用不同的條件子查詢同一列

Question

我正在嘗試編寫一個子查詢來從我已經使用主查詢選擇的列之一中檢索值，但條件不同。

在此處輸入圖像描述

Answer 1

你能試試這個嗎，我想你可以使用收費和信用的子查詢：

SELECT DISTINCT
       [date],[customer],
       Charge = (SELECT Revenue FROM TABLE t2 WHERE t2.customer = t1.customer AND t2.[type] = 'Charge'), 
       Credit = (SELECT Revenue FROM TABLE t2 WHERE t2.customer = t1.customer AND t2.[type] = 'Credit')
FROM TABLE t1

使用示例數據：

CREATE TABLE #temp (thedate date, customer VARCHAR(100), revenue INT, [type] VARCHAR(100))
INSERT INTO #temp values ('2019-01-01','a',10,'charge'),('2019-01-01','a',20,'Credit'),('2019-01-01','b',30,'charge')

SELECT DISTINCT
       [thedate], [customer],
       Charge = (SELECT Revenue FROM #temp t2 WHERE t2.customer = t1.customer AND t2.[type] = 'Charge'), 
       Credit = (SELECT Revenue FROM #temp t2 WHERE t2.customer = t1.customer AND t2.[type] = 'Credit')
FROM #temp t1

Answer 2

我相信這就是您正在尋找的：

CREATE TABLE #temp (thedate date, customer VARCHAR(100), revenue INT, [type] VARCHAR(100))

INSERT INTO #temp values ('2019-01-01','Acme, Inc.',1000,'Charge')
                        ,('2019-01-01','Amazon',500,'Charge')
                        ,('2019-01-01','Acme, Inc.',100,'Credit')

SELECT [Date]
    , [Customer]
    , [Revenue] as [Charge]
    , [Credit]
FROM #temp t1
OUTER APPLY (
    SELECT sum(revenue) credit
    FROM #temp t2
    WHERE t1.customer = t2.customer
        AND t2.[type] = 'credit'
    ) x
WHERE t1.[type] = 'charge'

僅根據您的輸入數據和預期結果判斷，上述查詢就足夠了。 但是，您在問題上發布的評論與預期結果的圖像顯示的內容略有矛盾。

這是我查詢的 output，根據您的輸入數據：

Answer 3

CREATE TABLE #temp (thedate date, customer VARCHAR(100), revenue INT, [type] VARCHAR(100))

INSERT INTO #temp values ('2019-01-01','Acme, Inc.',1000,'Charge')
                        ,('2019-01-01','Amazon',500,     'CREDIT')
                        ,('2019-01-01','Acme, Inc.',100, 'Credit')


SELECT  THEDATE,
        CUSTOMER,
        MAX(CASE
            WHEN TYPE = 'CREDIT' THEN revenue
        END) AS CREDIT,
        MAX(CASE
            WHEN TYPE = 'CHARGE' THEN REVENUE
        END) AS CHARGE
FROM #TEMP
GROUP BY CUSTOMER, THEDATE

或者你可以試試 PIVOT Function

SELECT  *
FROM #TEMP
PIVOT (MAX(REVENUE)
        FOR 
        [TYPE] IN ([CHARGE],[CREDIT])
        ) AS PIV