sql来，请教怎么将查询的一列数据拼接用逗号隔开显示成一条记录

WITH t AS(SELECT 1322049461 a FROM dualUNION ALLSELECT  1322041123    FROM dualUNION ALLSELECT  1322049461 FROM dual)--9iSELECT max(substr(sys_connect_by_path(a,','),2)) bFROM        (SELECT a,row_number() over(ORDER by a) rn FROM t) START WITH rn=1 CONNECT BY rn-1=PRIOR rn--10gselect wm_concat(a,',') from t