public function orderBy($key, $mode = 'ASC', $options = SORT_REGULAR)
    {
        return $this->sortBy($key, $options, ($mode === 'DESC' ? true : false));
    }
public function orderBy($key, $mode = 'ASC', $options = SORT_REGULAR)
    {
        return $this->sortBy($key, $options, ($mode === 'DESC' ? true : false));
    }
public function orderBy ( $ key , $ mode = 'ASC' , $ options = SORT_REGULAR ) { return $ this -> sortBy ( $ key , $ options , ( $ mode === 'DESC' ? true : false ) ) ; }
Perform order by.
It performs similar to sortBy method of collection but simplifies parameter order.

@param  $key
@param  string $mode
@param  int    $options
@return PostCollection
Perform order by . It performs similar to sortBy method of collection but simplifies parameter order .