多個內部加入 - SQL

Question

我有這樣的SQL請求，但不工作...我真的不知道爲什麼，因爲我與SQL開始...

Select CDR.*, 
    p1.*, 
    p2.*, 
    p3.* 
From dbo.T_CDR_APPEL CDR 
    Inner Join dbo.POS As p1 On CDR.CDR_LOC_CODE = p1.Loc_Code And 
    CDR.CDR_LOC_CODE Like 'SC%VI%' And CDR.CDR_TYPE Like 'I%' 
    Inner Join dbo.POS As p2 On CDR.CDR_LAST_REDIR_NO = p2.Post_type And 
    CDR.CDR_LOC_CODE Like 'CCN%' And CDR.CDR_TYPE Like 'I' 
    Inner Join dbo.POS As p3 On CDR.CDR_LAST_REDIR_NO = p3.Backup_Number And 
    CDR.CDR_LOC_CODE Like 'VoiceMail%' And CDR.CDR_TYPE Like 'IF' 

感謝您的幫助

Answer 1

你的SELECT語句

Select CDR.*, 
    p1.*, 
    p2.*, 
    p3.* 
From dbo.T_CDR_APPEL CDR 
    Inner Join dbo.POS As p1 On CDR.CDR_LOC_CODE = p1.Loc_Code And 
    CDR.CDR_LOC_CODE Like 'SC%VI%' And CDR.CDR_TYPE Like 'I%' 
    Inner Join dbo.POS As p2 On CDR.CDR_LAST_REDIR_NO = p2.Post_type And 
    CDR.CDR_LOC_CODE Like 'CCN%' And CDR.CDR_TYPE Like 'I' 
    Inner Join dbo.POS As p3 On CDR.CDR_LAST_REDIR_NO = p3.Backup_Number And 
    CDR.CDR_LOC_CODE Like 'VoiceMail%' And CDR.CDR_TYPE Like 'IF' 

是基本相同

SELECT CDR.*, 
    p1.*, 
    p2.*, 
    p3.* 
FROM dbo.T_CDR_APPEL CDR 
    INNER JOIN dbo.POS AS p1 ON CDR.CDR_LOC_CODE = p1.Loc_Code 
    INNER JOIN dbo.POS AS p2 ON CDR.CDR_LAST_REDIR_NO = p2.Post_type 
    INNER JOIN dbo.POS AS p3 ON CDR.CDR_LAST_REDIR_NO = p3.Backup_Number 
WHERE 
    CDR.CDR_LOC_CODE LIKE 'SC%VI%' AND  
    CDR.CDR_LOC_CODE LIKE 'CCN%' AND 
    CDR.CDR_LOC_CODE LIKE 'VoiceMail%' AND 
    CDR.CDR_TYPE LIKE 'I%' AND 
    CDR.CDR_TYPE LIKE 'I' AND 
    CDR.CDR_TYPE LIKE 'IF' 

因此，問題是WHERE子句與CDR.CDR_LOC_CODE和CDR.CDR_TYPE相同的列的AND條件的許多組合。請嘗試用OR代替AND。

更新： 由於p1,p2,p3是相同的表，避免重複列，試試這個

SELECT CDR.*, p.* FROM 
(
    SELECT *, 
    (CASE 
     WHEN CDR_TYPE LIKE 'I%' THEN CDR_LOC_CODE 
     WHEN CDR_TYPE LIKE 'I' THEN CDR_LAST_REDIR_NO 
     WHEN CDR_TYPE LIKE 'IF' THEN CDR_LAST_REDIR_NO 
     ELSE '' 
    END) TMP_COL FROM dbo.T_CDR_APPEL 
) CDR 
INNER JOIN dbo.POS p ON 
    (CASE 
     WHEN CDR.CDR_TYPE LIKE 'I%' THEN p.Loc_Code 
     WHEN CDR.CDR_TYPE LIKE 'I' THEN p.Post_type 
     WHEN CDR.CDR_TYPE LIKE 'IF' THEN p.Backup_Number 
     ELSE '' 
    END) = CDR.TMP_COL 
WHERE 
    (CDR.CDR_LOC_CODE LIKE 'SC%VI%' AND CDR.CDR_TYPE LIKE 'I%') OR 
    (CDR.CDR_LOC_CODE LIKE 'CCN%' AND CDR.CDR_TYPE LIKE 'I') OR 
    (CDR.CDR_LOC_CODE LIKE 'VoiceMail%' AND CDR.CDR_TYPE LIKE 'IF') 

注：運行上述查詢可能需要一段時間與大表。您可能需要爲WHERE子句添加一些條件以進一步調整。我們還應該把WHERE子句放到子查詢中，因爲CDR_LOC_CODE和CDR_TYPE與dbo.T_CDR_APPEL是同一個表。另外，請檢查動態列TMP_COL的空值或空值，以避免連接表ON '' = ''或ON NULL = NULL。

SELECT CDR.*, p.* FROM 
(
    SELECT *, 
    (CASE 
     WHEN CDR_TYPE LIKE 'I%' THEN CDR_LOC_CODE 
     WHEN CDR_TYPE LIKE 'I' THEN CDR_LAST_REDIR_NO 
     WHEN CDR_TYPE LIKE 'IF' THEN CDR_LAST_REDIR_NO 
     ELSE '' 
    END) TMP_COL FROM dbo.T_CDR_APPEL 
    WHERE 
     (CDR_LOC_CODE LIKE 'SC%VI%' AND CDR_TYPE LIKE 'I%') OR 
     (CDR_LOC_CODE LIKE 'CCN%' AND CDR_TYPE LIKE 'I') OR 
     (CDR_LOC_CODE LIKE 'VoiceMail%' AND CDR_TYPE LIKE 'IF') 
) CDR 
INNER JOIN dbo.POS p ON 
    (CASE 
     WHEN CDR.CDR_TYPE LIKE 'I%' THEN p.Loc_Code 
     WHEN CDR.CDR_TYPE LIKE 'I' THEN p.Post_type 
     WHEN CDR.CDR_TYPE LIKE 'IF' THEN p.Backup_Number 
     ELSE '' 
    END) = CDR.TMP_COL AND NULLIF(CDR.TMP_COL, '') IS NOT NULL