> However, this approach doesn't work when I want to edit in a
> TIB_Grid, because AFAIK you can only display columns of the dataset,
> not some additional 'custom' columns.

There is a way to do this, but you need to be adventurous...

You create your own derivation of TIB_Query and override
GetColumnIsReadOnly
so that it will say that your calculated or computed fields are
editable.

You may need to setup your own CustomEdit and CustomInsert
processes that will take care of actually editing the desired column,
or you may be able to do it in other events - I dont have time to
experiment and see what would work in your situation.


--
Geoff Worboys - TeamIBO
Telesis Computing