On tab pages, where tabs are children of home page ... how2insert rows?

Question

We show the key on the parent tab ... we navigate to child tabs, and proper child rows are all there.
We click insert and it seems to allow entry. We click Submit, we get error that the parent key field is blank, so can't do insert.
So ... how to make that parent key persist on each child tab?
The tabs know the key is there, because they successfully show the children, and only the children. And when you click on a different parent on the row listing of the main home page, then go to child, only that new row's children show up (my intern did the links, I can't speak for precisely how he did this, but we're talking meat and potatoes, not wizardry).
Any records entered on a child tab should be a child of the clicked home parent, and no other record (one must start with parent before going to child) ...
Is there a way to get the parent key to persist?
(child tabs typically have two columns making up the primary key, the parent key (as a foreign key) and something unique to that tab ... e.g., line number, or xref code, or id_link ... these tables / keys all work just fine at the SQLplus level and via Oracle Forms, so data model per se is fine.)
Any / all clues / info / links to docs will be met with much gratitude.
Suzanne

Answer 1

Suzanne:
It would make it easier for your problem to be understood/resolved if you could create a example of the issue you are encountering at the OTN APEX site.
Given the information you have provided, and assuming that the 'DML' for child records is handled by the standard APEX Automatic DML processing page process, I'd suggest you take a look at the definition of this process and determine how the PK for the child record is obtained.
Varad