-- https://docs.oracle.com/en/database/oracle/oracle-database/23/sqlrf/JSON_DATAGUIDE.html
SELECT EXTRACT(YEAR FROM date_loaded) YEAR,
       JSON_DATAGUIDE(po_document) "DATA GUIDE"
  FROM j_purchaseorder
  GROUP BY extract(YEAR FROM date_loaded)
  ORDER BY extract(YEAR FROM date_loaded) DESC;