TÉMA:

  if ( SQLQuery.FieldByName('limit').AsFloat < SQLQuery.FieldByName('qty').AsFloat ) then begin
    with (Sender As TDBGrid) do
    begin
      //Custom drawing
      Canvas.Brush.Color:=clRed;
      Canvas.Font.Color:=clBlack;
      Canvas.Font.Style:=[fsBold];
    end;
  end;

procedure TForm1.DBGrid1PrepareCanvas(sender: TObject; DataCol: Integer; Column: TColumn; AState: TGridDrawState);
begin
	if (TDBGrid(Sender).DataSource.DataSet.FieldByName('mező_neve').AsString = 'érték') then begin
		TDBGrid(Sender).Canvas.Brush.Color:=clRed;
		TDBGrid(Sender).Canvas.Font.Color:=clBlack;
		TDBGrid(Sender).Canvas.Font.Style:=[fsBold];
	end;
end;

procedure TForm1.DBGrid1PrepareCanvas(sender: TObject;
  DataCol: Integer; Column: TColumn; AState: TGridDrawState);
begin
  if ( Column.FieldName='name' ) and (  Column.Field.AsString='akarmi' ) then begin
    with (Sender As TDBGrid) do
    begin
      //Custom drawing
      Canvas.Brush.Color:=clRed;
      Canvas.Font.Color:=clBlack;
      Canvas.Font.Style:=[fsBold];
    end;
  end;
end;