在SQL中使用join進行多次和

Question

這是Rudresh BR，也嘗試通過求和將同一行的數據分成多列。 但是遇到了問題，請找到以下有關該問題的詳細信息，

預期數據：

但獲得的數據：

表中存在的數據

1. 項目清單

使用的查詢：

select 
    a.BM_BANK_NAME,
    SUM(PCBunit.BID_CURRENCY_VALUE) as PCBUnitSum,
     SUM(PTBunit.BID_CURRENCY_VALUE) as PTBUnitSum  
from 
     dbo.BG_Mtr_Bank_Master a 
     inner join dbo.BG_Tra_Issuance_Details PCBunit on a.BM_ID=PCBunit.BID_BANK_NAME and PCBunit.BID_UNIT_DIVISION='PCB' 
     inner join dbo.BG_Tra_Issuance_Details PTBunit on a.BM_ID=PTBunit.BID_BANK_NAME and PTBunit.BID_UNIT_DIVISION='PTB' 
group by 
     a.BM_BANK_NAME,
     PCBunit.BID_UNIT_DIVISION,
     PTBunit.BID_UNIT_DIVISION

PCBUnitSum和PTBUnitSum分別是PCB和PTB的BID_Currency_Value行的總和。

我觀察到的是，總和完成后即3000（我期望作為輸出），它根據PCB和PTB的行數分別重做總和，因此有3行PCB，即3000 + 3000 + 3000 O / P = 9000。

我要求所有人，請幫助我找出問題所在？

Answer 1

不要自加入表，用例

select a.BM_BANK_NAME
     , SUM(case when t.BID_UNIT_DIVISION ='PCB' then t.BID_CURRENCY_VALUE end) as PCBUnitSum
     , SUM(case when t.BID_UNIT_DIVISION ='PTB' then t.BID_CURRENCY_VALUE end) as PTBUnitSum  
  from dbo.BG_Mtr_Bank_Master a 
 inner 
  join dbo.BG_Tra_Issuance_Details t 
    on a.BM_ID = t.BID_BANK_NAME 
   and t.BID_UNIT_DIVISION in ('PCB', 'PTB')
 group  
    by a.BM_BANK_NAME

Answer 2

嘗試這個：

DECLARE @list_item TABLE ( unit NVARCHAR(5),bank NVARCHAR(5),curr INT)
INSERT INTO @list_item VALUES ('PCB','SBI',1000),('PCB','SBI',1000),
('PCB','SBI',1000),('PTB','SBI',1000),('PTB','SBI',1000),
('PTB','SBI',1000)

SELECT bank,
SUM(CASE WHEN unit='PCB' THEN curr END) PCBUnitSum,
SUM(CASE WHEN unit='PTB' THEN curr END) PTBUnitSum
FROM ( SELECT unit,bank,SUM(curr)curr FROM @list_item 
group by unit,bank ) A GROUP BY bank

這可能會有所幫助。 :)