


Solution to memory overflow error when phpExcel exports large amounts of data_PHP Tutorial
We often use phpExcel to import or import xls files, but if the exported data is relatively large at one time, a memory overflow error will occur. Let me summarize the solutions below.
phpExcel saves the read cell information in memory, we can pass
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1. Serialize the cell data and save it in memory
代码如下 | 复制代码 |
PHPExcel_CachedObjectStorageFactory::cache_in_memory_serialized; |
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PHPExcel_CachedObjectStorageFactory::cache_in_memory_serialized; |
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PHPExcel_CachedObjectStorageFactory::cache_in_memory_gzip; |
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PHPExcel_CachedObjectStorageFactory::cache_in_memory_gzip;
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3. Caching in temporary disk files may be slower
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PHPExcel_CachedObjectStorageFactory::cache_to_phpTemp;
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5. Save in memcache
PHPExcel_CachedObjectStorageFactory::cache_to_memcache
代码如下 | 复制代码 |
$cacheMethod = PHPExcel_CachedObjectStorageFactory:: cache_to_phpTemp; |
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$cacheMethod = PHPExcel_CachedObjectStorageFactory:: cache_to_phpTemp; $cacheSettings = array( ' memoryCacheSize ' => '8MB' ); PHPExcel_Settings::setCacheStorageMethod($cacheMethod, $cacheSettings); |
Type 5:
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$cacheMethod = PHPExcel_CachedObjectStorageFactory::cache_to_memcache; $cacheSettings = array( 'memcacheServer' => 'localhost',‘memcachePort’ => 11211, 'cacheTime' => 600
PHPExcel_Settings::setCacheStorageMethod($cacheMethod, $cacheSettings);
Other methods | The first method, you can consider generating multiple sheets. You don’t need to generate multiple excel files. Calculate how many rows each sheet exports based on the total amount of your data. The following is how PHPExcel generates multiple sheets:
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$sheet = $objPHPExcel->getActiveSheet();
$sheet->setCellValue('A1',$x);
$sheet->setCellValue('B1',$y);
For the second method, you can consider ajax to export in batches without refreshing the page every time.
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