OK, that's clear for me now :)
It seems to work now :)
Thanks a lot Jason !

--- In IBObjects@yahoogroups.com, "Jason Wharton" <jwharton@i...> wrote:
>
> > With MyCursor do begin
> > Close ;
> > SQL.Text := 'SELECT ... WHERE ID = :ID' ;
> > ParamByName('ID').AsInt64 := id ; // id is a parameter of my
function
> > Prepare ;
> > First ;
> > Result := not (EOF and BOF) ;
> > end ;
>
> When you call ParamByName() the dataset is prepared automatically so
there
> is not actually a need to call Prepare explicitly and whenever you
alter the
> SQL property the dataset is closed and unprepared automatically.
>
> Having it in code though is good for clarity and readability for
others that
> may not be familiar with IBO but I just wanted you to know the internal
> behavior a little better. IBO lets your code be a bit sloppy I guess.
>
> This is how you should do it:
>
> With MyCursor do begin
> Close;
> Unprepare;
> SQL.Text := 'SELECT ... WHERE ID = :ID' ;
> Prepare;
> AutoFetchAll := false;
> ParamByName('ID').AsInt64 := id ; // id is a parameter of my function
> First ;
> Result := not EOF ;
> end ;
>
> Regards,
> Jason Wharton
>