如何使用代码点火器“dbutil”类备份另一个数据库

我以前没有使用过 dbutil 类，但你不能在配置/数据库文件中添加新数据库并加载它吗？

$db['new_db_name']['hostname'] = "localhost"; // localhost if same server
$db['new_db_name']['username'] = "un"; // your db username
$db['new_db_name']['password'] = 'pass'; // your db password
$db['new_db_name']['database'] = "new_db_name"; // your db name
$db['new_db_name']['dbdriver'] = "mysql";
$db['new_db_name']['dbprefix'] = "";
$db['new_db_name']['pconnect'] = TRUE;
$db['new_db_name']['db_debug'] = TRUE;
$db['new_db_name']['cache_on'] = FALSE;
$db['new_db_name']['cachedir'] = "";
$db['new_db_name']['char_set'] = "utf8";
$db['new_db_name']['dbcollat'] = "utf8_general_ci";

然后$this->加载>数据库（'new_db_name'）;

/任何 dbutil 函数...

编辑：我刚刚对此进行了测试，似乎 dbutil 类使用 $this->db 对象。因此，如果您将 $this->load->database('new_db_name', TRUE) 的结果设置为 $this->db（第二个"TRUE"参数以返回 db 对象），那么它可以工作，即：

$this->db = $this->load->database('new_db_name', TRUE);
$this->load->dbutil();
// do whatever

您还可以将另一个数据库对象传递给数据库实用程序加载程序，以防您要管理的数据库不是默认数据库：$this->myutil = $this->load->dbutil（$this->other_db， TRUE）;

例：

$this->other_db = $this->load->database('other_db', TRUE);       
 $this->myutil = $this->load->dbutil($this->other_db, TRUE);
            $prefs = array(
                'format' => 'zip',
                'filename' => $file_name . '.sql'
            );
            $backup = $this->myutil->backup($prefs);
            $db_name = 'backup-on-' . date("Y-m-d-H-i-s") . '.zip';
            $save = './assets/backups/' . $folder . '/' . $db_name;
            $this->load->helper('file');
            write_file($save, $backup);
            echo 'Done...';

试试这段代码

<?php 
 class Backup extends CI_Controller
{
   public function __construct()
{
       parent::__construct();
           $this->load->database();   // Loads the database setting 
    }
   public function backup_db()
   {
             /* Store All Table name in an Array */

     $return="";
     $allTables = array();
             $result = mysql_query('SHOW TABLES');
            while($row = mysql_fetch_row($result))
            {
                                                     $allTables[] = $row[0];
                            }
            foreach($allTables as $table)
            {
                $result = mysql_query('SELECT * FROM '.$table);
                $num_fields = mysql_num_fields($result);
                $return.= 'DROP TABLE IF EXISTS '.$table.';';
                $row2 = mysql_fetch_row(mysql_query('SHOW CREATE TABLE '.$table));
                $return.= "'n'n".$row2[1].";'n'n";
                for ($i = 0; $i < $num_fields; $i++) 
                    {
                            while($row = mysql_fetch_row($result))
                            {
                                $return.= 'INSERT INTO '.$table.' VALUES(';
                                    for($j=0; $j<$num_fields; $j++)
                                        {
                                            $row[$j] = addslashes($row[$j]);
                                                $row[$j] = str_replace("'n","''n",$row[$j]);
                                                if (isset($row[$j])) { $return.= '"'.$row[$j].'"' ; } 
                                                else { $return.= '""'; }
                                                if ($j<($num_fields-1)) { $return.= ','; }
                                        }
                                $return.= ");'n";
                            }
                    }
$return.="'n'n";
}// Create Backup Folder
         $folder = 'Database_Backup/';
         if (!is_dir($folder))
            mkdir($folder, 0755, true);
            chmod($folder, 0755);
            $date = date('m-d-Y-H-i-s', time()); 
            $filename = $folder."Medi_Hospi-".$date; 
            $handle = fopen($filename.'.sql','w+');
        fwrite($handle,$return);
            fclose($handle);
       echo "Backup of Database Taken";
 }
}    ?>