PHPExcel library hangs with relative "big" files - php

Question

I'm trying to export some records to excel from my MySQL (webserver) and when the query returns >4k records the script hangs the web browser and temporaly the web hosting.
My PHP_version is 5.2.13-pl1-gentoo and the memory_limit configurated in php.ini is 128M
The result excel only have one column and N rows. With 100 or 200 rows the php script runs fine.
This is the php script
<? session_start();
ini_set('memory_limit', '1024M');
set_time_limit(0);
include("include/conexion.php");
require_once 'include/PHPExcel/Classes/PHPExcel.php';
require_once 'include/PHPExcel/Classes/PHPExcel/IOFactory.php';
$objPHPExcel = new PHPExcel();
$objPHPExcel->getProperties()->setCreator("Name")
->setLastModifiedBy("Name")
->setTitle("Listado")
->setSubject("Listado")
->setDescription("Listado.")
->setKeywords("Listado")
->setCategory("Listado");
$query = explode("|",stripcslashes($_POST['query']));
$objPHPExcel->getActiveSheet()->setTitle('List');
$resEmp = mysql_query ($query, $conexion ) or die(mysql_error());
$tot = mysql_num_rows($resEmp);
$num_fields = mysql_num_fields($resEmp);
$fistIndex = $objPHPExcel->getActiveSheet()->getCellByColumnAndRow(0, 1)->getColumn();
$lastIndex = $objPHPExcel->getActiveSheet()->getCellByColumnAndRow($num_campos - 1, 1)->getColumn();
//tittles
for ($e=0;$e < $num_fields;$e++){
$objPHPExcel->getActiveSheet()->setCellValueByColumnAndRow($e, 2, utf8_decode(ucwords(mysql_field_name($resEmp,$e))));
$objPHPExcel->getActiveSheet()->getColumnDimension($objPHPExcel->getActiveSheet()->getCellByColumnAndRow($e, 2)->getColumn())->setAutoSize(true);
}
//color tittles
$objPHPExcel->getActiveSheet()->getStyle( $fistIndex.'1:'.$lastIndex.'2' )->getFill()->setFillType(PHPExcel_Style_Fill::FILL_SOLID)->getStartColor()->setRGB('c5c5c7');
$objPHPExcel->getActiveSheet()->getStyle( $fistIndex.'1:'.$lastIndex.'2' )->getFont()->setBold(true);
if(isset ( $_POST ['mail'] )){
$objPHPExcel->getActiveSheet()->setCellValueByColumnAndRow(0, 2, "Email");
$emails = array();
for ($row = 0; $row < $totEmp; $row++) {
//more than one mail in field separated by ";"
$aux = explode(";", mysql_result($resEmp,$row,$col));
for($i=0; $i<count($aux); $i++){
$cleaned = utf8_encode(strtolower(trim($aux[$i])));
//filter repeated mails
if(!in_array($cleaned, $emails) && $aux[$i] != ""){
$num_rows = $objPHPExcel->getActiveSheet()->getHighestRow();
$objPHPExcel->getActiveSheet()->insertNewRowBefore($num_rows + 1, 1);
array_push($emails, $cleaned);
$objPHPExcel->getActiveSheet()->setCellValueByColumnAndRow(0, $num_rows + 1, $cleaned);
}
}
}
}
$objWriter = PHPExcel_IOFactory::createWriter($objPHPExcel, 'Excel2007');
header('Content-type: application/vnd.ms-excel');
header("Content-Disposition: attachment; filename=".$nom_archivo.".xlsx");
// Write file to the browser
$objWriter->save('php://output');
exit();
?>
When enter to the script run a mysql query and then, iterate the result to get the mail field, if the obtained mail not exist in a array this mail is inserted in excel
I've tried to set
ini_set('memory_limit', '1024M');
set_time_limit(0);
But the problem persist.
Any idea to solve problem?
Thanks a lot
EDIT 1
I've updated the code with the recommendations and now works fine.
Anyway How can I get if occurs any error or the memory usage just before of hanging?
How can I get the max memory_limit available to set with ini_set('memory_limit', '2048M'); ?
<? session_start();
ini_set('memory_limit', '2048M');
set_time_limit(0);
include("include/conexion.php");
require_once 'include/PHPExcel/Classes/PHPExcel.php';
require_once 'include/PHPExcel/Classes/PHPExcel/IOFactory.php';
$objPHPExcel = new PHPExcel();
$objPHPExcel->getProperties()->setCreator("Name")
->setLastModifiedBy("Name")
->setTitle("Listado")
->setSubject("Listado")
->setDescription("Listado.")
->setKeywords("Listado")
->setCategory("Listado");
$activeSheet = $objPHPExcel->getActiveSheet();
$query = explode("|",stripcslashes($_POST['query']));
$activeSheet->setTitle('List');
$resEmp = mysql_query ($query, $conexion ) or die(mysql_error());
$tot = mysql_num_rows($resEmp);
$num_fields = mysql_num_fields($resEmp);
$fistIndex = $activeSheet->getCellByColumnAndRow(0, 1)->getColumn();
$lastIndex = $activeSheet->getCellByColumnAndRow($num_campos - 1, 1)->getColumn();
//tittles
for ($e=0;$e < $num_fields;$e++){
$activeSheet->setCellValueByColumnAndRow($e, 2, utf8_decode(ucwords(mysql_field_name($resEmp,$e))));
$activeSheet->getColumnDimension($activeSheet->getCellByColumnAndRow($e, 2)->getColumn())->setAutoSize(true);
}
//color tittles
$activeSheet->getStyle( $fistIndex.'1:'.$lastIndex.'2' )->getFill()->setFillType(PHPExcel_Style_Fill::FILL_SOLID)->getStartColor()->setRGB('c5c5c7');
$activeSheet->getStyle( $fistIndex.'1:'.$lastIndex.'2' )->getFont()->setBold(true);
if(isset ( $_POST ['mail'] )){
$activeSheet->setCellValueByColumnAndRow(0, 2, "Email");
$emails = array();
for ($row = 0; $row < $totEmp; $row++) {
//more than one mail in field separated by ";"
$aux = explode(";", mysql_result($resEmp,$row,$col));
for($i=0; $i<count($aux); $i++){
$cleaned = utf8_encode(strtolower(trim($aux[$i])));
//filter repeated mails
if(!in_array($cleaned, $emails) && $aux[$i] != ""){
array_push($emails, $cleaned);
}
}
}
for ($row = 0; $row < count($emails); $row++) {
$activeSheet->setCellValueByColumnAndRow(0, $row + 3, $emails[$row]);
}
}
$objWriter = PHPExcel_IOFactory::createWriter($objPHPExcel, 'Excel2007');
header('Content-type: application/vnd.ms-excel');
header("Content-Disposition: attachment; filename=".$nom_archivo.".xlsx");
// Write file to the browser
$objWriter->save('php://output');
exit();
?>

Answer 1

Seems this library has serious problem in parsing large excel spreadsheets, I'd this issue already & I couldn't find a proper solution. I guess this is normal behaviour because this library is written fully in PHP that causes a lot of parsing overhead.
I strongly suggest you to use a excel parsing PHP-extension like this one.
As another thinkable solution [if its possible], you can break down your big file to several smaller files (e.g by sheets), otherwise I guess you should use a faster CPU or use another library or programming language to parse your exel files (e.g. apache-poi in java, maybe with a PHP/Java bridge).

Answer 2

Unfortunately, PHPExcel is not good for performing with large data because PHP is not really a good binary file processing language.
Some people export their data to XML format of excel (http://en.wikipedia.org/wiki/Microsoft_Office_XML_formats) and it can work well. However, the xml format does not have full features of excel binary file and of course it will have a bigger file size.
In order to work with the large data (import/export to binary excel file), our system now using libxl which will cost you 199$ for a license, and php_excel which is a wrapper for libxl. In effect, our system now export a excel file with more than 5k of rows in about just only some seconds using libxl and I think it's an only solution for you until now to use binary excel.
P/s: The $objPHPExcel->getActiveSheet() also have a cost, so you could store it value to a variable for reusing later which will help you to speed up your code a little bit.

Answer 3

I had this problem but after changed some options in php.ini and scripts, I could reduce file from 28 MB to 4 MB.
increase memory_limit=2048M in php.ini.
change max_execution_time to more seconds.
in the script yo should use Excel2007 like below:
ob_end_clean();
header('Content-Type: application/vnd.ms-excel');
header("Content-Disposition: attachment;filename=$date.xls");
header('Cache-Control: max-age=0');
ob_end_clean();
$objWriter =PHPExcel_IOFactory::createWriter($objPHPExcel, 'Excel2007');
$objWriter->save('php://output');