SELECT 的情况 - 未返回预期结果

Question

如果 SC 中的 ContractID 出现在 AT_TMP_ 中，我尝试 return“Y”，如果没有出现，则尝试“N”。

这是我当前的代码 - 目前，“Y”是 returned 无论如何。

注意：T-SQL我很好，PL/SQL& Oracle 对我来说还是比较新

WITH AT_TMP_ AS (
    SELECT CONTRACT_ID FROM SC_SERVICE_CONTRACT_CFV WHERE 
    EXISTS(
        SELECT 1 
        FROM SC_SRV_CONTRACT_INVPLN_cfv cs 
        WHERE SC_SERVICE_CONTRACT_cfv.CONTRACT_ID = cs.contract_id 
        AND cs.cf$_invoice_date is null 
        AND CS.CF$_INV_NOT_REQ_DB = 'FALSE'
        ))
    
    SELECT SC.CONTRACT_ID, CASE
        WHEN
            SC.CONTRACT_ID IS NOT NULL THEN 'Y'
            ELSE 'N'
        END AS YES_NO
        FROM SC_SERVICE_CONTRACT_cfv SC
        
        LEFT OUTER JOIN 
            AT_TMP_
        ON AT_TMP_.Contract_ID = SC.Contract_ID;

Answer 1

您需要在AT_TMP_中完成案例。 SC 永远不会为空，因为它位于左联接的左侧。 AT_TMP 可以为空，因为它位于左联接的右侧。

WITH AT_TMP_ AS (
    SELECT CONTRACT_ID FROM SC_SERVICE_CONTRACT_CFV WHERE 
    EXISTS(
        SELECT 1 
        FROM SC_SRV_CONTRACT_INVPLN_cfv cs 
        WHERE SC_SERVICE_CONTRACT_cfv.CONTRACT_ID = cs.contract_id 
        AND cs.cf$_invoice_date is null 
        AND CS.CF$_INV_NOT_REQ_DB = 'FALSE'
        ))
    
    SELECT SC.CONTRACT_ID, CASE
        WHEN
            AT_TMP_.CONTRACT_ID IS NOT NULL THEN 'Y'
            ELSE 'N'
        END AS YES_NO
        FROM SC_SERVICE_CONTRACT_cfv SC
        
        LEFT OUTER JOIN 
            AT_TMP_
        ON AT_TMP_.Contract_ID = SC.Contract_ID;

Answer 2

您的 case 表达式目前没有引用 at_tmp_；您进行了外部联接，但随后对该联接的结果不执行任何操作。您可以更改 case 表达式以检查 CTE 中的值，如 @banana_99 所示。

但您并不真的需要 CTE。可以直接使用exists检查：

SELECT SC.CONTRACT_ID,
  CASE
    WHEN EXISTS (
      SELECT null
      FROM SC_SRV_CONTRACT_INVPLN_cfv SCI 
      WHERE SCI.CONTRACT_ID = SC.contract_id 
      AND SCI.cf$_invoice_date is null 
      AND SCI.CF$_INV_NOT_REQ_DB = 'FALSE'
    )
    THEN 'Y' ELSE 'N' END AS YES_NO
FROM SC_SERVICE_CONTRACT_cfv SC;

Answer 3

我认为你需要 EXISTS 而不是 LEFT JOIN -

WITH AT_TMP_ AS ( SELECT CONTRACT_ID
                    FROM SC_SERVICE_CONTRACT_CFV
                   WHERE EXISTS(SELECT 1 
                                  FROM SC_SRV_CONTRACT_INVPLN_cfv cs 
                                 WHERE cs.CONTRACT_ID = cs.contract_id 
                                   AND cs.cf$_invoice_date is null 
                                   AND CS.CF$_INV_NOT_REQ_DB = 'FALSE')
                )
SELECT SC.CONTRACT_ID,
       CASE WHEN EXISTS (SELECT 1 FROM AT_TMP_
                          WHERE AT_TMP_.Contract_ID = SC.Contract_ID) THEN 'Y'
            ELSE 'N' END AS YES_NO
  FROM SC_SERVICE_CONTRACT_cfv SC;

SELECT 的情况 - 未返回预期结果

Case with SELECT - not returning expected results

sql

oracle

case