/**
* Add a group by expression to the query.
*
* @param string $column
* @param string|null $orderMode
*
* @return $this The same instance to concatenate methods
*/
public function groupBy($column, $orderMode = null)
{
$columnObj = $this->factory->references('Column', $column);
$orderModeObj = $orderMode ? $this->factory->references('OrderModeEnum', $orderMode) : null;
$this->select->groupBy($columnObj, $orderModeObj);
return $this;
}
