PHP - 将大型CSV解析成数组数组 - 内存大小耗尽 [英] PHP - parse large CSV into array of arrays - memory size exhausted

问题描述

我想请求帮助这个任务：
我有大的CSV：680列x 1300行，我需要解析按列（我需要有数组

 <$ c $ 
 c> $ input =data / input.csv; 
 
 if（（$ handle = fopen（$ input，r））！== false）{
 $ filesize = filesize（$ input）; 
 while（（$ data = fgetcsv（$ handle，$ filesize，$））！== false）{
 for（$ i = 0; $ i< count（$ data）; $ i ++）{
 $ this-> columns [$ i] [] = $ data [$ i]; 
} 
} 
 fclose（$ handle）;问题是，我收到此错误
 
  
 致命错误：允许在第72行的/www/classes/Analyser.php中耗尽134217728字节（尝试分配16384字节）的内存大小
 
 
 
第72行是 $ this-> columns [$ i] [] = $ data [$ i];  
 
 
 
不允许我增加内存限制。有没有办法有效地编写代码，所以没有必要这么多的内存，或者只是这么大的CSV的问题？
 
 
 
感谢大家。 p> 
 
解决方案
 
  function analyze_column（$ column）{
 // b $ b return $ the_results; 
} 
 
 $ a = 0; 
 $ results = array（）; 
 
 while（$ a< COUNT_OF_COLUMNS）{
 $ column = Array（）; 
 while（（$ data = fgetcsv（$ handle，$ filesize，$））！== false）{
 array_push（$ column，$ data [$ a]）; 
} 
 
 $ results [] = analyze_column（$ column）; 
 
 $ a ++; 
} 
  
 
I would like to ask for help with this task:
I have large CSV: 680 columns x 1300 rows and I need to parse it by columns (I need to have array of arrays of column values).

I use this code for this:
$input = "data/input.csv";

    if (($handle = fopen($input, "r")) !== false) {
        $filesize = filesize($input);
        while (($data = fgetcsv($handle, $filesize, "$")) !== false) {
            for ($i = 0; $i < count($data); $i++) {
                $this->columns[$i][] = $data[$i];
            }
        }
        fclose($handle);
Problem is, that I get this error

Fatal error: Allowed memory size of 134217728 bytes exhausted (tried to allocate 16384 bytes) in /www/classes/Analyser.php on line 72 

line 72 is $this->columns[$i][] = $data[$i];

My hosting does not allow me to increase the memory limit. Is there a way to write the code efficiently, so there is no need for so much memory, or is it just problem of such large CSV?

Thanks everyone.
解决方案
function analyze_column($column) {
    // do your work here
    return $the_results;
}

$a = 0;
$results = array();

while ($a < COUNT_OF_COLUMNS) {
    $column = Array();
    while (($data = fgetcsv($handle, $filesize, "$")) !== false) {
        array_push($column,$data[$a]);
    }

    $results[] = analyze_column($column);

    $a++;
}


                        
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