菜鸟向各位高手们求一段sql代码

[charmy00]

我有一个表字段存储的数据类似这样：
fashion scarf
mens plaid scarf
cashmere scarf for men
mens grey scarves
mens grey scarf

我需要取出这个字段值的集合（无重复的单词），返回一个字符串，结果是：

mens fashion plaid grey scarves cashmere scarf for men（单词顺序无所谓）

请问sql语句要怎么写呀？

谢谢大家！！！

[chengccy]

先拆, 再去重, 再合并字符串

WITH TMP AS
 (SELECT 'fashion scarf' S
  FROM   DUAL
  UNION ALL
  SELECT 'mens plaid scarf' S
  FROM   DUAL
  UNION ALL
  SELECT 'cashmere scarf for men' S
  FROM   DUAL
  UNION ALL
  SELECT 'mens grey scarves' S
  FROM   DUAL
  UNION ALL
  SELECT 'mens grey scarf' S
  FROM   DUAL)
SELECT LISTAGG(S, ' ') WITHIN GROUP(ORDER BY S)
FROM   (SELECT DISTINCT REGEXP_SUBSTR(S, '[^ ]+', 1, LEVEL) AS S
         FROM   TMP
         CONNECT BY LEVEL <= REGEXP_COUNT(S, '[ ]+') + 1
             AND    PRIOR S = S
             AND    PRIOR DBMS_RANDOM.VALUE IS NOT NULL)