دریافت بکاپ از mysql با php

<?php
// Database configuration
$host = "localhost";
$username = "root";
$password = "";
$database_name = "mydatabasename";
// Get connection object and set the charset
$conn = mysqli_connect($host, $username, $password, $database_name);
$conn->set_charset("utf8");
// Get All Table Names From the Database
$tables = array();
$sql = "SHOW TABLES";
$result = mysqli_query($conn, $sql);
while ($row = mysqli_fetch_row($result)) {
$tables[] = $row[0];
}
$sqlScript = "";
foreach ($tables as $table) {
// Prepare SQLscript for creating table structure
$query = "SHOW CREATE TABLE $table";
$result = mysqli_query($conn, $query);
$row = mysqli_fetch_row($result);
$sqlScript .= "\n\n" . $row[1] . ";\n\n";
$query = "SELECT * FROM $table";
$result = mysqli_query($conn, $query);
$columnCount = mysqli_num_fields($result);
// Prepare SQLscript for dumping data for each table
for ($i = 0; $i < $columnCount; $i ++) {
while ($row = mysqli_fetch_row($result)) {
$sqlScript .= "INSERT INTO $table VALUES(";
for ($j = 0; $j < $columnCount; $j ++) {
$row[$j] = $row[$j];
if (isset($row[$j])) {
$sqlScript .= '"' . $row[$j] . '"';
} else {
$sqlScript .= '""';
}
if ($j < ($columnCount - 1)) {
$sqlScript .= ',';
}
}
$sqlScript .= ");\n";
}
}

$sqlScript .= "\n";
}

if(!empty($sqlScript))
{
// Save the SQL script to a backup file
$backup_file_name = $database_name . '_backup_' . time() . '.sql';
$fileHandler = fopen($backup_file_name, 'w+');
$number_of_lines = fwrite($fileHandler, $sqlScript);
fclose($fileHandler);
// Download the SQL backup file to the browser
header('Content-Description: File Transfer');
header('Content-Type: application/octet-stream');
header('Content-Disposition: attachment; filename=' . basename($backup_file_name));
header('Content-Transfer-Encoding: binary');
header('Expires: 0');
header('Cache-Control: must-revalidate');
header('Pragma: public');
header('Content-Length: ' . filesize($backup_file_name));
ob_clean();
flush();
readfile($backup_file_name);
exec('rm ' . $backup_file_name);
}
?>