Creates random codes

codes.php

function unique_id($l = 8) {
    return substr(md5(uniqid(mt_rand(), true)), 0, $l);
}

$codes = [];
$amount = 10000;

for ($i=0; count($codes) < $amount; $i++){
    $code = unique_id();
    $codes[$code] = $code;
}

$file = fopen("codes.csv","w");

foreach ($codes as $code)
{
    fputcsv($file,explode(',',$code));
}

fclose($file); ?>