Question

我正在处理需要帮助的DB2 Query。如果有人愿意看一看，我真的很感激。

以下查询是我目前所做的：

SELECT
 C.CONTROL_NO,
    NR.NOTICE_CODE,
    COALESCE(C.LNAME,'') AS LNAME,
    COALESCE(C.FNAME,'') AS FNAME,
 CASE
    WHEN SOC_SEC_NO IS NULL THEN ''
       WHEN SOC_SEC_NO IS NOT NULL THEN REPLACE(SOC_SEC_NO, LEFT(SOC_SEC_NO,5) , '*****')
    END AS SOC_SEC_NO,
    COALESCE(C.SOC_SEC_NO, '') AS SOC_SEC_NO_FULL,
    COALESCE(C.EMPLOYER,'') AS EMPLOYER,
    COALESCE(C.FED_EMP_NO, '') AS FED_EMP_NO,
    COALESCE(CAST(C.STW_DATE AS VARCHAR(10)),'') AS STW_DATE,
    COALESCE(CAST(C.CREATE_DTE AS VARCHAR(10)),'') AS CREATE_DTE,
    CASE WHEN C.STATUS IS NULL THEN ''
       WHEN C.STATUS = 'CER - CERTIFIED' THEN 'CERTIFIED'
       WHEN C.STATUS = 'DEF - DEFICIENT' THEN 'DEFICIENT'
       WHEN C.STATUS = 'DEN - DENIED' THEN 'DENIED'
       WHEN C.STATUS = 'D90 - DENIED(OVER 90 DAYS OLD)' THEN 'DENIED(OVER 90 DAYS OLD)'
       WHEN C.STATUS = 'EPA - POA EXPIRED' THEN 'POA EXPIRED'
       WHEN C.STATUS = 'EXP - EXPIRED REQUEST' THEN 'EXPIRED REQUEST'
       WHEN C.STATUS = 'MAN - MANUAL' THEN 'MANUAL'
       WHEN C.STATUS = 'NAR - NON ACTIONABLE REQUEST' THEN 'NON ACTIONABLE REQUEST'
       WHEN C.STATUS = 'NPA - POA NOT FOUND' THEN 'POA NOT FOUND'
       WHEN C.STATUS = 'NPC - PENDING CERT/NO POA' THEN 'PENDING CERT/NO POA'
       WHEN C.STATUS = 'NPD - PENDING DENY/NO POA' THEN 'PENDING DENY/NO POA'
       WHEN C.STATUS = 'OOS - OOS VALIDATION' THEN 'OOS VALIDATION'
       WHEN C.STATUS = 'OTG - OTHER TARGET GROUPS' THEN 'OTHER TARGET GROUPS'
       WHEN C.STATUS = 'PEN - PENDING VALIDATION' THEN 'PENDING VALIDATION'
       WHEN C.STATUS = 'RTV - READY TO VALIDATE' THEN 'READY TO VALIDATE'
    END AS STATUS,
    CASE
    WHEN C.WOTC_AWARD_CODE IS NULL AND WTW_AWARD_CODE IS NULL THEN ''
    WHEN CONCAT(C.WOTC_AWARD_CODE, C.WTW_AWARD_CODE) = 'A  ' THEN 'A - SHORT-TERM TANF RECIPIENT' 
    WHEN CONCAT(C.WOTC_AWARD_CODE, C.WTW_AWARD_CODE) = 'B  ' THEN 'B - VETERANS' 
       WHEN CONCAT(C.WOTC_AWARD_CODE, C.WTW_AWARD_CODE) = 'BA ' THEN 'BA - QUALIFIED VET RECEIVING SNAP BENEFITS'
       WHEN CONCAT(C.WOTC_AWARD_CODE, C.WTW_AWARD_CODE) = 'BB ' THEN 'BB - DISABLED VET'  
       WHEN CONCAT(C.WOTC_AWARD_CODE, C.WTW_AWARD_CODE) = 'BC ' THEN 'BC - DISABLED VET UNEMPLOYED FOR 6 MONTHS' 
       WHEN CONCAT(C.WOTC_AWARD_CODE, C.WTW_AWARD_CODE) = 'BD ' THEN 'BD - VET UNEMPLOYED FOR 4 WEEKS BUT LESS THAN 6 MONTHS' 
       WHEN CONCAT(C.WOTC_AWARD_CODE, C.WTW_AWARD_CODE) = 'BE ' THEN 'BE - VET UNEMPLOYED FOR 6 MONTH' 
       WHEN CONCAT(C.WOTC_AWARD_CODE, C.WTW_AWARD_CODE) = 'C  ' THEN 'C - EX-FELON' 
       WHEN CONCAT(C.WOTC_AWARD_CODE, C.WTW_AWARD_CODE) = 'D  ' THEN 'D - DESIGNATED COMMUNITY RESIDENT' 
       WHEN CONCAT(C.WOTC_AWARD_CODE, C.WTW_AWARD_CODE) = 'E  ' THEN 'E - VOCATIONAL REHABILITATION REFERRAL' 
       WHEN CONCAT(C.WOTC_AWARD_CODE, C.WTW_AWARD_CODE) = 'F  ' THEN 'F - SUMMER YOUTH' 
       WHEN CONCAT(C.WOTC_AWARD_CODE, C.WTW_AWARD_CODE) = 'G  ' THEN 'G - SNAP (FOOD STAMP) RECIPIENT' 
       WHEN CONCAT(C.WOTC_AWARD_CODE, C.WTW_AWARD_CODE) = 'H  ' THEN 'H - SUPPLEMENTAL SECURITY INCOME (SSI) RECIPIENT' 
       WHEN CONCAT(C.WOTC_AWARD_CODE, C.WTW_AWARD_CODE) = '  I' THEN 'I - LONG-TERM TANF RECIPIENT' 
       WHEN CONCAT(C.WOTC_AWARD_CODE, C.WTW_AWARD_CODE) = 'J  ' THEN 'J - UNEMPLOYED VETERAN' 
       WHEN CONCAT(C.WOTC_AWARD_CODE, C.WTW_AWARD_CODE) = 'K  ' THEN 'K - DISCONNECTED YOUTH' 
    END AS WOTC_AWARD_CODE,  
 CASE
    WHEN C.STATUS IN ('CER - CERTIFIED', 'DEF - DEFICIENT', 'DEN - DENIED', 'D90 - DENIED(OVER 90 DAYS OLD)', 'EXP - EXPIRED REQUEST', 'NAR - NON ACTIONABLE REQUEST')
          THEN COALESCE(CAST(NR.NOTICE_DT AS VARCHAR(10)), '')
       ELSE ''
 END AS NOTICE_DT
FROM WITC00DS.DB2CUST C
LEFT OUTER JOIN WITC00DS.NOTIFICATION_REQUE NR
 ON C.CONTROL_NO = NR.CONTROL_NBR 
WHERE
 C.AGENT_CODE = 'HR'
AND C.STW_DATE BETWEEN '01/01/2000' AND '01/21/2014' 
AND (
   (NR.NOTICE_DT = (SELECT MAX(NOTICE_DT) FROM WITC00DS.NOTIFICATION_REQUE ZZ WHERE ZZ.CONTROL_NBR = C.CONTROL_NO AND NOTICE_CODE IN ('C', 'F', 'D', 'D2', 'XP', 'S', 'VR'))
      OR (NR.NOTICE_DT IS NULL))
 )
AND
   ((NOTICE_CODE IN ('C', 'F', 'D', 'D2', 'XP', 'S', 'VR') 
   ) OR (NR.NOTICE_DT IS NULL))
ORDER BY Control_No

可以看出，这个查询基本上在两个表之间进行左外连接：两个表中控件号列的DB2CUST和NOTIFICATION_REQUE。

此查询非常接近我的需要但是在极少数情况下，我在结果中获得重复控制号记录，其中最大通知日期相等。在通知日期相同的少数情况下，我只需要选择符合以下条件的一个：

如果DB2CUST中的状态=＆＃39;缺乏＆＃39;和notice_code =＆＃39; F＆＃39;选择记录
如果DB2CUST中的状态=＆＃39;拒绝＆＃39;和notice_code = ＆＃39; d＆＃39;选择该记录
如果DB2CUST中的状态=＆＃39;认证＆＃39;和 notice_code =＆＃39; C＆＃39;选择该记录等。

因此，在极少数情况下，存在重复的最大通知日期，我需要根据上面显示的状态和通知代码的正确组合选择两个记录中的一个。有人可以帮我增强我目前要做的查询吗？

谢谢，

皮特

Answer 1

您可以使用row_number()获得所需内容。以下是您可以执行的操作的示例：

with cte (<your query here>)
select cte.*
from (select cte.*,
             row_number() over (partition by CONTROL_NO order by
                                (case when DB2CUST.status = 'Deficient' and notice_code = 'F' then 1
                                      when DB2CUST.status = 'Denied' and notice_code = 'D' then 2
                                      when DB2CUST.status = 'Certified' and notice_code = 'C' then 3
                                      . . .
                                 end)
                                ) as seqnum

      from cte
     ) t
where seqnum = 1;

Answer 2

感谢您的帮助。对此，我真的非常感激。我能够让它运行，但不得不做一些小的改动。最终结果如下所示：

WITH CTE AS  
( <My Query> )
    SELECT * FROM 
    (
   SELECT  CTE.*, ROW_NUMBER() OVER 
    (
      PARTITION BY CONTROL_NO ORDER BY 
      (
         CASE 
            WHEN STATUS = 'Deficient' AND NOTICE_CODE = 'F' THEN 1 
            WHEN STATUS = 'Denied' AND NOTICE_CODE = 'D' THEN 2 
            WHEN STATUS = 'Certified' AND NOTICE_CODE = 'C' THEN 3 
         END
      ) 
   ) AS SEQNUM
   FROM CTE 
) T  
WHERE SEQNUM = 1

另外，我想知道如何通过Control_No对结果DESCENDING进行排序？再次感谢您的帮助。

皮特

需要DB2 SQL Query的帮助

2 个答案: