oracle 中可以用connect by把字符串按逗号分割

比如定义字符串：
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
返回结果：
TOKEN
23
34
45
56