查詢的正確性

Question

我很想知道我的查詢的正確性如何發佈問題here。，我懷疑如果我寫了一個完美的問題，並且我想問問大家哪裏可以改進我的代碼。

注：我不想用很多代碼填充這個地方，很簡短。謝謝。

SELECT a.BookingId       AS BookingId, 
     CAST(b.TransactionDateTime AS DATE) AS TransactionDate 
FROM TC33_AuditTrial A 
     JOIN TC33_AuditTrial b 
     ON  a.AuditId     = b.AuditId 
WHERE a.TransactionType     = 'S' 
AND CAST(a.TransactionDateTime AS DATE) = 
     (SELECT CAST(b.TransactionDateTime AS DATE) 
     FROM TC33_AuditTrial b 
     WHERE b.BookingId = a.BookingId 
     AND  b.AuditId = 
       (SELECT MAX(b.AuditId) 
       FROM TC33_AuditTrial b 
       WHERE a.BookingId  = b.BookingId 
       AND  b.TransactionType = 'R' 
       ) 
     ) 
AND a.TransactionValue = 
     (SELECT SUM(b.TransactionValue) 
     FROM TC33_AuditTrial b 
     WHERE a.BookingId  = b.BookingId 
     AND  b.TransactionType = 'R' 
     ) 

Answer 1

未刪除

我原來的答覆是

SELECT BookingId, CONVERT(VARCHAR(8), TransactionDateTime, 112) AS TransactionDate 
FROM TC33_AuditTrial 
GROUP BY BookingId, CONVERT(VARCHAR(8), TransactionDateTime, 112) 
HAVING 
SUM(CASE TransactionType WHEN 'S' THEN TransactionValue END) <= 
SUM(CASE TransactionType WHEN 'R' THEN TransactionValue END) 
ORDER BY BookingID 

這讓我很高興，因爲它只是把一次通過數據。

然後我注意到規範的更新位，它必須限制在包含該預訂條目的第一個日期。我能想到做到這一點的唯一方法是添加一個子查詢，從而顯着增加了查詢的成本。

令人沮喪的方面是，雖然我想結果限制爲每個BookingId的第一天，我已經通過BookingId，日編組

感覺就像有可能會得到這個限制沒有一些聰明的辦法子查詢，但如果是的話，迄今爲止它已經躲過了我！

我剛剛設法讓'OVER'工作。我不會公佈這個答案，直到比賽被關閉後，除了它具有完全相同的查詢計劃的發表8KB

WITH X AS 
(
SELECT BookingId, 
     RANK() OVER(PARTITION BY BookingId ORDER BY CONVERT(VARCHAR(8), TransactionDateTime, 112)) AS Rnk, 
     CONVERT(VARCHAR(8), TransactionDateTime, 112) AS TransactionDate, 
     SUM(CASE TransactionType WHEN 'S' THEN TransactionValue END) AS S, 
     SUM(CASE TransactionType WHEN 'R' THEN TransactionValue END) AS R 
FROM  TC33_AuditTrial t1 
GROUP BY BookingId, 
     CONVERT(VARCHAR(8), TransactionDateTime, 112) 
) 

SELECT BookingId, TransactionDate 
FROM X 
WHERE Rnk = 1 AND S<=R 
ORDER BY BookingID 

Answer 2

了一個曾在太跳...

SELECT 
    BookingID, 
    CONVERT(VARCHAR(8), TransactionDateTime, 112) AS TransactionDate 
FROM (
SELECT 
    BookingID, 
    TransactionDateTime, 
    COALESCE(pvt.S,0) AS Sale, 
    COALESCE(pvt.R,0) AS Receipt, 
    ROW_NUMBER() OVER (
    PARTITION BY BookingID ORDER BY (TransactionDateTime)) AS Rn 
FROM (
    SELECT 
    BookingID, 
    DATEADD(DD, DATEDIFF(DD,0,TransactionDateTime), 0) AS TransactionDateTime, 
    TransactionType, 
    TransactionValue 
    FROM TC33_AuditTrial 
) t 
PIVOT (
    SUM(TransactionValue) 
    FOR TransactionType IN (S,R) 
) AS pvt 
) t2 
WHERE Receipt >= Sale 
AND Rn = 1