Tutorials - Navigation, Triggers

Question

- I refer to the advanced tutorial - How to create a Tabular Form:
http://download.oracle.com/docs/cd/E14373_01/appdev.32/e13363/frm_tabular.htm#CHDFBHDB
I have two problems there:
1. After Application is created I do not have Navigation Link from Page1 to Tabular Form itself
How do I add it there?
2. I can not add new employee using Tabular Form. When I press Add Row, it adds a row with null value for Employee ID and then, when I click Submit I get an error that I can't add Null value into EMPLOYEE_ID:
Error in mru internal routine: ORA-20001: Error in MRU: row= 1, ORA-01400: cannot insert NULL into ("CSDB"."OEHR_EMPLOYEES"."EMPLOYEE_ID"), insert into "CSDB"."OEHR_EMPLOYEES" ( "EMPLOYEE_ID", "FIRST_NAME", "LAST_NAME", "HIRE_DATE", "SALARY", "DEPARTMENT_ID") values ( :b1, :b2, :b3, :b4, :b5, :b6)
Am I missing something there
Is there a solution?
- Same with Tutorial of AnyCo Corp: http://download.oracle.com/docs/cd/E14373_01/appdev.32/e13367/build_app.htm#BCEIBDHI
I get the same Error, when trying to Create new Employee entry:
ORA-01400: cannot insert NULL into ("CSDB"."OEHR_EMPLOYEES"."EMPLOYEE_ID")
It seems that I'm missing a trigger or a sequence...
How do I fix it, please...??
Thank you...

Answer 1

Hi Sloger,
I had the same problem with Tutorial of AnyCo Corp and I fixed it by implementing a new "Page Process" in "Processes"-area of page definition:
1. Choose "Create" in area "Processes"
2. As process category take "PL/SQL", then click "Next"
3. As name take something like "Get_PK" and sequence should be a small integer, so that this process is executed first before all other (check "Existing Processes" and if the lowest integer is 10, so take 5 for example). Go on with "Next"
4. As "PL/SQL Page Process" take the following code:
declare
function get_pk return varchar2
is
begin
DECLARE
L_PRIMARY_KEY NUMBER;
BEGIN
SELECT MAX(EMPLOYEE_ID) + 1
INTO L_PRIMARY_KEY
FROM OEHR_EMPLOYEES;
RETURN L_PRIMARY_KEY;
END;
end;
begin
:P4_EMPLOYEE_ID := get_pk;
end;
5. Then click on "Create Process"
6. Now, you should find a Process "Get_PK" in "Processes". Click on the name to edit the properties.
7. Scroll down to "When Button Pressed (Process After Submit When this Button is Pressed)" and select "CREATE (Create)".
8. Apply the changes.
Now, you should be able to enter new employees to table OEHR_EMPLOYEES with EMPLOYEE_ID filled by value.
Hope, this works for you as well as it did for me?!
Regards
FF