多个内连接 - SQL

时间:2017-04-07 08:06:07

标签: sql sql-server

我有这个SQL请求但不起作用......我真的不知道为什么因为我开始使用SQL ...

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'

感谢您的帮助

1 个答案:

答案 0 :(得分:2)

您的选择陈述

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'

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,问题是WHERE子句,AND条件的多个组合CDR.CDR_LOC_CODECDR.CDR_TYPE。请尝试将AND替换为OR

<强>更新: 由于p1,p2,p3属于同一个表,因此要避免重复列,请尝试使用

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')

注意:运行上面的查询可能需要一段时间才能使用大表。您可能希望在WHERE子句中添加一些条件以进一步调整。此外,我们应该将WHERE子句放到子查询中,因为CDR_LOC_CODECDR_TYPE属于同一个表dbo.T_CDR_APPEL。同时为动态列TMP_COL选中Null或为空,以避免加入表ON '' = ''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