SQL - 將多行合併爲一個空行值，包括空值

Question

我一直在尋找答案但沒有找到。我認爲這可能是由於我不知道要搜索什麼條款。另外，這是我的第一篇文章，所以我想道歉，如果我使用不正確的格式。

我需要以下輸出：

Invoice | Inv Date | Created by | Destination | Goods $ | Freight | Insurance $ | 
33813..| 12 Dec ..| Jack ........| Cape Town | 250.00 ..| 50.00 ..| 10.00 ...| 
33814..| 12 Dec ..| Jenny .........| Durban ......| 5,000.00| 20.00 ..| ....| 

前5列是從使用發票列作爲指標各列建立。

然後我想添加運費和保險。這是在不同的表託管與以下佈局：

InvCostID | Invoice | Cost Code | Cost Description | Value |<br/> 
556 ..........| 33813 .| 1 ...............| Freight ...............| 50.00 | 
559 ..........| 33813 .| 2 ...............| Insurance ...........| 10.00 | 
570 ..........| 33814 .| 1 ...............| Freight ...............| 20.00 | 

的問題是，我不能只選擇列，包括了在運費和保險費是在不同的行。爲了解決這個問題，我創建了兩個「子表」。一個是成本代碼是1（因此是貨運表），另一個是成本代碼2（保險表）。

然後我只是從正確的表中選擇值。

問題：如果其中一個成本要素不存在（例如發票33814的保險），我當前的查詢將完全從結果中排除該發票。 （與上面的表，我下面的代碼只會顯示發票33813.

select 
IT.Invoice as 'Invoice', 
IT.InvDate as 'Inv Date', 
UT.UserFullName as 'Created by', 
IT.DestinationDescription as 'Destination', 
IT.USDVal as 'Goods $', 
FREIGHTLIST.Value as 'FREIGHT $', 
INSURANCELIST.Value as 'INSURANCE $' 

from InvoiceTable IT, 
UserTable UT, 
(select * from SundryCostTable where CostCode = 1) as FREIGHTLIST, 
(select * from SundryCostTable where CostCode = 2) as INSURANCELIST 

where IT.InvDate > '2014-12-01' 
and IT.UserId = UT.UserId 
and IT.Invoice = FREIGHTLIST.Invoice 
and IT.Invoice = INSURANCELIST.Invoice 

請幫助。

謝謝 尼科

（我使用SQL Server Management Studio中運行該查詢）

Answer 1

select 
IT.Invoice as 'Invoice', 
IT.InvDate as 'Inv Date', 
UT.UserFullName as 'Created by', 
IT.DestinationDescription as 'Destination', 
IT.USDVal as 'Goods $', 
FREIGHTLIST.Value as 'FREIGHT $', 
INSURANCELIST.Value as 'INSURANCE $' 

from InvoiceTable IT 
join UserTable UT on IT.UserId = UT.UserId 
left join SundryCostTable as FREIGHTLIST on CostCode = 1 and IT.Invoice = FREIGHTLIST.Invoice 
left join SundryCostTable as INSURANCELIST on CostCode = 2 and IT.Invoice = INSURANCELIST.Invoice 

where IT.InvDate > '2014-12-01' 

注意的情況下，才能使用LEFT JOIN不排除IT和UT行沒有匹配FREIGHTLIST或INS URANCELIST。

看看this的帖子瞭解更多關於JOIN（s）的使用。

Answer 2

您可以使用子查詢來代替Aquillo所描述的LEFT JOIN。以下查詢將處理FREIGHT和INSURANCE的NULL值。

SELECT 
IT.Invoice as 'Invoice', 
IT.InvDate as 'Inv Date', 
UT.UserFullName as 'Created by', 
IT.DestinationDescription as 'Destination', 
IT.USDVal as 'Goods $', 
ISNULL((select Top 1 Value from SundryCostTable where CostCode = 1 And SundryCostTable.Invoice=IT.Invoice),0) as 'FREIGHT $', 
ISNULL((select Top 1 Value from SundryCostTable where CostCode = 2 And SundryCostTable.Invoice=IT.Invoice),0) as 'INSURANCE $' 

from InvoiceTable IT, 
UserTable UT 

where IT.InvDate > '2014-12-01' 
and IT.UserId = UT.UserId