oracle字符串分割

需求：现在需要判断TK_SURVEY 的字段scope(开放的部门)是否允许某个部门的人访问，需要判断
scope字段是否包含该部门，涉及到字符串的分割，可以采用自定义函数的方式来解决。
--CLOB 要分割的字符串
--p_sep分隔符，默认值,
CREATE OR REPLACE FUNCTION split (p_list CLOB, p_sep VARCHAR2 := ',')

    RETURN tabletype
    PIPELINED

IS
    l_idx    PLS_INTEGER;
    v_list   VARCHAR2 (32676) := p_list;
BEGIN
    LOOP
       l_idx   := INSTR (v_list, p_sep);

       IF l_idx > 0
       THEN
          PIPE ROW (SUBSTR (v_list, 1, l_idx - 1));
          v_list   := SUBSTR (v_list, l_idx + LENGTH (p_sep));
       ELSE
          PIPE ROW (v_list);
          EXIT;
       END IF;
    END LOOP;
END;

--分割字符后取出指定序号的字串
CREATE OR REPLACE FUNCTION splitstr (str IN CLOB,
                                        i   IN NUMBER := 0,
                                        sep IN VARCHAR2 := ','
)
    RETURN VARCHAR2

IS
    --t_i       NUMBER;
    t_count   NUMBER;
    t_str     VARCHAR2 (4000);
BEGIN
    IF i = 0
    THEN
       t_str   := str;
    ELSIF INSTR (str, sep) = 0
    THEN
       t_str   := sep;
    ELSE
       SELECT COUNT ( * )
       INTO t_count
       FROM table (split (str, sep));


       IF i <= t_count
       THEN
          SELECT str
          INTO t_str
          FROM (SELECT ROWNUM AS item, COLUMN_VALUE AS str
                FROM table (split (str, sep)))
          WHERE item = i;
       END IF;
    END IF;

    RETURN t_str;
END;


在sql中的运用：
select *
  from TK_SURVEY s
where exists
(select 1
          from (select COLUMN_VALUE scope from table(split('A', ','))) t
         where t.scope = s.scope)  and status = 'OPEN'