-- JSON Function: JSON_OBJECTAGG

SELECT
  JSON_OBJECTAGG(
          KEY  ref_desc
          VALUE  ref_id)  JSON_OBJECTAGG_
FROM
 (SELECT
    level*10  ref_id,
    TO_CHAR(TO_DATE(level*10,'J'),'JSP') ref_desc  
  FROM  DUAL
  CONNECT BY level < 5)
;