主表：故障单表SP_PD_FAULT

从表：报障单表SP_PD_FAULT_REPORT

目的：通过故障单关联查询出该故障单的报障单号，且用逗号分隔显示为一列

SELECT A.*,B.FAULT_NOS,B.FAULT_REPORT_IDS
  FROM (SELECT *
          FROM (SELECT DISTINCT (F.ID) F_ID,F.*,O.FAULT_OCCUR_TIME,O.FAULT_ADDRESS,O.FAULT_DESC
                  FROM LCAM_SC.SP_PD_FAULT F,(SELECT A.FAULT_ID,A.FeedER_ID,A.PROVINCE_CODE,A.FAULT_REPORT_STATUS,A.FAULT_REPORT_FROM,A.FAULT_REPORT_NO,A.FAULT_ADDRESS,A.FeedER_NAME,A.SUBSTATION_ID,A.SUBSTATION_NAME,A.ORGANIZATION_ID,A.TEAM_ID,A.BUREAU_CODE,A.CS_WORKORDER_NO,A.FAULT_DESC,A.FAULT_REPORTER,B.FAULT_OCCUR_TIME
                          FROM LCAM_SC.SP_PD_FAULT_REPORT A,(SELECT FAULT_ID,MIN(FAULT_OCCUR_TIME) FAULT_OCCUR_TIME
                                  FROM LCAM_SC.SP_PD_FAULT_REPORT
                                 GROUP BY FAULT_ID) B
                         WHERE A.FAULT_ID = B.FAULT_ID
                           AND (A.IS_MERGE = '1' OR A.IS_MERGE IS NULL)
                           AND A.PROVINCE_CODE = '03'
                           AND B.FAULT_OCCUR_TIME BETWEEN
                               TO_DATE('2016-01-01 00:00','yyyy-mm-dd hh24:mi') AND
                               (TO_DATE('2017-08-02 00:00','yyyy-mm-dd hh24:mi'))) O
                 WHERE F.ID = O.FAULT_ID
                   AND F.PROVINCE_CODE IS NOT NULL
                   AND F.BUREAU_CODE IS NOT NULL
                   AND O.PROVINCE_CODE = '03'
                   AND F.FAULT_STATUS IN (2,3,4,5,6,7)
                   AND O.FAULT_OCCUR_TIME BETWEEN
                       TO_DATE('2016-01-01 00:00','yyyy-mm-dd hh24:mi') AND
                       TO_DATE('2017-08-02 00:00','yyyy-mm-dd hh24:mi'))) A,(SELECT TO_CHAR(WM_CONCAT(FAULT_REPORT_NO)) FAULT_NOS,TO_CHAR(WM_CONCAT(ID)) FAULT_REPORT_IDS,FAULT_ID
          FROM LCAM_SC.SP_PD_FAULT_REPORT
         GROUP BY FAULT_ID) B
 WHERE A.ID = B.FAULT_ID(+)

(SELECT TO_CHAR(WM_CONCAT(FAULT_REPORT_NO)) FAULT_NOS,
TO_CHAR(WM_CONCAT(ID)) FAULT_REPORT_IDS,
FAULT_ID
FROM LCAM_SC.SP_PD_FAULT_REPORT
GROUP BY FAULT_ID) B
WHERE A.ID = B.FAULT_ID(+)

但是：报错不存在的LOB值

出现这个错误很多时候是使用了wmsys.wm_concat的同时使用了group,distinct 或者union，本来两者没有问题，问题在于：

1.OracleDatabase 10g Enterprise Edition Release 10.2.0.5.0以后的版本wmsys.wm_concat查询出的是LOB类型

2.oralce的sql语句中若查询了LOB字段是不能使用distinct，union，和group by等关键字的。

改成在把关联查询写成子查询

SELECT A.*,(SELECT TO_CHAR(WM_CONCAT(FAULT_REPORT_NO))
          FROM LCAM_SC.SP_PD_FAULT_REPORT B
         WHERE A.ID = B.FAULT_ID) FAULT_NOS,(SELECT TO_CHAR(WM_CONCAT(ID))
          FROM LCAM_SC.SP_PD_FAULT_REPORT B
         WHERE A.ID = B.FAULT_ID) FAULT_REPORT_IDS
  FROM (SELECT DISTINCT (F.ID) F_ID,'yyyy-mm-dd hh24:mi')) A

外面包一层

SELECT A.*,
(SELECT TO_CHAR(WM_CONCAT(FAULT_REPORT_NO))
FROM LCAM_SC.SP_PD_FAULT_REPORT B
WHERE A.ID = B.FAULT_ID) FAULT_NOS,
(SELECT TO_CHAR(WM_CONCAT(ID))
FROM LCAM_SC.SP_PD_FAULT_REPORT B
WHERE A.ID = B.FAULT_ID) FAULT_REPORT_IDS
FROM (

把需要的连接字符串使用子查询查出来