ado filter

I opened a recordset using the flag adLockBatchOptimistic. This way I can
make changes to the recordset and when needed, the changes are transferred
to the database using the "Update" method.
The problem is that when I use the Filter on such a recordset, it doesn't
see the changes I made until I use the Update method. How can I make the
Filter look through both the records that are already in the database and
the ones that are still in the recordset buffer?

What's the cursor type? If you didn't set it, you use a forward only cursor (the default) and it's a static copy of your records. Maybe you should use the adOpenKeyset or the adOpenDynamic cursor

ex. :

Set rs = CreateObject("ADODB.Recordset")
rs.CursorType = adOpenKeyset
rs.LockType= adLockBatchOptimistic
...
rs.Open ...

BTW, you should use UpdateBatch method instead of Update method

Marc