w/IBO 4.2Hd, D7, and Fb 1.54

I'm working with a VirtualTreeview and two Tables:

One Table contains data on the folder nodes for the
VirtualTreeview, including whether the folder has
any documents that it owns.

The other Table contains rows for documents - notes -
including a blob.

The VirtualTreeview must know the exact count of
child nodes it will have, when the parent node is created.

This is currently maintained by a select statement on
the notes table with the simple criteria for the folder parent node,
and then using the IBOQuery.RecordCount value passed to the
VirtualTreeview InitChildren event.

I suspect that having to obtain these RecordCount results
for each level 0 node is a very, very costly process:
my folder table currently had 172 folder rows.

I'm wondering if there is a more efficient approach.

One that has occurred to me is to maintain a count
of the child node requirements, i.e., maintain a count of
the number of document records to be called for each folder
in a field of the folder, increasing and decreasing that
value as required.

I'd appreciate any opinions on this type of requirement.