[marcoszorrilla]

Prueba con esto:

Código Delphi [-]
procedure TForm1.Button1Click(Sender: TObject);
Var
n:Integer;
begin

  for n:=0 to Query1.FieldCount -1 do
  begin
    if Query1.fields[n].DataType = ftFloat then
      TFloatField(Query1.Fields[n]).DisplayFormat := ',0.00';
  end;
end;

Un Saludo.