[php] How to backup MySQL database in PHP?

try this 100% working.

<?php
function dbbackup($host,$user,$pass,$name,$tables=false, $backup_name=false)
{ 
set_time_limit(3000); 
$mysqli = new mysqli($host,$user,$pass,$name); 
$mysqli->select_db($name); 
$mysqli->query("SET NAMES 'utf8'");
$queryTables = $mysqli->query('SHOW TABLES'); 
while($row = $queryTables->fetch_row()) 
{ 
    $target_tables[] = $row[0]; 
}   
if($tables !== false) 
{
    $target_tables = array_intersect( $target_tables, $tables); 
} 
$content = "SET SQL_MODE = \"NO_AUTO_VALUE_ON_ZERO\";\r\nSET time_zone = \"+00:00\";\r\n\r\n\r\n/*!40101 SET @OLD_CHARACTER_SET_CLIENT=@@CHARACTER_SET_CLIENT */;\r\n/*!40101 SET @OLD_CHARACTER_SET_RESULTS=@@CHARACTER_SET_RESULTS */;\r\n/*!40101 SET @OLD_COLLATION_CONNECTION=@@COLLATION_CONNECTION */;\r\n/*!40101 SET NAMES utf8 */;\r\n--\r\n-- Database: `".$name."`\r\n--\r\n\r\n\r\n";
foreach($target_tables as $table)
{
    if (empty($table))
    {
        continue;
    } 
    $result = $mysqli->query('SELECT * FROM `'.$table.'`');     $fields_amount=$result->field_count;  $rows_num=$mysqli->affected_rows;     $res = $mysqli->query('SHOW CREATE TABLE '.$table); $TableMLine=$res->fetch_row(); 
    $content .= "\n\n".$TableMLine[1].";\n\n";   $TableMLine[1]=str_ireplace('CREATE TABLE `','CREATE TABLE IF NOT EXISTS `',$TableMLine[1]);
    for ($i = 0, $st_counter = 0; $i < $fields_amount;   $i++, $st_counter=0) 
    {
        while($row = $result->fetch_row())  
        {
            if ($st_counter%100 == 0 || $st_counter == 0 )  
            {
                $content .= "\nINSERT INTO ".$table." VALUES";
            }
            $content .= "\n(";    
            for($j=0; $j<$fields_amount; $j++)
            {
                $row[$j] = str_replace("\n","\\n", addslashes($row[$j]) ); 
                if (isset($row[$j]))
                {
                    $content .= '"'.$row[$j].'"' ;
                } 
                else
                {
                    $content .= '""';
                }
                if ($j<($fields_amount-1))
                {
                    $content.= ',';
                }  
            }
            $content .=")";
            if ( (($st_counter+1)%100==0 && $st_counter!=0) || $st_counter+1==$rows_num) 
            {
                $content .= ";";
            }
            else
            {
                $content .= ",";
            }
            $st_counter=$st_counter+1;
        }
    } $content .="\n\n\n";
}
$content .= "\r\n\r\n/*!40101 SET CHARACTER_SET_CLIENT=@OLD_CHARACTER_SET_CLIENT */;\r\n/*!40101 SET CHARACTER_SET_RESULTS=@OLD_CHARACTER_SET_RESULTS */;\r\n/*!40101 SET COLLATION_CONNECTION=@OLD_COLLATION_CONNECTION */;";
$backup_name = $backup_name ? $backup_name : $name.'___('.date('H-i-s').'_'.date('d-m-Y').').sql';
ob_get_clean(); 
header('Content-Type: application/octet-stream'); 
header("Content-Transfer-Encoding: Binary"); 
header('Content-Length: '. (function_exists('mb_strlen') ? mb_strlen($content, '8bit'): strlen($content)) );   
header("Content-disposition: attachment; filename=\"".$backup_name."\""); 
echo $content; exit;
}
dbbackup("host", "user", "password", "database" );
?>

check on github