public function addGroupBy($columns) { if (!is_array($columns)) { $columns = [$columns]; } $newColumns = []; foreach ($columns as $column) { if ($column == 'pk') { $column = $this->model->getPkName(); } $newColumns[] = $this->quoteColumnName($this->tableAlias . '.' . $column); } return parent::addGroupBy($newColumns); }