oracle,把多列同时转成用逗号分割的一行，并去除重复数据

SELECT regexp_replace(create_user, '([^,]*)(,\1)+($|,)', '\1\3')    createUser,    regexp_replace(assign_user, '([^,]*)(,\1)+($|,)', '\1\3')    assignUser,    regexp_replace(user_name, '([^,]*)(,\1)+($|,)', '\1\3')    userName,    regexp_replace(firm_id, '([^,]*)(,\1)+($|,)', '\1\3') firmId,    regexp_replace(high_seas, '([^,]*)(,\1)+($|,)', '\1\3') highSeas    FROM    (SELECT listagg(create_user, ',') within GROUP(ORDER BY create_user)    create_user,    listagg(assign_user, ',') within GROUP(ORDER BY    assign_user) assign_user,    listagg(t1.user_name, ',') within GROUP(ORDER    BY t1.user_name)    user_name,    listagg(t1.firm_id, ',') within GROUP(ORDER    BY t1.firm_id) firm_id,    listagg(t1.high_seas, ',') within GROUP(ORDER    BY t1.high_seas) high_seas    FROM TABLE(XXXX_XXXX) t1)

orcale里的正则替换
regexp_replace(1,2,3,4,5,6)
语法说明：1：字段 2：替换的字段 3：替换成什么 4：起始位置（默认从1开始） 5：替换的次数（0是无限次） 6：不区分大小写