Sql 在下面的查询中，ACCOUNT\u CHECKER\u EXIT datetime变为null

在下面的查询结果中，ACCOUNT\u CHECKER\u EXIT datetime返回空值

SELECT WI_NAME,
    PREVIOUSWORKSTEP,
    CURRENTWORKSTEP,
    PREV_TO_PREV_WORKSTEP,
    LEAD_ID,
    MDM_ID,
    SOURCE_BRANCH_NAME,
    OPENING_BRANCH_NAME,
    SOURCE_BRANCH_ID,
    OPENING_BRANCH_ID,
    APP_FORM_DATE,
    ACKN_DATE,
    PROD_OPT,
    SA_BASE_PROD_TYPE,
    SA_PROD_CODE,
    SA_PROD_NAME,
    SA_ACCOUNT_NO,
    SA_ACC_TYPE,
    SA_PROCESSING_TYPE,
    SA_DECISION,
    CA_BASE_PROD_TYPE,
    CA_PROD_CODE,
    CA_PROD_NAME,
    CA_ACCOUNT_NO,
    CA_ACC_TYPE,
    CA_PROCESSING_TYPE,
    CA_DECISION,
    LKR_DECISION,
    CUST_NAME,
    CUST_AC_NO,
    CUST_ID,
    CONTACT_NO,
   CUST_TYPE,
    CUST_CATEGORY,
    SME,
    CPH_FLAG,
    FATCA_APPLICABLE,
    FATCA_ANNEXURE,
    BARCODE,
    PARTNER_SEGMENT,
    BUSS_SEGMENT,
    SERVICE_RM_CODE,
    SALES_RM_CODE,
    SOURCING_RM_CODE,
    FUNDING_MODE,
    FUNDING_AMT,
    CHEQUE_DATE,
    CHEQUE_NO,
    UNQ_RF_NO,
    CRP,
    PAN_NO,
    MOBILE_NO,
    DECISION,
    SCANNING_DECISION,
    NOC_CODE,
    PRIORITY,
    CHANNEL_TYPE,
    PARENTWORKITEM_ID,
    CPH_CODE,
    IS_PARENT,
    TD_PRODUCT_CODE,
    PROCESSING_FLAG,
    CASE_PICKUP_DATE_TIME,
    MICR_CODE,
    RM_NAME,
    Rm_Emailid,
    Rm_Mobile,
    max(Initiation) Initiation,
    Max(ACCOUNT_CHECKER_EXIT) ACCOUNT_CHECKER_EXIT
    From 
    (
    SELECT a.WI_NAME,
    a.PREVIOUSWORKSTEP,
    a.CURRENTWORKSTEP,
    a.PREV_TO_PREV_WORKSTEP,
    a.LEAD_ID,
    a.MDM_ID,
    a.SOURCE_BRANCH_NAME,
    a.OPENING_BRANCH_NAME,
    a.SOURCE_BRANCH_ID,
    a.OPENING_BRANCH_ID,
    a.APP_FORM_DATE,
    a.ACKN_DATE,
    a.PROD_OPT,
    a.SA_BASE_PROD_TYPE,
    a.SA_PROD_CODE,
    a.SA_PROD_NAME,
    a.SA_ACCOUNT_NO,
    a.SA_ACC_TYPE,
    a.SA_PROCESSING_TYPE,
    a.SA_DECISION,
    a.CA_BASE_PROD_TYPE,
    a.CA_PROD_CODE,
    a.CA_PROD_NAME,
    a.CA_ACCOUNT_NO,
    a.CA_ACC_TYPE,
    a.CA_PROCESSING_TYPE,
    a.CA_DECISION,
    a.LKR_DECISION,
    a.CUST_NAME,
    a.CUST_AC_NO,
    a.CUST_ID,
    a.CONTACT_NO,
    a.CUST_TYPE,
    a.CUST_CATEGORY,
    a.SME,
    a.CPH_FLAG,
    a.FATCA_APPLICABLE,
    a.FATCA_ANNEXURE,
    a.BARCODE,
    a.PARTNER_SEGMENT,
    a.BUSS_SEGMENT,
    a.SERVICE_RM_CODE,
    a.SALES_RM_CODE,
    A.SOURCING_RM_CODE,
    a.FUNDING_MODE,
    a.FUNDING_AMT,
    a.CHEQUE_DATE,
    a.CHEQUE_NO,
    a.UNQ_RF_NO,
    a.CRP,
    a.PAN_NO,
    a.MOBILE_NO,
    a.DECISION,
    a.SCANNING_DECISION,
    a.NOC_CODE,
    a.PRIORITY,
    a.CHANNEL_TYPE,
    a.PARENTWORKITEM_ID,
    a.CPH_CODE,
    a.IS_PARENT,
    a.TD_PRODUCT_CODE,
    a.PROCESSING_FLAG,
    A.Case_Pickup_Date_Time,
    a.MICR_CODE,
    A.Rm_Name,
    A.Rm_Emailid,
    A.Rm_Mobile,
    (
        Case
          WHEN WORKSTEPNAME='Case_Initiation'
          THEN Case_Submitted_Datetime
        END) initiation,
        (
        Case
          WHEN WORKSTEPNAME='Account_Checker' and b.decision='Account Opened'
          Then Case_Submitted_Datetime
        END) ACCOUNT_CHECKER_EXIT
   -- B.Introductiondatetime
   From abc_table A,  

   (Select Processinstanceid,Case_Submitted_Datetime,Workstepname, Decision From abcdefgh Union 
   Select Processinstanceid,Case_Submitted_Datetime, Workstepname, Decision From abcdefgh_H
   )B

   Where A.Wi_Name =B.Processinstanceid And A.Currentworkstep<>'Discard1'-- and b.Case_Submitted_Datetime Between To_Char(To_Date('2020-01-01', 'yyyy-mm-dd'), 'dd-MON-yyyy') And  To_Char(To_Date('2020-02-15', 'yyyy-mm-dd'), 'dd-MON-yyyy') 
   )

   Where Trunc(Initiation) Between To_Char(To_Date('2019-01-01', 'yyyy-mm-dd'), 'dd-MON-yyyy') And  To_Char(To_Date('2020-02-15', 'yyyy-mm-dd'), 'dd-MON-yyyy')

   GROUP BY WI_NAME, PREVIOUSWORKSTEP, CURRENTWORKSTEP, PREV_TO_PREV_WORKSTEP, LEAD_ID, MDM_ID, SOURCE_BRANCH_NAME, OPENING_BRANCH_NAME, SOURCE_BRANCH_ID, OPENING_BRANCH_ID, APP_FORM_DATE, ACKN_DATE, PROD_OPT, SA_BASE_PROD_TYPE, SA_PROD_CODE, SA_PROD_NAME, SA_ACCOUNT_NO, SA_ACC_TYPE, SA_PROCESSING_TYPE, SA_DECISION, CA_BASE_PROD_TYPE, CA_PROD_CODE, CA_PROD_NAME, CA_ACCOUNT_NO, CA_ACC_TYPE, CA_PROCESSING_TYPE, CA_DECISION, LKR_DECISION, CUST_NAME, CUST_AC_NO, CUST_ID, CONTACT_NO, CUST_TYPE, CUST_CATEGORY, SME, CPH_FLAG, FATCA_APPLICABLE, FATCA_ANNEXURE, BARCODE, PARTNER_SEGMENT, BUSS_SEGMENT, SERVICE_RM_CODE, SALES_RM_CODE, SOURCING_RM_CODE, FUNDING_MODE, FUNDING_AMT, CHEQUE_DATE, CHEQUE_NO, UNQ_RF_NO, CRP, PAN_NO, MOBILE_NO, DECISION, SCANNING_DECISION, NOC_CODE, PRIORITY, CHANNEL_TYPE, PARENTWORKITEM_ID, CPH_CODE, IS_PARENT, TD_PRODUCT_CODE, PROCESSING_FLAG, CASE_PICKUP_DATE_TIME, MICR_CODE, RM_NAME, Rm_Emailid, Rm_Mobile;

所以根据这条线,

case when WORKSTEPNAME='Account_Checker' and b.decision='Account Opened'
     then Case_Submitted_Datetime end ACCOUNT_CHECKER_EXIT

可以肯定地说，当WORKSTEPNAME='Account\u Checker'和b.decision='Account Opened'时，此行不符合条件。在case语句中，当所有case都已计算且不匹配，并且没有else子句时，返回值为null

---

请参见

您是否可以共享一些具有2个3个值的数据，并仅使用maxACCOUNT\u CHECKER\u EXIT进行测试？如果没有更多的信息，我们无法帮助您处理这样的请求。也请分享你的描述表。