Thanks Thomas. That fixes the display problem. I also set up a
parameter in the OnPrepareSQL
(SQLWhereItems.Add('ID = :P_ID');).

I wrote the code as
if active then begin
InvalidateSQL;
ParamByName('P_ID').AsInteger := CustId;
Refresh;
else...//query not open

I occasionally get an AV when it executes the ParamByName statement.
The AV appears to occur in the IBA_Column.IMP unit in the
TIB_ColumnInteger.SetValue function. I can probably live with it with
a silent exception, but do you think my code is correct? Thanks.

--- In IBObjects@y..., "Thomas Steinmaurer" <ts@i...> wrote:
> If your query is already open, then you can execute:
>
> qry.InvalidateSQL;
> qry.Refresh;
>
> This will fire the OnPrepareSQL event and refreshes your
> dataset with the newly set WHERE clause
>
> Best Regards
> Thomas Steinmaurer
> IB LogManager 2.0 - The Logging Tool for Interbase/Firebird
> http://www.iblogmanager.com
>