oracle中过滤中文字符或者汉字的函数

CREATE OR REPLACE FUNCTION GET_CHINESE(P_NAME IN VARCHAR2) RETURN VARCHAR2 IS
 V_CODE        VARCHAR2(30000) := '';
 V_CHINESE     VARCHAR2(4000) := '';
 V_NON_CHINESE VARCHAR2(4000) := '';
 V_COMMA       PLS_INTEGER;
 V_CODE_Q      PLS_INTEGER;
 V_CODE_W      PLS_INTEGER;
BEGIN
 IF P_NAME IS NOT NULL THEN
  SELECT REPLACE(SUBSTRB(DUMP(P_NAME, 1010), INSTRB(DUMP(P_NAME, 1010), 'ZHS16GBK:')), 'ZHS16GBK: ', '') INTO V_CODE FROM DUAL WHERE ROWNUM = 1;
  FOR I IN 1 .. LENGTH(P_NAME) LOOP
   IF LENGTHB(SUBSTR(P_NAME, I, 1)) = 2 THEN
    V_COMMA  := INSTRB(V_CODE, ',');
    V_CODE_Q := TO_NUMBER(SUBSTRB(V_CODE, 1, V_COMMA - 1));
    V_CODE_W := TO_NUMBER(SUBSTRB(V_CODE, V_COMMA + 1, ABS(INSTRB(V_CODE, ',', 1, 2) - V_COMMA - 1)));
    IF V_CODE_Q >= 176 AND V_CODE_Q <= 247 AND V_CODE_W >= 161 AND V_CODE_W <= 254 THEN
     V_CHINESE := V_CHINESE || SUBSTR(P_NAME, I, 1);
    ELSE
     V_NON_CHINESE := V_NON_CHINESE || SUBSTR(P_NAME, I, 1);
    END IF;
    V_CODE := LTRIM(V_CODE, '1234567890');
    V_CODE := LTRIM(V_CODE, ',');
   END IF;
   V_CODE := LTRIM(V_CODE, '1234567890');
   V_CODE := LTRIM(V_CODE, ',');
  END LOOP;
  /*IF P_CHINESE = '1' THEN
            RETURN V_CHINESE;
        ELSE
            RETURN V_NON_CHINESE;
        END IF;*/
  IF LENGTH(V_CHINESE) > 0 THEN
   RETURN V_CHINESE;
  ELSIF LENGTH(V_NON_CHINESE) > 0 THEN
   RETURN V_NON_CHINESE;
  ELSE
   RETURN '';
  END IF;
 ELSE
  RETURN '';
 END IF;
END GET_CHINESE;

使用方法：SELECT /*+ parallel(a,10)*/ A.*, ROWID FROM   ABC_TABLE A where length(GET_CHINESE(logic_phone))>0