<?php
$host = '192.168.33.38';
$username = 'root';
$password = 'Ehu4t/aDifyMNUZy';
$dbname = 'demo';

$conn = mysqli_connect($host, $username, $password);
if (!$conn) {
    die("Unable to connect to db " . mysqli_connect_error());
}
if (!mysqli_select_db($conn, $dbname)) {
    die("Unable to select db " . mysqli_connect_error());
}

$number_of_records = 1000000;
$records_per_bundle = 1000;
$card_types = ['visa', 'master'];
$j = $records_per_bundle;
$sql = "INSERT INTO `credit_cards`(`type`, `number`, `exp_month`, `exp_year`, `cvv`, `modified_at`) VALUES ";
for ($i = 1; $i <= $number_of_records; $i++) {
    $card_type = $card_types[rand(0, 1)];
    $card_number = '';
    if ($card_type === 'visa') {
        $card_number = rand(4000, 4999);
    } else {
        $card_number = rand(5000, 5999);
    }
    $t = 0;
    while ($t < 3) {
        $num = rand(0000, 9999);
        if ($num < 100) {
            $num = "{$num}00";
        } else if ($num < 1000) {
            $num = "{$num}0";
        }
        $card_number .= "-" . $num;
        $t++;
    }
    $card_exp_month = rand(1, 12);
    if ($card_exp_month < 10) {
        $card_exp_month = "0$card_exp_month";
    }
    $card_exp_year = rand(17, 99);
    $card_cvv = rand(000, 999);
    $card_modified_at = date('Y-m-d H:i:s');
    $sql .= "('$card_type', '$card_number', '$card_exp_month', '$card_exp_year', '$card_cvv', '$card_modified_at')";
    $j--;
    if ($j === 0) {
        $sql .= ';';
        if (!mysqli_query($conn, $sql)) {
            die("Unable to perform query. " . mysqli_error($conn));
        }
        echo "Proceed: $i   \r";

        $j = $records_per_bundle;
        $sql = "INSERT INTO `credit_cards`(`type`, `number`, `exp_month`, `exp_year`, `cvv`, `modified_at`) VALUES ";
    } else {
        $sql .= ',';
    }
}

mysqli_close($conn);
?>