public function group($columns)
    {
        settype($columns, 'array'); //force to an array

        $this->group = array_unique(array_merge($this->group, $columns));
        return $this;
    }
public function group($columns)
    {
        settype($columns, 'array'); //force to an array

        $this->group = array_unique(array_merge($this->group, $columns));
        return $this;
    }
public function group ( $ columns ) { settype ( $ columns , 'array' ) ; //force to an array $ this -> group = array_unique ( array_merge ( $ this -> group , $ columns ) ) ; return $ this ; }
Built the group clause of the query

@param   array|string    A string or array of ordering columns
@return  AnDatabaseQuery
Built the group clause of the query