By default, VFP does NOT read ALL the data into memory.

You're doing something other than "just opening" if it is.

The mechanics are simple: VFP "adds" to the "end of a table"; it only needs to read the Header to figure out where the end is ... it doesn't have to read "everything in between".

I can open a DBF (no order set, no prior opens), append a record, and close a DBF (multiple indexes) with 360,000 records (144 MB) in less than a second ...

If you're so concerned about "network traffic", you should create a remote VFP COM server and pass your "single insert" to that.

>> Why?, opening the table should not be a problem
>
>Ooooh!
>It's a big problem in VFP. When I opening a table VFP reads all data from the table to memory for some reasons. If I have a 100,000 records (small number for normal DB) it's becomes a problem in VFP.
>
>
>> how can you write to a file without opening it?
>
>I did not tell "without opening". I told "without reading data back".