codeigniter with oracle database

[eluser]selvercode[/eluser]
hello every body
i create function from oracle database "PL/SQL" and i want to call this function from codeigniter i am tried to use :
$this->db->call_function('ORCL.ADD_NEW(45 , "first", "second")');

but display "This feature is not available for the database you are using."
can any one help me ,if exist any ways...?

[eluser]InsiteFX[/eluser]
Use the db->query method, the one you are trying to use is Active Record for MySQL etc;

[eluser]selvercode[/eluser]
see this function :
FUNCTION ADD_PRODUCT($new_product_array1) {
$values = array(487, 'product_name', random_string());
$query['dsa']= $this->db->query("CALL PRODUCT_ACTIONS.INSERT_PRODUCT(?, ?,?)", $values);

echo "ok";
}

--------------
this PL/SQL function
FUNCTION ADD_PRODUCT
(
PRODUCT_ID IN NUMBER ,
PRODUCT_NAME IN VARCHAR2 ,
PRODUCT_NUMBER IN VARCHAR2,
resultt OUT VARCHAR2
) RETURN VARCHAR2 AS
BEGIN
resultt := 'true';
Insert into PRODUCTS (PRODUCT_NAME,PRODUCT_NUMBER,PRODUCT_TYPE,QUANTITY,MEASURMENT_UNIT,PRODUCT_SIZE,ADDED_DATE,MODIFIED_DATE,NOTES) values (PRODUCT_NAME,PRODUCT_NUMBER,'sdsa',1112,'aasd','asd',null,null,'asdasd');
RETURN resultt;
END ADD_PRODUCT;
-------------------------------
the result it insert into database but display error and not return value???

[eluser]InsiteFX[/eluser]
Try converting the number 487 to a string.

Code:

$values = array('487', 'product_name', random_string());

[eluser]selvercode[/eluser]
Message: Object of class CI_DB_oci8_result could not be converted to string
this display when i do echo $query
how i can echo reurned value ?
----------------
and why this message display
Message: oci_fetch_assoc(): ORA-24374: define not done before fetch or execute and fetch


thanks for your replay