I think I have discovered a bug in the handling of null values (vs NULL
values) passed as parameters to a stored proc.

I have always believed that the database handled NULL and null the
same. The following statement returns the expected results:

select case when NULL is null then 'SAME' else 'DIFFERENT' end from
sysibm.sysdummy1;

returns SAME.

BUT, If you call a proc with lower case null as a parameter, it will
not be treated as a NULL.

Here's an example proc:

CREATE PROCEDURE RG.NULLTEST(IN PARM1 VARCHAR(26))
SPECIFIC NULLTEST
MODIFIES SQL DATA
NOT DETERMINISTIC
NULL CALL
LANGUAGE SQL

P1: BEGIN

DECLARE c1 CURSOR WITH RETURN TO CALLER FOR
SELECT 'PARM1 IS NULL' AS R1 FROM SYSIBM.SYSDUMMY1;

DECLARE c2 CURSOR WITH RETURN TO CALLER FOR
SELECT 'PARM1 IS NOT NULL' AS R1 FROM SYSIBM.SYSDUMMY1;

if PARM1 IS null THEN

OPEN c1;

ELSE

OPEN c2;

END IF;

END P1
;


CALL RG.NULLTEST(null);

returns PARM1 IS NOT NULL

BUT

CALL RG.NULLTEST(NULL);

PARM1 IS NULL

It's easy enough to code around, but frustrating when the database
violates a basic assumption.

Has anyone else encountered this issue?

Bob