My script says Obj Vers Number is blank - but it can't be!

Question

hello.
And help.
I have below a script that includes several APIs to insert and update employees' details in ORACLE
Financials. It has been working fine until I've recently added the ' Hr_Person_Api.update_gb_person API'
After this, it throws up a ''ORACLE error occurred processing record.. ORA-20001: The mandatory
argument object_version_number value cannot be null..' message.
There is an entry in per_all_people_f the employee Im wanting to update which is collected by the CURSOR csr_ovn2. This is then opened (v_emp.std_employee_number) and FETCH'd INTO l_obj2 which is then put into the APIs. So why is it saying its blank?
Can someone please please read through the script and possibly offer a suggestion?
Many many thanks..
PLease find bellow relevant sections of my script..
   p_emp_number                     VARCHAR2 (30);
  l_obj2                            NUMBER;
-- Cursor retrieves latest Object Version Number from per_all_people_f table..
   CURSOR csr_ovn2 (p_person_emp_no IN per_all_people_f.employee_number%TYPE)
   IS
   SELECT MAX (per.object_version_number)
        FROM per_all_people_f per
     WHERE  per.employee_number = p_person_emp_no;
-- Process each record in the work table
   FOR v_emp IN get_employee_details
   LOOP
-- Obtain the most recent EMPLOYEE's Object Version Number..
      OPEN csr_ovn2 (v_emp.std_employee_number);
      FETCH csr_ovn2
       INTO l_obj2;
      IF csr_ovn2%NOTFOUND
      THEN
         RAISE NO_DATA_FOUND;
      END IF;
      CLOSE csr_ovn2;
            Hr_Person_Api.update_gb_person
                    (p_validate                 => l_validate,
                     p_effective_date                => SYSDATE,
                     p_datetrack_update_mode         => l_datetrack_update_mode,
                     p_person_id                     => emp_rec.person_id,
                     p_object_version_number         => l_obj2,
                     p_last_name                     => v_emp.std_last_name..

Answer 1

Try this
Change the cursor definition of csr_ovn2 to
CURSOR csr_ovn2 (p_person_id NUMBER,p_date DATE)
IS
SELECT per.object_version_number
FROM per_all_people_f per
WHERE per.person_id = p_person_id
AND p_date BETWEEN per.effective_start_date and per.effective_end_date
and call the cursor using
OPEN csr_ovn2(emp_rec.person_id,SYSDATE);