ORA-01427: 单行子查询返回多于一行 ,,WHEN USING SELECT COUNT

Posted 2023-05-08

【中文标题】ORA-01427: 单行子查询返回多于一行 ,,WHEN USING SELECT COUNT

【英文标题】：ORA-01427: single-row subquery returns more than one row ,,WHEN USING SELECT COUNT

【发布时间】：2014-07-01 09:44:03

【问题描述】：

我有这两个查询，两者都是相同的，但第一行的区别，第一个语句计算结果，另一个得到行， 问题是它得到了行并且无法计算它们

第一个查询出错（ORA-01427：单行子查询返回多行）

第一个（计数行）

    SELECT  COUNT(*) FROM (
      SELECT A.* , 
      SUBSTR(A.RECORD_DATE,9,4) RECORD_NOTICE_TIME , 
      (SELECT B.CLOSE_FLAG FROM HARAM.NOTICES_DEPT B WHERE B.NOTICE_SN = A.NOTICE_SN AND B.DEPT_ID = 116 AND B.RECORD_STATUS <> 3) CLOSE_FLAG , 
      (SELECT DEPARTMENT_ID FROM HARAM.EMPLOYES WHERE PERSONAL_CODE =A.NOTICE_USER) NOTICE_USER_DEPT , 
      (SELECT SUBSTR(ND.CREATION_TIMESTAMP,9,4) TRANS_NOTICE_TIME FROM HARAM.NOTICES_DEPT ND WHERE ND.NOTICE_SN = A.NOTICE_SN AND ND.RECORD_STATUS != 3 AND ND.DEPT_ID = 116 ) TRANS_NOTICE_TIME,
      (SELECT  (SELECT DEPARTMENT_NAME FROM HARAM.DEPARTMENT WHERE DS.SECTION_ID=DEPARTMENT_ID) FROM HARAM.NOTICES_DEPT_SECTIONS DS WHERE DS.NOTICE_SN=A.NOTICE_SN) SECTION_NAME 
      FROM HARAM.NOTICES A 
      WHERE EXISTS (SELECT NULL FROM HARAM.NOTICES_DEPT C WHERE C.NOTICE_SN = A.NOTICE_SN AND C.RECORD_STATUS <> 3 AND C.DEPT_ID = 116 ) AND A.RECORD_STATUS <> 3 
    ) 
    WHERE NOTICE_STATUS != 5 AND RECORD_STATUS <> 3 AND CLOSE_FLAG=3 AND SECTION_NAME IS NOT NULL
    ORDER BY CLOSE_FLAG DESC , CREATION_TIMESTAMP DESC;

第二个（获取行）

    SELECT * FROM (
      SELECT A.* , 
      SUBSTR(A.RECORD_DATE,9,4) RECORD_NOTICE_TIME , 
      (SELECT B.CLOSE_FLAG FROM HARAM.NOTICES_DEPT B WHERE B.NOTICE_SN = A.NOTICE_SN AND B.DEPT_ID = 116 AND B.RECORD_STATUS <> 3) CLOSE_FLAG , 
      (SELECT DEPARTMENT_ID FROM HARAM.EMPLOYES WHERE PERSONAL_CODE =A.NOTICE_USER) NOTICE_USER_DEPT , 
      (SELECT SUBSTR(ND.CREATION_TIMESTAMP,9,4) TRANS_NOTICE_TIME FROM HARAM.NOTICES_DEPT ND WHERE ND.NOTICE_SN = A.NOTICE_SN AND ND.RECORD_STATUS != 3 AND ND.DEPT_ID = 116 ) TRANS_NOTICE_TIME, 
      (SELECT (SELECT DEPARTMENT_NAME FROM HARAM.DEPARTMENT WHERE DS.SECTION_ID=DEPARTMENT_ID) FROM HARAM.NOTICES_DEPT_SECTIONS DS WHERE DS.NOTICE_SN=A.NOTICE_SN) SECTION_NAME 
      FROM HARAM.NOTICES A  
      WHERE EXISTS (SELECT NULL FROM HARAM.NOTICES_DEPT C WHERE C.NOTICE_SN = A.NOTICE_SN AND C.RECORD_STATUS <> 3 AND C.DEPT_ID = 116 ) AND A.RECORD_STATUS <> 3 
    ) 
    WHERE NOTICE_STATUS != 5 AND RECORD_STATUS <> 3 AND CLOSE_FLAG=3 AND SECTION_NAME IS NOT NULL
    ORDER BY CLOSE_FLAG DESC,CREATION_TIMESTAMP DESC;

【问题讨论】：

有意思，你用的是什么版本的Oracle？此错误可能来自内部 SELECT 子句中的 sub-select，与外部 SELECT

无关

你是对的，错误出现在（SELECT (SELECT DEPARTMENT_NAME FROM HARAM.DEPARTMENT WHERE DS.SECTION_ID=DEPARTMENT_ID) FROM HARAM.NOTICES_DEPT_SECTIONS DS WHERE DS.NOTICE_SN=A.NOTICE_SN）SECTION_NAME 但如何我解决了吗？

【参考方案1】：

您可能需要将您的INNER Select 替换为以下之一。我将其转换为Join 并使用ROWNUM < =1 将行数限制为最多1。

(SELECT
  D.DEPARTMENT_NAME
FROM HARAM.NOTICES_DEPT_SECTIONS DS, HARAM.DEPARTMENT D
WHERE DS.NOTICE_SN=A.NOTICE_SN
 AND DS.SECTION_ID=D.DEPARTMENT_ID
 AND ROWNUM <= 1
) SECTION_NAME