_id 
ORDER BY T1.Obj_Name 

SQL FIDDLE DEMO

ВЫВОД

Obj_Name Amount1 Amount2 Obj_id 
AAA  1000  0  A 
BBB  0  500  B 
CCC  20  10  C 

EDIT

SELECT 
    T1.Obj_Name AS Obj_Name 
    ,NVL(T2.Amount1,0) AS Amount1 
    ,NVL(T3.Amount2,0) AS Amount2 
    ,T1.Obj_id AS Obj_id 
FROM Table1 T1 
LEFT JOIN (SELECT Obj_id,SUM(Amount1) AS Amount1 FROM Table2 GROUP BY Obj_id) T2 ON T1.Obj_id = T2.Obj_id 
LEFT JOIN (SELECT Obj_id,SUM(Amount2) AS Amount2 FROM Table3 GROUP BY Obj_id) T3 ON T1.Obj_id = T3.Obj_id 
ORDER BY T1.Obj_Name; 

SQL FIDDLE DEMO UPDATED

ВЫВОД

OBJ_NAME AMOUNT1 AMOUNT2 OBJ_ID 
AAA  1100  0  A 
BBB  50   500 B 
CCC  30   50  C