ds342222 2017-04-20 20:22
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如何在PHP只有1 GB内存的虚拟专用服务器上迭代4GB CSV文件?

So my case is like this:

I do have a CSV 4GB comma separated value file and my virtual private server has only 1 GB of memory dedicated to PHP.

My question is this:

Is there any way to allocate memory for only one CSV row at a time instead of reading the entire 4GB file into memory?

Example code:

<?php
function getRows($file){
    $handle = fopen($file, 'rb');
    if($handle === false){
        throw new Exception();
    }
    while(feof($handle)===false){
        $line_of_txt=fgetcsv($handle);
    }
    fclose($handle);
    return $line_of_txt;
}
foreach(getRows('DWBankStatmentApril.csv') as $row){
    print_r($row);
}
?>
  • 写回答

1条回答 默认 最新

  • donglu7286 2017-04-22 22:52
    关注

    Got it right now.

     <?php
    function getRows($file){
        $handle = fopen($file, 'rb');
        if($handle === false){
            throw new Exception();
        }
        while(feof($handle)===false){
            yield=fgetcsv($handle);
        }
        fclose($handle);
    
    }
    foreach(getRows('DWBankStatmentApril.csv') as $row){
        print_r($row);
    }
    ?>
    

    The issue was solved by using a generator instead, they are mainly used for forward-only interating large data sets with a tiny amount of system memory.

    本回答被题主选为最佳回答 , 对您是否有帮助呢?
    评论

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