Master Detail form in APEX 3.1

Question

Hi,
I am a bit new to the wonders of APEX (Only 1 project behind me).
On my current project I need to make a Master-Detail so I used the APEX template for that. However I have trouble setting my foreign key value in the detail table.
Table setup is like:
TABLE A(col_a pk, col_b)
TABLE B(col_a pk, col b)
TABLE C(col_aa, col_ba, col c)
I want to make a Master Detail between table A and table C. As I said I used the template and everything looks good - however no values are put into col_aa when I push the button to add a new row.
I want to initialize col_aa with the value from col_a when I add a new detail row - but I see no way to do this in a report column.
Can anyone provide me with some hints on how to do this ?
Kind regards
Bo Normann

Answer 1

First, how do you want this interaction to work? If you just put a button at the top of your detail section for creating new detail records, you could trigger this calculation via that button.
If I understand correctly, you don't really need values from the detail report. You need the primary key of the master record. If that's true, then you might try this.
1) Identify the name of the item on your master page that holds the primary key.
2) Identify the name of the item on your detail page that needs to get the value of the primary key from your master form.
3) Set the value of the detail item using a page branch that gets fired by your new record button.
Page branches provide declarative methods to set page items when the branch gets fired.
There are a lot of ways to do what you want. If either of these don't suite your needs you might want to be more specific about how you would like this operation to work.
Earl