update from data*** view

Hi,
I have a subform in the Data*** view, not all the fields are
displayed. When a new record is entered, the hidden fields are not updated.
e.g. I know the primary key of the record and it's not displayed on the
subform. How can I manually pass that in when the record is updated.

let say the record has the following fields
order# (hidden), Qty (shown), item# (shown).
when the user can only enter Qty and Item#, how do I append Order# to the
record?


Thanks.


.

Loading