oracle 查询分隔符分隔开的所有数据

SELECT REGEXP_SUBSTR('first field, second field , third field', '[^,]+', 1, level) AS split_data
FROM dual
CONNECT BY REGEXP_SUBSTR('first field, second field , third field', '[^,]+', 1, level) IS NOT NULL
AND PRIOR dbms_random.value IS NOT NULL
AND PRIOR 'first field, second field , third field' = 'first field, second field , third field';