php mysql รบกวนสอบถาม การเขียนตัว backup mysql data และ restore mysql data ครับ

<?php
/*
 * Restore MySQL dump using PHP
 * (c) 2006 Daniel15
 * Last Update: 9th December 2006
 * Version: 0.2
 * Edited: Cleaned up the code a bit. 
 *
 * Please feel free to use any part of this, but please give me some credit <img src="/images/bbcode/smile.gif?v=1001" align="absmiddle">
 */
  
// Name of the file
$filename = 'test.sql';
// MySQL host
$mysql_host = 'localhost';
// MySQL username
$mysql_username = 'root';
// MySQL password
$mysql_password = '1234';
// Database name
$mysql_database = 'tb';
 
//////////////////////////////////////////////////////////////////////////////////////////////
 
// Connect to MySQL server
mysql_connect($mysql_host, $mysql_username, $mysql_password) or die('Error connecting to MySQL server: ' . mysql_error());
// Select database
mysql_select_db($mysql_database) or die('Error selecting MySQL database: ' . mysql_error());
 
// Temporary variable, used to store current query
$templine = '';
// Read in entire file
$lines = file($filename);
// Loop through each line
foreach ($lines as $line)
{
    // Skip it if it's a comment
    if (substr($line, 0, 2) == '--' || $line == '')
        continue;
 
    // Add this line to the current segment
    $templine .= $line;
	
    // If it has a semicolon at the end, it's the end of the query
    if (substr(trim($line), -1, 1) == ';')
    {
        // Perform the query
        mysql_query($templine) or print('Error performing query \'<strong>' . $templine . '\': ' . mysql_error() . '</strong><br />');
        // Reset temp variable to empty
        $templine = '';
    }
}
?>

##################### 
//CONFIGURATIONS  
#####################
// Define the name of the backup directory
define('BACKUP_DIR', './myBackups' ) ; 
// Define  Database Credentials
define('HOST', $host ) ; 
define('USER', $username ) ; 
define('PASSWORD', $pw ) ; 
define('DB_NAME', $db ) ; 
/*
Define the filename for the sql file
If you plan to upload the  file to Amazon's S3 service , use only lower-case letters 
*/
$fileName = 'mysqlbackup--' . date('d-m-Y') . '@'.date('h.i.s').'.sql' ; 
// Set execution time limit
if(function_exists('max_execution_time')) {
if( ini_get('max_execution_time') > 0 ) 	set_time_limit(0) ;
}

###########################  

//END  OF  CONFIGURATIONS  

###########################

// Check if directory is already created and has the proper permissions
if (!file_exists(BACKUP_DIR)) mkdir(BACKUP_DIR , 0700) ;
if (!is_writable(BACKUP_DIR)) chmod(BACKUP_DIR , 0700) ; 

// Create an ".htaccess" file , it will restrict direct accss to the backup-directory . 
/*
$content = 'deny from all' ; 
$file = new SplFileObject(BACKUP_DIR . '/.htaccess', "w") ;
$file->fwrite($content) ;
*/

$mysqli = new mysqli(HOST , USER , PASSWORD , DB_NAME) ;

//– Set MySQLi Charset to UTF-8 (support Thai Language)
$mysqli->set_charset("utf8");

/* change character set to utf8 */
/*
if (!$mysqli->set_charset("utf8")) {
    printf("Error loading character set utf8: %s\n", $mysqli->error);
} else {
    printf("Current character set: %s\n", $mysqli->character_set_name());
}
*/

if (mysqli_connect_errno())
{
   printf("Connect failed: %s", mysqli_connect_error());
   exit();
}
 // Introduction information
 $return .= "--\n";
$return .= "-- A Mysql Backup System \n";
$return .= "--\n";
$return .= '-- Export created: ' . date("Y/m/d") . ' on ' . date("h:i") . "\n\n\n";
$return = "--\n";
$return .= "-- Database : " . DB_NAME . "\n";
$return .= "--\n";
$return .= "-- --------------------------------------------------\n";
$return .= "-- ---------------------------------------------------\n";
$return .= 'SET AUTOCOMMIT = 0 ;' ."\n" ;
$return .= 'SET FOREIGN_KEY_CHECKS=0 ;' ."\n" ;
$tables = array() ; 

// Exploring what tables this database has
$result = $mysqli->query('SHOW TABLES' ) ;

// Cycle through "$result" and put content into an array
while ($row = $result->fetch_row()) 
{
$tables[] = $row[0] ;
}
// Cycle through each  table
 foreach($tables as $table)
 { 
// Get content of each table
$result = $mysqli->query('SELECT * FROM '. $table) ; 
// Get number of fields (columns) of each table
$num_fields = $mysqli->field_count  ;
// Add table information
$return .= "--\n" ;
$return .= '-- Tabel structure for table `' . $table . '`' . "\n" ;
$return .= "--\n" ;
$return.= 'DROP TABLE  IF EXISTS `'.$table.'`;' . "\n" ; 
// Get the table-shema
$shema = $mysqli->query('SHOW CREATE TABLE '.$table) ;
// Extract table shema 
$tableshema = $shema->fetch_row() ; 
// Append table-shema into code
$return.= $tableshema[1].";" . "\n\n" ; 
// Cycle through each table-row
while($rowdata = $result->fetch_row()) 
{ 
// Prepare code that will insert data into table 
$return .= 'INSERT INTO `'.$table .'`  VALUES ( '  ;
// Extract data of each row 
for($i=0; $i<$num_fields; $i++)
{
$return .= '"'.$rowdata[$i] . "\"," ;
 }
 // Let's remove the last comma 
 $return = substr("$return", 0, -1) ; 
 $return .= ");" ."\n" ;
 } 
 $return .= "\n\n" ; 
}
// Close the connection
$mysqli->close() ;
$return .= 'SET FOREIGN_KEY_CHECKS = 1 ; '  . "\n" ; 
$return .= 'COMMIT ; '  . "\n" ;
$return .= 'SET AUTOCOMMIT = 1 ; ' . "\n"  ; 

$fsave=@fopen("myBackups/".$fileName,"w");
		fwrite($fsave,$return);
		fclose($fsave);

//Class Dzip
	$ZipName = "myBackups/".$fileName.".zip";
	require_once("lib/dZip.inc.php"); // include Class
	$zip = new dZip($ZipName); // New Class
	$zip->addFile("myBackups/".$fileName, $fileName); // Source,Destination
	$zip->save();
	//echo "Zip Successful Click <a href=".$ZipName.">here</a> to Download";
		
//$file = file_put_contents($fileName , $return) ; 
/*
$zip = new ZipArchive() ;
$resOpen = $zip->open(BACKUP_DIR . '/' .$fileName.".zip" , ZIPARCHIVE::CREATE) ;
if( $resOpen ){
$zip->addFromString( $fileName , "$return" ) ;
    }
$zip->close() ;
*/
$fileSize = get_file_size_unit(filesize(myBackups . "/". $fileName . '.zip')) ;
	@unlink("myBackups/".$fileName);
$message = "
  <h2>สำรองข้อมูลเสร็จเรียบร้อย</h2>
 <br />
  ชื่อไฟล์ที่สำรองข้อมูลคือ  : <b>  <a href=\"myBackups/".$fileName.".zip\">".$fileName."</a>  </b> 
  <br />
  และมีขนาดของไฟล์คือ :   ".$fileSize." 
  ";
echo $message ; 

	
}else{
echo "<form name=\"frmbackup\" action=\"\" method=\"post\" enctype=\"multipart/form-data\">";
		echo "<input type=\"submit\" name=\"btnok\" value=\"สำรองข้อมูล\" onclick=\"return confirm('ระบบจะทำการสำรองฐานข้อมูล ยืนยันทำรายการ ?');\" />";
	echo "</form>";
}
// Function to append proper Unit after file-size . 
	function get_file_size_unit($file_size){
		switch (true) {
			case ($file_size/1024 < 1) :
				return intval($file_size ) ." Bytes" ;
				break;
			case ($file_size/1024 >= 1 && $file_size/(1024*1024) < 1)  :
				return intval($file_size/1024) ." KB" ;
				break;
			default:
			return intval($file_size/(1024*1024)) ." MB" ;
		}
	}