一条经典的处理语句

  T := '205, 207, 197,';
  IF (T IS NOT NULL) AND (LENGTH(T) > 0) THEN
    WHILE LENGTH(T) > 0 LOOP
      S := TRIM(SUBSTR(T, 1, INSTR(T, ',') - 1));
      IF LENGTH(S) > 0 THEN
        DBMS_OUTPUT.PUT_LINE('S:' || S);
      END IF;
      T := SUBSTR(T, INSTR(T, ',') + 1);
    END LOOP;
  END IF;