$host="localhost";
  

  $user="root";
  

  $password="";
  

  $dbname="dbname";
  

  

  mysql_connect($host,$user,$password);
  

  mysql_select_db($dbname);
  

  $mysql= "set names utf8;";
  

  mysql_query($mysql);
  

  $q1=mysql_query("show tables");
  

  while($t=mysql_fetch_array($q1)){
  

  $table=$t[0];
  

  $q2=mysql_query("show create table `$table`");
  

  $sql=mysql_fetch_array($q2);
  

  $mysql.=$sql['Create Table'].";\n";
  

  

  $q3=mysql_query("select * from `$table`");
  

  while($data=mysql_fetch_assoc($q3)){
  

  $keys=array_keys($data);
  

  $keys=array_map('addslashes',$keys);
  

  $keys=join('`,`',$keys);
  

  $keys="`".$keys."`";
  

  $vals=array_values($data);
  

  $vals=array_map('addslashes',$vals);
  

  $vals=join("','",$vals);
  

  $vals="'".$vals."'";
  

  $mysql.="insert into `$table`($keys) values($vals);\n";
  

  }
  

  $mysql.="\n";
  

  }
  

  $filename=date('Ymj').".sql";
  

  $fp = fopen($filename,'w');
  

  fputs($fp,$mysql);
  

  fclose($fp);
  

  echo "数据备份成功,生成备份文件".$filename;