SQL Befehl (SELECT Begriff FROM Tabelle) Was stimmt nicht?

[Plague]

Der Code ist dieser:

Delphi-Quellcode:

procedure TForm1.Button2Click(Sender: TObject);
var
LI: TListItem;
q :string;
begin
q:= Combobox1.Text;
with ZReadOnlyQuery1 do
  begin
    close;
    SQL.Clear;
    SQL.Text := ('SELECT * FROM Tabelle WHERE '+q);
    open;
    ListView1.Items.BeginUpdate; 
    Listview1.Items.Clear; 
    while not (EOF) do
    begin 
      LI := Listview1.Items.Add;
      LI.ImageIndex := 0;
      LI.Caption := (FieldByName('ID').AsString);
      LI.SubItems.Add(FieldByName('Spalte1').AsString);
      LI.SubItems.Add(FieldByName('Spalte2').AsString);
      LI.SubItems.Add(FieldByName('Spalte3').AsString);
      LI.SubItems.Add(FieldByName('Spalte4').AsString);
      LI.SubItems.Add(FieldByName('Spalte5').AsString);
      LI.SubItems.Add(FieldByName('Spalte6').AsString);
      LI.SubItems.Add(FieldByName('Spalte7').AsString);
      LI.SubItems.Add(FieldByName('Spalte8').AsString);
      Next; 
    end; 
    ListView1.Items.EndUpdate; 
    close; 
  end;
end;