将excel表数据加载到codeigniter中的db中

Question

iam need to load excelsheet data into database using codeigiter.for that i have tried this coding

function excel_data()
    {
//include 'PHPExcel/IOFactory.php';
  $this->load->library("PHPExcel");
 $inputFileName = '../first_data.xls';


//  Read your Excel workbook
try {
    $inputFileType = PHPExcel_IOFactory::identify($inputFileName);
    $objReader = PHPExcel_IOFactory::createReader($inputFileType);
    $objPHPExcel = $objReader->load($inputFileName);
} catch(Exception $e) {
    die('Error loading file "'.pathinfo($inputFileName,PATHINFO_BASENAME).'": '.$e->getMessage());
}

//  Get worksheet dimensions
$sheet = $objPHPExcel->getSheet(0); 
$highestRow = $sheet->getHighestRow(); 
$highestColumn = $sheet->getHighestColumn();

//  Loop through each row of the worksheet in turn
for ($row = 1; $row <= $highestRow; $row++){ 
    //  Read a row of data into an array
    $rowData = $sheet->rangeToArray('A' . $row . ':' . $highestColumn . $row,
                                    NULL,
                                    TRUE,
                                    FALSE);
    //  Insert row data array into your database of choice here
    // $this->User_model->add_data($rowData);
}

 }

while executing iam getting this error "Error loading file "first_data.xls": Could not open ../first_data.xls for reading! File does not exist." what is the problem in my coding.

what is my mistake.did anyone knows that?