Yajra\Datatables\Request::columnName PHP Method

    public function columnName($i)
    {
        $column = $this->input("columns.{$i}");
        return isset($column['name']) && $column['name'] != '' ? $column['name'] : $column['data'];
    }

 /**
  * Get column name to be use for filtering and sorting.
  *
  * @param integer $index
  * @param bool $wantsAlias
  * @return string
  */
 protected function getColumnName($index, $wantsAlias = false)
 {
     $column = $this->request->columnName($index);
     // DataTables is using make(false)
     if (is_numeric($column)) {
         $column = $this->getColumnNameByIndex($index);
     }
     if (Str::contains(Str::upper($column), ' AS ')) {
         $column = $this->extractColumnName($column, $wantsAlias);
     }
     return $column;
 }