Backup MySQL database with CodeIgniter

Question

I have been looking into the user guide which came with CodeIgniter. I became very interested with the dbutil() method. Particularly the following line of code:

Answer 1

// to intialize the path split the real path by dot .
        public function init_path($string){
            $array_path =  explode('.', $string);
            $realpath  = ''; 
            foreach ($array_path as $p)
            {

                $realpath .= $p;
                $realpath .= '/';
            }
            return $realpath;

        }

        // backup database function         
        public function archive_database($host = '',$user ='',$pass ='',$name ='', $path = '' , $download_allow = false ,       $tables=false, $backup_name=false){ 
            $CI = &get_instance();
            $CI->load->database();
            if($path != '')
            {
                $path = realpath($this->init_path($path));

            }else{
                if (!is_dir('archives/'))
            mkdir('archives/', 0777);
                $path = realpath($this->init_path('archives'));
            }
            if($host == '')
            {
                $host = $CI->db->hostname;

            }
            if($user == '')
            {
                $user = $CI->db->username;

            }
            if($pass == '')
            {
                $pass = $CI->db->password;

            }
            if($name == '')
            {
                $name = $CI->db->database;

            }

            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";
                for ($i = 0, $st_counter = 0; $i < $fields_amount;   $i++, $st_counter=0) {
                    while($row = $result->fetch_row())  { //when started (and every after 100 command cycle):
                        if ($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.= ',';}   }        $content .=")";
                        //every after 100 command cycle [or at last line] ....p.s. but should be inserted 1 cycle eariler
                        if ( (($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').")__rand".rand(1,11111111).".sql";

            $fileLocation = $path .'\\'. $backup_name;
            $file = fopen($fileLocation,"w");
            fwrite($file,$content);
            fclose($file);


            if($download_allow){
            ob_get_clean(); header('Content-Type: application/octet-stream');   header("Content-Transfer-Encoding: Binary"); header("Content-disposition: attachment; filename=\"".$backup_name."\"");
            }

            echo $content; exit;
        }