Tsql通過買入/賣出查詢期間？

Question

代理商從工廠購買產品並將其銷售給正常人。

例如

他買蘋果（買入）（1/1/2010）

第二天，他又買蘋果（購買）（2/1/2010）

後來他買橙色（買入）（2/1/2010）

後來他賣蘋果（賣出）（3/1/2010）

後來他賣蘋果（賣出）（20/1/2010）

< = 這裏買/賣爲蘋果的週期結束。

銷售橙色（22/1/2010）

我需要查詢結果告訴我，每個週期 - 這一點：>

item | numberOfItems | timeFromBeginingToVanish 
------------------------------------------------------ 
apple    2     19 days     // (20/1 - 1/1) 
orange   1      20 days     //(22/1 - 2/1) 

通知：

他可以購買另一個蘋果，而不是賣給他 - 這個WONT在列表中。

僅當堆棧是先完成

Answer 1

編輯：我已經加入另一個濾波器（HAVING子句）只顯示那些completed週期。

此解決方案使用遞歸CTE：

1）來計算運行總數（RunningTotal）爲每個項目和

2）來產生用於每一個項目週期的組ID（PseudoDenseRank）。

CREATE TABLE [Transaction] 
(
    TransactionId INT IDENTITY(10,10) PRIMARY KEY 
    ,Item VARCHAR(100) NOT NULL 
    ,TransactionType CHAR(1) NOT NULL 
    ,Qty INT NOT NULL 
    ,TransactionDate DATE NOT NULL 
    ,CHECK(TransactionType IN ('B', 'S')) --Buy, Sell 
); 

INSERT [Transaction] 
SELECT 'apple', 'B', 1, '2010-01-01' 
UNION ALL 
SELECT 'apple', 'B', 1, '2010-01-02' 
UNION ALL 
SELECT 'orange','B', 1, '2010-01-03' 
UNION ALL 
SELECT 'apple', 'S', 1, '2010-01-03' 
UNION ALL 
SELECT 'apple', 'S', 1, '2010-01-20' 
UNION ALL 
SELECT 'orange','S', 1, '2010-01-22' 

UNION ALL 
SELECT 'apple', 'B', 2, '2010-02-01' 
UNION ALL 
SELECT 'orange','B', 3, '2010-02-02' 
UNION ALL 
SELECT 'apple', 'S', 1, '2010-02-03' 
UNION ALL 
SELECT 'apple', 'S', 1, '2010-02-10' 
UNION ALL 
SELECT 'orange','S', 1, '2010-02-10' 
UNION ALL 
SELECT 'orange','S', 1, '2010-02-11'; 

DECLARE @Results TABLE 
(
    TransactionId INT NOT NULL 
    ,Item VARCHAR(100) NOT NULL 
    ,TransactionType CHAR(1) NOT NULL 
    ,Qty INT NOT NULL 
    ,TransactionDate DATE NOT NULL 
    ,RowNum INT NOT NULL 
    ,PRIMARY KEY (Item, RowNum) 
); 

INSERT @Results 
SELECT * 
     ,ROW_NUMBER() OVER(PARTITION BY t.Item ORDER BY t.TransactionDate ASC, t.TransactionType ASC, t.TransactionId ASC) RowNum 
FROM [Transaction] t; 

WITH CteRecursive 
AS 
(
    SELECT q.Item 
      ,q.RowNum 
      ,CASE WHEN q.TransactionType = 'B' THEN q.Qty END QtyBuy 
      ,CASE WHEN q.TransactionType = 'S' THEN q.Qty END QtySell 
      ,q.TransactionDate 
      ,CASE WHEN q.TransactionType = 'B' THEN q.Qty WHEN q.TransactionType = 'S' THEN -q.Qty END AS RunningTotal 
      ,1 AS PseudoDenseRank 
    FROM @Results q 
    WHERE q.RowNum = 1 
    UNION ALL 
    SELECT prev.Item 
      ,crt.RowNum 
      ,CASE WHEN crt.TransactionType = 'B' THEN crt.Qty END QtyBuy 
      ,CASE WHEN crt.TransactionType = 'S' THEN crt.Qty END QtySell 
      ,crt.TransactionDate 
      ,prev.RunningTotal + CASE WHEN crt.TransactionType = 'B' THEN crt.Qty WHEN crt.TransactionType = 'S' THEN -crt.Qty END 
      ,CASE WHEN prev.RunningTotal = 0 THEN prev.PseudoDenseRank + 1 ELSE prev.PseudoDenseRank END 
    FROM CteRecursive prev 
    INNER JOIN @Results crt ON prev.Item = crt.Item 
    AND  prev.RowNum + 1 = crt.RowNum 
) 
SELECT q.Item 
     ,q.PseudoDenseRank  AS CycleNumber 
     ,SUM(q.QtyBuy)   AS QtyBuyTotal 
     ,SUM(q.QtySell)   AS QtySellTotal 
     ,CASE WHEN ISNULL(SUM(q.QtyBuy), 0) - ISNULL(SUM(q.QtySell),0) = 0 THEN 'Complete' ELSE 'Incomplete' END AS CycleStatus 
     ,MIN(q.TransactionDate) AS CycleStartDate 
     ,MAX(q.TransactionDate) AS CycleEndDate 
     ,CONVERT(VARCHAR(25), MIN(q.TransactionDate), 112) + ' - ' + CONVERT(VARCHAR(25), MAX(q.TransactionDate), 112) AS CycleInterval 
FROM CteRecursive q 
GROUP BY q.Item, q.PseudoDenseRank 
HAVING ISNULL(SUM(q.QtyBuy), 0) - ISNULL(SUM(q.QtySell),0) = 0 
ORDER BY q.Item, q.PseudoDenseRank; 

DROP TABLE [Transaction]; 

結果：

Item CycleNumber QtyBuyTotal QtySellTotal CycleStatus CycleStartDate CycleEndDate CycleInterval 
------ ----------- ----------- ------------ ----------- -------------- ------------ ----------------------- 
apple 1   2   2   Complete 2010-01-01  2010-01-20 2010-01-01 - 2010-01-20 
apple 2   2   2   Complete 2010-02-01  2010-02-10 2010-02-01 - 2010-02-10 
orange 1   1   1   Complete 2010-01-03  2010-01-22 2010-01-03 - 2010-01-22 
--The next row is eliminated by the filter from HAVING 
orange 2   3   2   Incomplete 2010-02-02  2010-02-11 2010-02-02 - 2010-02-11