关于clob类型在函数中的处理。

create or replace type str2tblType as table of varchar2(4000);

CREATE OR REPLACE FUNCTION str2tbl (p_str     IN CLOB,
                                    p_delim   IN VARCHAR2 DEFAULT ',')
   RETURN str2tbltype
AS
   l_str    CLOB := p_str || p_delim;
   l_n      NUMBER;
   l_data   str2tbltype := str2tbltype ();
BEGIN
   LOOP
      l_n := INSTR (l_str, p_delim);
      EXIT WHEN (NVL (l_n, 0) = 0);
      l_data.EXTEND;
      l_data (l_data.COUNT) := LTRIM (RTRIM (SUBSTR (l_str, 1, l_n - 1)));
      l_str := SUBSTR (l_str, l_n + 1);
   END LOOP;

   RETURN l_data;
END;
/

-------------------------------------实现--------------------------------------

DECLARE
  v CLOB;
  r str2tblType;
BEGIN
  v := LPAD('A',4000)||','||LPAD('B',4000);
  r := str2tbl(v);
  FOR i IN 1..r.COUNT LOOP
      DBMS_OUTPUT.PUT_LINE(r(i));
  END LOOP;
END;
/

or

select * from table(cast(str2tbl(LPAD(to_clob('A'),4000)||','||LPAD(to_clob('B'),4000)) as str2tblType));

以下写法是错误的如果传入长度大于4000，传入的非Clob 类型.

select * from table(cast(str2tbl(LPAD('A',4000)||','||LPAD('B',4000)) as str2tblType));