PHP实现数据库备份定时任务的方法

$mysqli = new mysqli(DB_HOST, DB_USER, DB_PASS, DB_NAME);
if($mysqli->connect_errno)
{
    die("Failed to connect: " . $mysqli->connect_error);
}

$tables = array();  
$result = $mysqli->query('SHOW TABLES');
while($row = $result->fetch_row())  
{  
     $tables[] = $row[0];  
}

foreach($tables as $table)  
{  
    $result = $mysqli->query('SELECT * FROM '.$table);  
    $num_fields = $result->field_count;  
 
    $return .= 'DROP TABLE IF EXISTS '.$table.';';  
    $row2 = $mysqli->query('SHOW CREATE TABLE '.$table)->fetch_row();  
    $return .= "

".$row2[1].";

";  
 
    for($i = 0; $i < $num_fields; $i++)  
    {  
        while($row = $result->fetch_row())  
        {  
            $return .= 'INSERT INTO '.$table.' VALUES(';  
            for($j=0; $j<$num_fields; $j++)  
            {  
                $row[$j] = addslashes($row[$j]);  
                $row[$j] = str_replace("
","\n",$row[$j]);  
                if (isset($row[$j])) { $return .= '"'.$row[$j].'"' ; } else { $return .= '""'; }  
                if ($j<($num_fields-1)) { $return.= ','; }  
            }  
            $return .= ");
";  
        }  
    }  
    $return .= "


";  
}

$backup_file = './backup/'.DB_NAME.'_'.date("Y-M-d").'_'.time().'.sql';  
$fh = fopen($backup_file, 'w');  
fwrite($fh, $return);  
fclose($fh);  

crontab -e

0 0 * * * /usr/bin/php /path/to/backup.php >> /path/to/backup.log