Function in SQL: PRAGMA used, but '..does not guarantee not to update database'- WHY?

Question

I use function in SQL statement. It is a dynamicaly build SQL, therefore I need overload functions. These funcs defined in package. The package has PRAGMA Restrict_References (.., WNDS). So all functions should be restricted to update database.
But Oracle returns an error:
Function NVL_ does not guarantee not to update database
This is my build SQL:
----- the execution string is: ---------------
Begin
INSERT INTO TEST_TBL_BS (MILL_ORDER, CLM1, CLM2, CLM3, NOTES, INIT_DATE )
VALUES (NV.NVL_(Arc_Utl.TEST_TBL_dltd.MILL_ORDER),
NV.NVL_(Arc_Utl.TEST_TBL_dltd.CLM1),
NV.NVL_(Arc_Utl.TEST_TBL_dltd.CLM2),
NV.NVL_(Arc_Utl.TEST_TBL_dltd.CLM3),
NV.NVL_(Arc_Utl.TEST_TBL_dltd.NOTES),
Arch.Init_Time );
End;
This is NV package:
PACKAGE NV IS
PRAGMA Restrict_References ( NV, WNDS );
NULL_date DATE := TO_DATE ('01/01/1001', 'mm/dd/yyyy');
NULL_numb NUMBER := 0;
NULL_str VARCHAR2 (10)
:= '?';
-- overloaded NULL_Val function returns NULL_<type> value (defined early)
-- depend on received variable type
FUNCTION NULL_Val ( val_in IN DATE )
RETURN DATE ;
FUNCTION NULL_Val ( val_in IN NUMBER )
RETURN NUMBER ;
FUNCTION NULL_Val ( val_in IN VARCHAR2 )
RETURN VARCHAR2 ;
-- PRAGMA Restrict_References ( NULL_Val, WNDS ); -- can be used in SQLs
-- these pretends to cover hole of the SYS.NVL that do not have posibility
-- to return default NULL value for every given type
FUNCTION NVL_ ( val_in IN DATE )
RETURN DATE ;
FUNCTION NVL_ ( val_in IN NUMBER )
RETURN NUMBER ;
FUNCTION NVL_ ( val_in IN VARCHAR2 )
RETURN VARCHAR2 ;
-- PRAGMA Restrict_References ( NVL_, WNDS ); -- can be used in SQLs
END NV;
CREATE OR REPLACE PACKAGE BODY NV AS
-- NULL_Val set of overloaded functions - returns appropriate NULL value
FUNCTION NULL_Val ( val_in IN DATE )
RETURN DATE IS
BEGIN RETURN NULL_date;
END NULL_Val; -- for date
FUNCTION NULL_Val ( val_in IN NUMBER )
RETURN NUMBER IS
BEGIN RETURN NULL_numb;
END NULL_Val; -- for NUMBER
FUNCTION NULL_Val ( val_in IN VARCHAR2 )
RETURN VARCHAR2 IS
BEGIN RETURN NULL_str;
END NULL_Val; -- for VARCHAR2
-- set NVL_ function to return default NULL value if received variable
-- is NULL or the received variable if it is not NULL
FUNCTION NVL_ ( val_in IN DATE )
RETURN DATE IS
BEGIN RETURN NVL( val_in, NULL_Val ( val_in )); END NVL_;
FUNCTION NVL_ ( val_in IN NUMBER )
RETURN NUMBER IS
BEGIN RETURN NVL( val_in, NULL_Val ( val_in )); END NVL_;
FUNCTION NVL_ ( val_in IN VARCHAR2 )
RETURN VARCHAR2 IS
BEGIN RETURN NVL( val_in, NULL_Val ( val_in )); END NVL_;
END NV;
Can anybody help : where is a problem and what I can do in my case?
I work in Oracle 7.3
Thank you,
Alex

Answer 1

Hi Alex,
I've found that on the RDBS docs:
If you specify DEFAULT instead of a function name, the pragma applies to all functions in the package spec or object type spec (including, in the latter case, the
system-defined constructor). You can still declare the pragma for individual functions. Such pragmas override the default pragma.
Try using that and let me know.
The docs says also that the declaration of the pragma for an overloaded function applies to the nearest one. You may also try to insert several declaration, one after every function declaration.
Bye Max