排除除一個不同字段以外的重複記錄

Question

我有包含客戶編號，日期，金額和交易類型（買入或賣出）的交易列表。我只想返回未被相同客戶，日期和金額取消但具有相反交易類型的交易（每位客戶，每天，每筆金額）。

例如，我的示例表（交易）低於：

 
+----------+------------+--------+--------+ 
| Customer | Date | Amount | Action | 
+----------+------------+--------+--------+ 
|  1111 | 15/09/2016 |  5 | Buy | 
|  2222 | 15/09/2016 |  5 | Sell | 
|  3333 | 15/09/2016 |  6 | Buy | 
|  3333 | 15/09/2016 |  6 | Sell | 
|  4444 | 15/09/2016 |  7 | Sell | 
|  2222 | 15/09/2016 |  6 | Buy | 
+----------+------------+--------+--------+ 

我只想以下項目返回：

 
+----------+------------+--------+--------+ 
| Customer | Date | Amount | Action | 
+----------+------------+--------+--------+ 
|  1111 | 15/09/2016 |  5 | Buy | 
|  2222 | 15/09/2016 |  5 | Sell | 
|  4444 | 15/09/2016 |  7 | Sell | 
|  2222 | 15/09/2016 |  6 | Buy | 
+----------+------------+--------+--------+ 

客戶3333已經被排除在外，因爲他們有一個買入和在同一天出售相同價值的金額。客戶2222已被留下，儘管他們在同一天進行了買賣，這是針對不同的金額，所以我需要爲他們返回兩個記錄。

Answer 1

這將是不夠的：

SELECT Customer, Date, Amount, MAX(Action) Action 
FROM Src 
GROUP BY Customer, Date, Amount 
HAVING COUNT(*)=1 

測試用例

WITH Src AS 
(
    SELECT * FROM (VALUES 
    (1111, '15/09/2016', 5, 'Buy'), 
    (2222, '15/09/2016', 5, 'Sell'), 
    (3333, '15/09/2016', 6, 'Buy'), 
    (3333, '15/09/2016', 6, 'Sell'), 
    (4444, '15/09/2016', 7, 'Sell'), 
    (2222, '15/09/2016', 6, 'Buy') 
    ) T(Customer, Date, Amount, Action) 
) 
SELECT Customer, Date, Amount, MAX(Action) Action 
FROM Src 
GROUP BY Customer, Date, Amount 
HAVING COUNT(*)=1 

結果

Customer Date  Amount  Action 
----------- ---------- ----------- ---- 
1111  15/09/2016 5   Buy 
2222  15/09/2016 5   Sell 
2222  15/09/2016 6   Buy 
4444  15/09/2016 7   Sell