public function addColumn($column, $aggregationFunction = false)
    {
        if (is_array($column)) {
            foreach ($column as $c) {
                $this->addColumn($c, $aggregationFunction);
            }
            return;
        }
        $this->additionalColumns[$column] = $aggregationFunction;
    }
public function addColumn($column, $aggregationFunction = false)
    {
        if (is_array($column)) {
            foreach ($column as $c) {
                $this->addColumn($c, $aggregationFunction);
            }
            return;
        }
        $this->additionalColumns[$column] = $aggregationFunction;
    }
public function addColumn ( $ column , $ aggregationFunction = false ) { if ( is_array ( $ column ) ) { foreach ( $ column as $ c ) { $ this -> addColumn ( $ c , $ aggregationFunction ) ; } return ; } $ this -> additionalColumns [ $ column ] = $ aggregationFunction ; }
Add a column that has be added to the outer queries.

@param $column
@param string|bool $aggregationFunction If set, this function is used to aggregate the values of "Others",
eg, `'min'`, `'max'` or `'sum'`.
Add a column that has be added to the outer queries .