ORA-03115: unsupported network datatype or representation

测试实例如下：

SQL> CREATE OR REPLACE FUNCTION factorial
2 ( n BINARY_DOUBLE ) RETURN BINARY_DOUBLE IS
3 BEGIN
4 IF n <= 1 THEN
5 RETURN 1;
6 ELSE
7 RETURN n * factorial(n - 1);
8 END IF;
9 END factorial;
10 /

函数已创建。

SQL> select factorial(4) from dual;
select factorial(4) from dual
*
ERROR 位于第 1 行:
ORA-03115: unsupported network datatype or representation

修改函数数据类型：

SQL> CREATE OR REPLACE FUNCTION factorial
2 ( n number ) RETURN number IS
3 BEGIN
4 IF n <= 1 THEN
5 RETURN 1;
6 ELSE
7 RETURN n * factorial(n - 1);
8 END IF;
9 END factorial;
10 /

函数已创建。

SQL> select factorial(4.0) from dual;

FACTORIAL(4.0)
--------------
24

SQL> select factorial(4) from dual;

FACTORIAL(4)
------------
24

居然没有报错了，跟数据类型有关？