exporting large files to excel using PHPExcel - php

Question

I am trying to export around 40,000 rows of Mysql data in PHP(Laravel4) using PHPExcel library.
Below is my code:
($patList is an array of result columns)
set_time_limit ( 3000 );
$cacheMethod = PHPExcel_CachedObjectStorageFactory:: cache_to_phpTemp;
$cacheSettings = array( 'memoryCacheSize' => -1);
PHPExcel_Settings::setCacheStorageMethod($cacheMethod, $cacheSettings);
$objPHPExcel = new PHPExcel();
$i = 1;
$patList = $result[0];
for ($r = 0; $r < count($patList); $r++) {
$objPHPExcel->setActiveSheetIndex(0)
->setCellValue("A$i", $patList[$r][0])
->setCellValue("B$i", $patList[$r][1])
->setCellValue("C$i", $patList[$r][2])
->setCellValue("D$i", $patList[$r][1])
->setCellValue("E$i", $patList[$r][2])
->setCellValue("F$i", $patList[$r][1])
->setCellValue("G$i", $patList[$r][2])
->setCellValue("H$i", $patList[$r][2])
->setCellValue("I$i", $patList[$r][1])
->setCellValue("J$i", $patList[$r][2])
->setCellValue("K$i", $patList[$r][5]);
$i++;
}
$objPHPExcel->getActiveSheet()->setTitle('Name of Sheet 1');
header('Content-Type: application/vnd.ms-excel');
header('Content-Disposition: attachment;filename="result.xls"');
header('Cache-Control: max-age=0');
ob_clean();
flush();
$objWriter = PHPExcel_IOFactory::createWriter($objPHPExcel, 'Excel5');
$objWriter->save('php://output');
The above code runs fine if there are 3-4 columns in the excel and 15,000 rows. However, if I increase the no. of rows to 30,000 or the no. of columns to 10, the excel doesn't get generated.

Answer 1

$cacheSettings = array( 'memoryCacheSize' => -1);
isn't sensible.... I don't even know if using a value of -1 will work; but if it does, it will mean that you're storing everything in memory and nothing in php://temp
The memoryCacheSize value tells the cache stream how much data should be stored in memory before switching data out to php://temp ; so
$cacheSettings = array( 'memoryCacheSize' => '8MB');
would tell the cache stream to use 8MB of memory, and then if additional data needed to be stored to use php://temp instead