convention for main update button when subforms are used

[jonefer]

I'm implementing a hybrid - bound-form, but not bound-control format. I
create a core record and then restrain updates directly in the textboxes
until the user clicks an 'update' button.

I'm just curious, short of creating temp tables for all my children records
(there are 2 subforms with children records), what is the convention of
restraining the updates in the subforms until a button on the 'main' form is
clicked? And since this is in an ADP connected to SQL Server, I would
refrain from creating temp records.