在子查詢中帶有多部分標識符問題的SQL查詢

Question

我有一個查詢應該返回「status」--duration條目的總和。持續時間通過使用datediff計算（n，datestamp，（返回結束當前狀態的日期戳記的子查詢，即發現下一個配件「狀態更改」 - 在鎖定的那個之後進入）

我的問題是以下查詢返回的多部分的標識符錯誤

• 的INC表給我 「INCIDENT_NUMBER」我正在尋找至極的其他表中相關 「NUMBER」
• ACTM1保存所有DATESTAMP-條目
• ACTA1與ACTM1通過「THENU」 MBER」，並保存有關條目是否是一個裝配狀態更改或不是所有的信息

代碼：

SELECT SUM(DATEDIFF(n, ACTM1.DATESTAMP, END_DATESTAMP_TABLE.END_DATESTAMP)) 
FROM INC    LEFT OUTER JOIN 
    ACTM1 ON INC.INCIDENT_NUMBER = ACTM1.NUMBER LEFT OUTER JOIN 
    ACTA1 ON ACTM1.THENUMBER = ACTA1.THENUMBER LEFT OUTER JOIN 
/**/ 
    (SELECT ACTM1_1.NUMBER, ACTM1_1.DATESTAMP AS END_DATESTAMP 
    FROM ACTM1 AS ACTM1_1    LEFT OUTER JOIN 
/**/ 
     (SELECT ACTM1_1_1.NUMBER, MIN(ACTM1_1_1.THENUMBER) AS FOLLOWUP_THENUMBER 
    FROM ACTM1 AS ACTM1_1_1 
    WHERE (ACTM1_1_1.THENUMBER > /**/ ACTM1_1.THENUMBER)/*I think here lies the problem*/ 
     AND (ACTM1_1_1.[TYPE] IN ('Open', 'Status Change', 'Resolved', 'Closed'))) 
    AS FOLLOWUP_THENUMBER_TABLE 
/**/ 
      ON ACTM1_1.NUMBER = FOLLOWUP_THENUMBER_TABLE.NUMBER) 
    AS END_DATESTAMP_TABLE 
/**/ 
      ON ACTM1.NUMBER = END_DATESTAMP_TABLE.NUMBER 
WHERE ... 

我將是任何有幫助的評論感謝或暗示你能給我這個，

PS

Answer 1

左側加盟關係不能引用右側，因此這是非法的：

SELECT ... 
FROM A 
JOIN (SELECT ...FROM ... WHERE ... = A.Field) AS B ON A.ID = B.ID; 

使用應用操盤手：

SELECT ... 
FROM A 
APPLY (SELECT ...FROM ... WHERE ... = A.Field AND ID = A.ID) AS B; 

在你的情況很可能會像下面：

SELECT SUM(DATEDIFF(n, ACTM1.DATESTAMP, END_DATESTAMP_TABLE.END_DATESTAMP)) 
FROM INC     
LEFT OUTER JOIN ACTM1 ON INC.INCIDENT_NUMBER = ACTM1.NUMBER 
LEFT OUTER JOIN ACTA1 ON ACTM1.THENUMBER = ACTA1.THENUMBER 
LEFT OUTER JOIN (
    SELECT ACTM1_1.NUMBER, ACTM1_1.DATESTAMP AS END_DATESTAMP 
    FROM ACTM1 AS ACTM1_1 
    OUTER APPLY (
     SELECT ACTM1_1_1.NUMBER, /* MIN(ACTM1_1_1.THENUMBER) */ AS FOLLOWUP_THENUMBER 
     FROM ACTM1 AS ACTM1_1_1 
     WHERE (ACTM1_1_1.THENUMBER > ACTM1_1.THENUMBER) 
     AND (ACTM1_1.NUMBER = FOLLOWUP_THENUMBER_TABLE.NUMBER) 
     AND (ACTM1_1_1.[TYPE] IN ('Open', 'Status Change', 'Resolved', 'Closed')) 
    ) AS FOLLOWUP_THENUMBER_TABLE 
) AS END_DATESTAMP_TABLE ON ACTM1.NUMBER = END_DATESTAMP_TABLE.NUMBER 

顯然內部查詢裏面的MIN是沒有意義的，雖然。

Answer 2

我會重寫查詢根本不使用子查詢：

SELECT 
    SUM(DATEDIFF(n, A1.datestamp, A2.datestamp)) 

FROM 
    INC AS I 
INNER JOIN ACTM1 AS A1 ON 
    A1.number = INC.incident_number 
INNER JOIN ACTM1 AS A2 ON 
    A2.number > A1.number AND 
    A2.type IN ('Open', 'Status Change', 'Resolved', 'Closed') 
LEFT OUTER JOIN ACTM1 AS A3 ON 
    A3.number > A1.number AND 
    A3.type IN ('Open', 'Status Change', 'Resolved', 'Closed') AND 
    A3.number < A2.number 
WHERE 
    A3.number IS NULL 

我沒能完全的反向工程的語句。我不知道你是否需要左連接，我沒有看到ACTA1在哪裏被實際使用，所以我把它排除了。因此，您可能需要調整上述內容。總體思路是找到一個更大數字的行，它具有您需要的類型，但其中沒有其他行（A3）具有正確的類型和落在這兩個數字之間的數字。