Oracle 18c

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CREATE TABLE dt
  (bmb_id integer NOT NULL,
   pole_j CLOB CONSTRAINT ensure_json CHECK (pole_j IS JSON));
insert into dt (bmb_id,pole_j) values (1,'{
  "principalsAndManagement": {
    "currentPrincipal": [
      {
        "principalName": {
          "fullName": "xxx xxx"
        },
        "politicallyExposedPersons": [
          {
            "primaryName": "Andrzej Jankowski",
            "entityMatchScore": 92,
            "supplierRiskScore": 90,
            "personDetail": {
              "entityTypeText": "Person",
              "eventDetail": [
                {
                  "eventTypeText": "PEP",
                  "eventSubTypeText": "ASC",
                  "eventText": [
                    "On List [PEP Connect - Poland]"
                  ],
                  "eventDate": "2017-06-21"
                }
              ],
              "name": {
                "primaryName": "xxxxxx",
                "knownByName": 0
              }
            }
          }
        ]
      }
    ]
  }
}')
1 rows affected

SELECT
"fullNameP",
"eventTypeText",
listagg('type: ' || "eventTypeText" || ' subtype: ' || "eventSubTypeText" || ' date: ' || "eventDate" || ' text: ' || "eventText",' | ') WITHIN GROUP( ORDER BY "eventTypeText") OVER(PARTITION BY bmb_id,"fullNameP","pepPrimaryName","eventDate") AS eventDetail,
"pepPrimaryName",
"entityMatchScore",
"supplierRiskScore",
"knownByName0",
listagg ("parameterDescription" || ': ' || "parameterValue",' | ') WITHIN GROUP( ORDER BY "parameterDescription") OVER(PARTITION BY bmb_id, "fullNameP","pepPrimaryName") AS other_parameters

FROM dt,
JSON_TABLE(pole_j, 
        '$' COLUMNS(
        NESTED PATH '$.principalsAndManagement.currentPrincipal[*]'
                COLUMNS("fullNameP" VARCHAR2(500) PATH '$.principalName.fullName' NULL ON ERROR,
                NESTED PATH '$.politicallyExposedPersons[*]'
                        COLUMNS("pepPrimaryName" VARCHAR2(500)  PATH '$.primaryName' NULL ON ERROR,
                                "entityMatchScore" VARCHAR2(500) path '$.entityMatchScore' NULL ON ERROR,
                                "supplierRiskScore" VARCHAR2( 500) path '$.supplierRiskScore' NULL ON ERROR,
                                "knownByName1" varchar2(500) path '$.personDetail.entityTypeText' ERROR ON ERROR,
                                "knownByName0" VARCHAR2(500) path '$.personDetail.name.primaryName' ERROR ON ERROR,
		 NESTED PATH '$.personDetail.eventDetail[*]' COLUMNS(
                                "eventTypeText" VARCHAR2(500) PATH '$.eventTypeText' NULL ON ERROR
                                ,"eventSubTypeText" VARCHAR2(500) PATH '$.eventSubTypeText' NULL ON ERROR
                                ,"eventDate"  VARCHAR2(500) PATH '$.eventDate' NULL ON ERROR
                                ,"eventText"  VARCHAR2(500)  PATH '$.eventText[0]' NULL ON ERROR
                            ) ,   
                        NESTED PATH '$.personDetail.nonspecificParameterDetail[*]' COLUMNS(
                                "parameterDescription"  VARCHAR2(500) PATH '$.parameterDescription' NULL ON ERROR
                                ,"parameterValue"  VARCHAR2(500)  PATH '$.parameterValue' NULL ON ERROR)                                            
                        ))))

AS jt;


fullNameP
eventTypeText
EVENTDETAIL
pepPrimaryName
entityMatchScore
supplierRiskScore
knownByName0
OTHER_PARAMETERS


xxx xxx
PEP
type: PEP subtype: ASC date: 2017-06-21 text: On List [PEP Connect - Poland]
Andrzej Jankowski
92
90
xxxxxx
: