Question

我有一个包含多个日期的多个记录的表。

我试图看到“日期1”和“日期2”之间的区别，而我的完整外部联接并没有返回我期望的数据。

我知道日期1有13278行，日期2有13282 - 因此我希望看到至少13282行，但我回到13195 ...这是INNER JOIN（我测试了这个）

我希望结果如下：

001     000123    009    NULL    1000
001     000124    009    1000    1000
001     000125    009    1000    1000
001     000126    009    1000    NULL

但这不会从任何一方获得任何空行？

SELECT 
    COALESCE(c.AccountBranch, p.AccountBranch)
    , COALESCE(c.AccountNumber, p.AccountNumber)
    , COALESCE(c.AccountSuffix, p.AccountSuffix)
    , c.PrincipleAmount
    , p.PrincipleAmount
    FROM ADStaging..cb_account_extension_principle_dpd c
    FULL OUTER JOIN ADStaging..cb_account_extension_principle_dpd p
        ON p.AccountBranch = c.AccountBranch
        AND p.AccountNumber = c.AccountNumber
        AND p.AccountSuffix = c.AccountSuffix
WHERE 
    (c.BusinessDataDate IS NULL OR c.BusinessDataDate = @CurrentBusinessDataDate)
    AND
    (p.BusinessDataDate IS NULL OR p.BusinessDataDate = @PreviousBusinessDataDate)

这有效 - 在两个单独的选择语句中将连接的“键”组合在一起？

SELECT
      COALESCE(C.Account, P.Account) AS Account
    , COALESCE(C.AccountBranch, P.AccountBranch) as AccountBranch
    , COALESCE(C.AccountNumber, P.AccountNumber) as AccountNumber
    , COALESCE(C.AccountSuffix, P.AccountSuffix) as AccountSuffix
    , P.PrincipleAmount AS PreviousAmount
    , C.PrincipleAmount AS CurrentAmount
    , ISNULL(C.PrincipleAmount, P.PrincipleAmount) - ISNULL(P.PrincipleAmount,0)
FROM 
(SELECT 
    (pd.AccountBranch + pd.AccountNumber + pd.AccountSuffix) AS Account
    , pd.AccountBranch
    , pd.AccountNumber
    , pd.AccountSuffix
    , pd.PrincipleAmount
FROM ADStaging..cb_account_extension_principle_dpd pd
WHERE pd.BusinessDataDate = @CurrentBusinessDataDate) C
FULL OUTER JOIN 
(SELECT 
    (pd.AccountBranch + pd.AccountNumber + pd.AccountSuffix) AS Account
    , pd.AccountBranch
    , pd.AccountNumber
    , pd.AccountSuffix
    , pd.PrincipleAmount
FROM ADStaging..cb_account_extension_principle_dpd pd
WHERE pd.BusinessDataDate = @PreviousBusinessDataDate) P
    ON P.Account = C.Account
WHERE 
    (P.PrincipleAmount IS NULL OR C.PrincipleAmount IS NULL)
    OR
    P.PrincipleAmount <> C.PrincipleAmount

但这不是 - 加入组合值 - 只有当它们是单独的表时才会出现？

SELECT 
    COALESCE(c.AccountBranch, p.AccountBranch)
    , COALESCE(c.AccountNumber, p.AccountNumber)
    , COALESCE(c.AccountSuffix, p.AccountSuffix)
    , c.PrincipleAmount
    , p.PrincipleAmount
    FROM ADStaging..cb_account_extension_principle_dpd c
    FULL OUTER JOIN ADStaging..cb_account_extension_principle_dpd p
        ON (p.AccountBranch + p.AccountNumber + p.AccountSuffix)
        = (c.AccountBranch + c.AccountNumber + c.AccountSuffix)
WHERE 
    (c.BusinessDataDate = @CurrentBusinessDataDate)
    AND
    (p.BusinessDataDate = @PreviousBusinessDataDate)

Answer 1

杀死外部联接的位置列不能同时为null，也不能为值将条件放在连接中。

SELECT COALESCE(c.AccountBranch, p.AccountBranch)
     , COALESCE(c.AccountNumber, p.AccountNumber)
     , COALESCE(c.AccountSuffix, p.AccountSuffix)
     , c.PrincipleAmount, p.PrincipleAmount
FROM            cb_account_extension_principle_dpd c
FULL OUTER JOIN cb_account_extension_principle_dpd p
  ON p.AccountBranch = c.AccountBranch
 AND p.AccountNumber = c.AccountNumber 
 AND p.AccountSuffix = c.AccountSuffix
 AND c.BusinessDataDate = @CurrentBusinessDataDate
 AND p.BusinessDataDate = @PreviousBusinessDataDate

Answer 2

我认为您的问题是，在第一个查询中，日期不是匹配的一部分。在您的第二个查询中，您加入的两个集合已经过日期过滤，因此它模仿了您在日期匹配时会发生什么。假设您拥有相同的accountbranch，数字，后缀两次但不同的日期！这意味着完整的外部联接找到匹配项，因为您在ON子句中没有日期。

试试这个：

use ADStaging;
--your dates go here:
declare @CurrentBusinessDataDate date = '2013-04-21'
, @PreviousBusinessDataDate date = '2013-04-23';
SELECT 
COALESCE(c.AccountBranch, p.AccountBranch)
, COALESCE(c.AccountNumber, p.AccountNumber)
, COALESCE(c.AccountSuffix, p.AccountSuffix)
, c.PrincipleAmount
, p.PrincipleAmount

FROM cb_account_extension_principle_dpd AS c
FULL OUTER JOIN cb_account_extension_principle_dpd AS p
    ON p.AccountBranch = c.AccountBranch
    AND p.AccountNumber = c.AccountNumber
    AND p.AccountSuffix = c.AccountSuffix
    AND p.BusinessDataDate = @PreviousBusinessDataDate
    AND c.BusinessDataDate = @CurrentBusinessDataDate;

全外连接不返回所有行？

2 个答案: