Processing a big php file. Rewrite column values

[gionna]

I'm trying to solve the challenge of handling the big csv File (12194 line) with goods, reading the file with a library https://github.com/parsecsv/parsecsv-for-php

There's a model code in the file, I need to go through every line and add an early prefix to the model code, for example: MODELCODE_PREF987To this end, I write this code using the library methods:

  <?php
    set_time_limit(0);
    require_once('parsecsv.lib.php');
$fileCSV = 'file_pred.csv';

$csv = new parseCSV();
$csv-&gt;delimiter = "\t";
$csv-&gt;parse($fileCSV);

$count = count($csv-&gt;data);

for($i = 0; $i&lt;$count; $i++){
        $ID = $csv-&gt;data[$i]['Код модели'] . "_" . rand(0,1000);    
        $csv-&gt;data[$i]['Код модели'] = $ID;
        $csv-&gt;save(); 
} 

But the violin depends on data modifications, if it's just a conclusion, it works fast. And most likely, php I'm just starting to figure out, so my code is probably wrong. Please provide an example.
(complete to the compendium) record method

 protected function _wfile($file, $string = '', $mode = 'wb', $lock = 2) {

if ($fp = fopen($file, $mode)) {

flock($fp, $lock);

$re = fwrite($fp, $string);

$re2 = fclose($fp);

        if ($re != false && $re2 != false) {
            return true;
        }
    }

    return false;
}

[esther]

Try to bear it. $csv->save() cycle for():

//...
for($i = 0; $i<$count; $i++){
    $ID = $csv->data[$i]['Код модели'] . "_" . rand(0,1000);    
    $csv->data[$i]['Код модели'] = $ID;
} 
$csv->save(); 

You're making it seem that after every change, there's a file going on, and it's enough to keep the file once, at the end, after all the changes are taken into account. I didn't work with this library, but I watched the library code on the guitar and I think it should help.