<?php    
    $host="localhost";              
$user="root";          
$password="";            
$dbname="";          
mysql_connect($host,$user,$password);              
mysql_select_db($dbname);            
$mysql= "set charset utf8;rn";                
$q1=mysql_query("show tables");                
while($t=mysql_fetch_array($q1)){          
    $table=$t[0];          
    $q2=mysql_query("show create table `$table`");                
    $sql=mysql_fetch_array($q2);            
    $mysql.=$sql['Create Table'].";rnrn";            
          
    $q3=mysql_query("select * from `$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);rn";          
    }          
    $mysql.="rn";                        
}          
$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."";    
?>