Null value in detail table's primary key

Question

I use Business Components Data Form to define a master-detail java panel.
I don't display the primary key column in the detail grid control.
Then I click on "+" to add a row, enter a value (the 2nd part of the detail table's primary key) and click commit.
I get an error saying that the primary key column that's not displayed is null and the row cann't be committed.
How do I fix this error?

Answer 1

My fields are varchar2's.
-- simplified to protect the guilty:
-- (made up from memory, so sql keywords may --be misspelled, but you get the idea)
create table proj (
proj varchar2(10) not null,
constraint proj_pk
primary key(proj)
insert into proj values ('abc');
commit;
-- this table has legal values for -- the master.legal field.
-- in master, legal was changed to a -- ComboBoxControl control from -- TextFieldControl that the wizard -- generated.
create table legal_values (
proj varchar2(10) not null,
legal varchar2(10) not null,
display_order integer not null,
constraint legal_values_pk
primary key (proj, legal)
insert into legal_values
values ('abc', 'one', 1);
insert into legal_values
values ('abc', 'two', 2);
insert into legal_values
values ('abc', 'three', 3);
commit;
create table master (
proj varchar2(10) not null,
masterKey varchar2(15) not null,
legal varchar2(10) not null,
constraint master_pk
primary key (proj, masterKey)
create table detail (
proj varchar(10) not null,
masterKey varchar(15) not null,
detailkey varchar(10) not null,
display_order integer not null,
status varchar2(12) not null, -- user can only update this field
constraint detail_pk
primary key(proj, masterkey, detailkey)
-- legal rows for detail table
create table detail_values (
proj varchar2(10) not null,
detailkey varchar2(10) not null,
display_order integer not null,
constraint detail_values_pk
primary key(proj, detailkey)
insert into detail_values values
('abc', 'status a', 1);
insert into detail_values values
('abc', 'status b', 2);
commit;
-- if their is a foriegn key on details back
-- to master, then you get the
-- "mutating table" error when trigger
-- occurs.
create or replace trigger master_tr
after insert on master
for each row
begin
insert into detail
(masterKey, detailKey, status, display_order, status)
select :new.masterkey, detail_key, display_order, ' '
from detail_values;
end;
-- detail.status is a comboboxControl getting --its values of of another db table too.
-- there's also "after update" triggers on master and detail tables that copy the record to master_history and "detail_history" tables if the corresponding table is modified. Thus we have a history of the changes made to the records. The 2 history tables have 2 additional fields than their parents, "modified_date date default sysdate not null" and "modified_by varchar2(30) default user not null" that record when and who made the change. There's also a change type field that records where the change is an insert, delete or update (there 3 triggers per table , so we can correctly record change type as being insert, delete or update into the change_type field).
If you want to make it more real to life, the status value is initially blank, then can be changed to a legal status value (complete or not complete), but can not be changed back to blank.
***P.S. I have to have this ready for production by monday.****
P.P.S After you reply and change to ComboBoxControls in 2 places, try changing the table names and/or the column names (say to follow the DBA's naming convention) or add another field to the composite primary key (and unstated foriegn key) (using drop table/create table). Now try getting the existing code to run. No writing down the old/new table (or column) name pair names. Just run the code and try to fix the code based on the error messages. Are the error messages giving you adequate information to find the problem?