Question

我需要将 Header 和 Detail 行加入到一个结果集中：

（样本DDL和inserts要遵循）：

订单：

OrderID  OrderDate                CurrencyID  BuyAmount  BuyRate 
=======  =======================  ==========  =========  ========
1        2011-09-01 15:57:00.000  7           12173.60   1.243893
1        2011-09-01 15:57:00.000  9           69.48      1

订单明细：

OrderID  CurrencyID  SellAmount  SellRate
=======  ==========  ==========  ========
1        7           10000       1
1        8           12384       0.9638

我希望他们加入OrderID和CurrencyID：

OrderID  CurrencyID  BuyAmount  BuyRate   SellAmount  SellRate
=======  ==========  =========  ========  ==========  ========
1        7           12173.60   1.243893  10000       1
1        8           NULL       NULL      12384       0.9638
1        9           69.48      1         NULL        NULL

示例脚本

--USE Scratch

--Create a temporary `Orders` and, `OrderDetails` tables:
IF OBJECT_ID('tempdb..#Orders') > 0 DROP TABLE #Orders
CREATE TABLE #Orders
(
    OrderID int NOT NULL,
    OrderDate datetime NOT NULL,
    CurrencyID int NOT NULL,
    BuyAmount money NOT NULL,
    BuyRate real NOT NULL
)

IF OBJECT_ID('tempdb..#OrderDetails') > 0 DROP TABLE #OrderDetails
CREATE TABLE #OrderDetails
(
    OrderID int NOT NULL,
    CurrencyID int NOT NULL,
    SellAmount money NOT NULL,
    SellRate real NOT NULL
)

-- **Insert sample data:**

INSERT INTO #Orders (OrderID, OrderDate, CurrencyID, BuyAmount, BuyRate) 
VALUES (1, '20110901 15:57:00', 7, 12173.60, 1.2438933)
INSERT INTO #Orders (OrderID, OrderDate, CurrencyID, BuyAmount, BuyRate) 
VALUES (1, '20110901 15:57:00', 9, 69.48, 1)


INSERT INTO #OrderDetails (OrderID, CurrencyID, SellAmount, SellRate)
VALUES (1, 7, 10000, 1)
INSERT INTO #OrderDetails (OrderID, CurrencyID, SellAmount, SellRate)
VALUES (1, 8, 12384, 0.9638)


/*Desired Output:
OrderID  CurrencyID  BuyAmount  BuyRate   SellAmount  SellRate
=======  ==========  =========  ========  ==========  ========
1        7           12173.60   1.243893  10000       1
1        8           NULL       NULL      12384       0.9638
1        9           69.48      1         NULL        NULL

*/

我找不到可以产生所需输出的RIGHT OUTER JOIN，FULL OUTER JOIN，COALESCE的组合。

更新

OrderDetails表中的CurrencyID也可能不包含匹配的Orders：

订单：

OrderID  CurrencyID  BuyAmount  BuyRate 
=======  ==========  =========  ========
1        7           12173.60   1.243893
1        9           69.48      1

订单明细：

OrderID  CurrencyID  SellAmount  SellRate
=======  ==========  ==========  ========
1        8           12384       0.9638

Answer 1

那么，你试过这个吗？

SELECT
  COALESCE(o.OrderID, od.OrderID) AS OrderID,
  COALESCE(o.CurrencyID, od.CurrencyID) AS CurrencyID,
  o.BuyAmount,
  o.BuyRate,
  od.SellAmount,
  od.SellRate
FROM
  #Orders AS o
  FULL OUTER JOIN #OrderDetails AS od ON o.OrderID = od.OrderID AND o.CurrencyID = od.CurrencyID

Answer 2

SELECT od.OrderID, od.CurrencyID, o.BuyAmount, o.BuyRate, od.SellAmount, od.SellRate
    FROM #OrderDetails od
        LEFT JOIN #Orders o
            ON od.OrderID = o.OrderID
                AND od.CurrencyID = o.CurrencyID

完全外连接在一个标准上，内连接在另一个标准上

示例脚本

2 个答案: