Question

我有两张桌子。账户ACC和FinancialTrans FT

FinancialTrans表如下：

AcctID  TransTypeCode   DateOfTrans
123     TOLL            2016-06-06 00:00:00.000
123     TOLL            2016-06-02 00:00:00.000
123     TOLL            2016-04-28 00:00:00.000
123     PYMT            2016-03-11 00:00:00.000
123     TOLL            2015-12-22 00:00:00.000
123     TOLL            2015-12-22 00:00:00.000

要求是：
如果任何账户在过去两年内没有'TOLL'或'PYMT'，则打印'Flag'

SELECT ACC.Field1
      ,ACC.Field2
      ,ACC.Field3
      ,ACC.Field4
      ,CASE WHEN  
        (SELECT Max(DateOfTrans) FROM FinanceTrans FT
         WHERE ACC.AccountID = FT.AcctID
               AND (TransTypeCode = 'TOLL' AND DateOfTrans >= DATEADD(year, -2, GETDATE()))
               AND (TransTypeCode = 'PYMT' AND DateOfTrans >= DATEADD(year, -2, GETDATE()))
             GROUP BY AcctID, TransTypeCode) IS NULL
        THEN 'Flag'
        ELSE ''
       AND AS NoNo_Flag

FROM Accounts ACC

WHERE Condition 1, Condition 2...

Answer 1

试试这个：

SELECT
    acc.*,
    CASE WHEN f.acctid IS NULL THEN 'flag' ELSE '' END AS flag_noTollOrPmt
FROM
    accounts acc LEFT OUTER JOIN
    (SELECT 
        AcctID, 
        MAX(DateOfTrans) AS max_dateOfTrans_TollOrPmt
    FROM 
        FinanceTrans 
    WHERE 
        DateOfTrans >= DATEADD(YEAR, -2, GETDATE()) AND
        TransTypeCode IN( 'TOLL' , 'PYMT') 
    GROUP BY 
        AcctID) f ON
    acc.acctid = f.acctid

Answer 2

您应该使用窗口功能。逻辑是查看两种事务类型的最大日期。然后该标志取决于与当前日期的关系。

select a.*,
       (case when max(case when transtype in ('TOLL', 'PYMT') then DateOfTrans end) over
                       (partition by acctid) >= dateadd(year, -2, getdate())
             then 0 else 1
        end) as flag
from accounts;

Answer 3

我可能误解了这个问题，在这种情况下我可以改进我的答案。您似乎只需要检查子查询中是否存在记录。那么到那个程度你真的需要做一个聚合吗？并且，尝试使用EXISTS：

SELECT ACC.Field1, ACC.Field2, ACC.Field3, ACC.Field4, 
       CASE WHEN NOT EXISTS
           (SELECT DateOfTrans 
            FROM FinanceTrans FT
            WHERE ACC.AccountID = FT.AcctID
                  AND (TransTypeCode = 'TOLL' AND DateOfTrans >= DATEADD(year, -2, GETDATE()))
                  AND (TransTypeCode = 'PYMT' AND DateOfTrans >= DATEADD(year, -2, GETDATE())))
       THEN 'Flag'
       ELSE ''
       END AS NoNo_Flag
FROM Accounts ACC
WHERE [*condition*]

Answer 4

所以这就是我解决这个问题的方法：

我为每个创建了一个单独的列，然后将这些详细信息存储在临时表中然后我使用条件从临时表中提取数据来创建标志。

我的代码如下：

SELECT ACC.Field1
      ,ACC.Field2
      ,ACC.Field3
      ,ACC.Field4
      ,(SELECT Max(DateOfTrans) FROM FinanceTrans FT
        WHERE ACC.AccountID = FT.AcctID
          AND TransTypeCode = 'TOLL'
        GROUP BY AcctID, TransTypeCode) LastTollDate
      ,(SELECT Max(DateOfTrans) FROM FinanceTrans FT
        WHERE ACC.AccountID = FT.AcctID
          AND TransTypeCode = 'PYMT'
        GROUP BY AcctID, TransTypeCode) LastPymtDate

INTO #Temp_Data

FROM Accounts ACC

WHERE Condition 1, Condition 2...



SELECT ACC.Field1
      ,ACC.Field2
      ,ACC.Field3
      ,ACC.Field4
      ,CASE WHEN LastTollDate >= DATEADD(year, -2, GETDATE())
        AND LastPymtDate >= DATEADD(year, -2, GETDATE())
        THEN 'Flag'
        ELSE ''
       END AS Flag

FROM #Temp_Data

如何检查具有多个条件的SQL CASE？

4 个答案: