Oracle同一字段用逗号分隔(列转行)

--分组加排序，数据量大时结果会比较慢 

SELECT listagg(t.ename,‘,‘) WITHIN GROUP(ORDER BY t.sal) FROM scott.emp t;

查询结果为CLOB 

SELECT wm_concat(t.ename) FROM scott.emp t ORDER BY t.sal;