oracle如何拆分以逗號分隔的字符串為多列？

oracle 中可以用connect by把字符串按都好分割：

比如定義字符串：

pv_no_list :='23,34,45,56';

SELECT DISTINCT REGEXP_SUBSTR (pv_no_list,'[^,]+',1,LEVEL) as "token"

FROM DUAL

CONNECT BY REGEXP_SUBSTR (pv_no_list,'[^,]+',1,LEVEL) IS NOT NULL

order by 1

返回結果：

TOKEN

23

34

45

56